FCC : WAKE UP RADIO INTRA (WuR) – BODY NETWORK – IEEE

GENACHOWSKI REMARKS ON UNLEASHING SPECTRUM FOR MEDICAL BODY AREA NETWORKS – F.C.C. 2012 Posted : May 17, 2012

https://old.bitchute.com/video/BDBfzSLl4Huq/

WAKE UP RADIO INTRA – BODY NETWORK – IEEE

https://old.bitchute.com/video/kJEG1qmUDiW0/

https://pmc.ncbi.nlm.nih.gov/articles/PMC6983094/

2019 Dec 21;20(1):66. doi: 10.3390/s20010066

IEEE 802.11-Enabled Wake-Up Radio: Use Cases and Applications

Elena Lopez-Aguilera ^1,^*, Ilker Demirkol ², Eduard Garcia-Villegas ¹, Josep Paradells ¹

PMCID: PMC6983094 PMID: 31877691

Abstract

IEEE 802.11 is one of the most commonly used radio access technologies, being present in almost all handheld devices with networking capabilities. However, its energy-hungry communication modes are a challenge for the increased battery lifetime of such devices and are an obstacle for its use in battery-constrained devices such as the ones defined by many Internet of Things applications. Wake-up Radio (WuR) systems have appeared as a solution for increasing the energy efficiency of communication technologies by employing a secondary low-power radio interface, which is always in the active state and switches the primary transceiver (used for main data communication) from the energy-saving to the active operation mode. The high market penetration of IEEE 802.11 technology, together with the benefits that WuR systems can bring to this widespread technology, motivates this article’s focus on IEEE 802.11-based WuR solutions. More specifically, we elaborate on the feasibility of such IEEE 802.11-based WuR solutions, and introduce the latest standardization efforts in this IEEE 802.11-based WuR domain, IEEE 802.11ba, which is a forthcoming IEEE 802.11 amendment, discussing its main features and potential use cases. As a use case consisting of green Wi-Fi application, we provide a proof-of-concept smart plug system implemented by a WuR that is activated remotely using IEEE 802.11 devices, evaluate its monetary and energy savings, and compare it with commercially available smart plug solutions. Finally, we discuss novel applications beyond the wake-up functionality that IEEE 802.11-enabled WuR devices can offer using a secondary radio, as well as applications that have not yet been considered by IEEE 802.11ba. As a result, we argue that the IEEE 802.11-based WuR solution will support a wide range of devices and deployments, for both low-rate and low-power communications, as well as high-rate transmissions.

Keywords: wake-up radio, IEEE 802.11, IEEE 802.11ba, internet of things, green networks

1. Introduction

IEEE 802.11 (Wi-Fi)-based Wireless Local Area Networks (WLAN), with more than 9.5 billion devices currently in use around the world, have experienced significant growth in the last decade. Widespread IEEE 802.11 is the preferred radio access technology for indoor wireless communications with the highest market penetration, being present in almost all consumer electronics devices with network capabilities (smartphones, tablets, notebooks, etc.). However, IEEE 802.11 technology has not yet been considered for building either home automation solutions or wireless sensor networks due to the high price of the chips and their high power consumption. Nevertheless, with mass production the price gap is disappearing, e.g., IEEE 802.11 Espressif chip ESP8266 costs $1, which is cheaper than IEEE 802.15.4 or Bluetooth Low Energy (BLE) solutions. On the other hand, IEEE 802.11 has been used in devices that are powered by the mains supply or by batteries recharged quite frequently, and power consumption still remains a concern for standby, transmission, and reception modes. For example, Espressif chip ESP32 [1] (evolved ESP8266) requires 190 mA when transmitting at 54 Mbps with a power of 16 dBm. Another challenge is the infeasibility of a small size battery to provide the required peak current, although this limitation can be overcome with the use of supercapacitors allowing the storage of necessary energy to cover power peaks. Nevertheless, the main issue for IEEE 802.11 solutions appears in reception, with a current consumption of 95–100 mA, being the reception instant unknown in advance and thus requiring longer time for the reception process. The receiver has to be continuously in the active state, as transmission can occur at any time, or it can enter the active state periodically if a duty cycle is defined. The last option has been the solution commonly adopted for battery powered devices, but at the cost of introducing delay in the transmission, synchronization overhead, and energy waste due to idle listening and the use of low-precision clocks. Moreover, considering only power peak is not fair when comparing IEEE 802.11 and IEEE 802.15.4 technologies. If we consider the energy per frame in transmission and in reception modes, IEEE 802.11 offers clear advantages over IEEE 802.15.4. One of the most power efficient IEEE 802.15.4 chips, TI CC2630 [2], consumes 73 μJ (with a power of 0 dBm) for the transmission of a 125 byte frame, and 70.8 μJ for its reception. For the IEEE 802.11 ESP32 chip, the energy per such frame is 10.55 μJ in transmission (with a power of 16 dBm and 54 Mbps) and 5.5 μJ in reception, thus, IEEE 802.11 offers an energy saving of one order of magnitude with respect to IEEE 802.15.4, and thereby is better suited for devices with a limited source of energy.

On the other hand, it is expected that the number of sensor nodes (devices able to collect sensory information and to communicate within a network) with non-cellular connections will exceed the number of consumer electronics devices in the near future, and that such sensor nodes will account for more than half of the Internet of Things (IoT) devices. With these devices being powered by batteries or energy harvesting, it is of key importance to use low-power equipment and further reduce energy consumption. For this reason, different initiatives are currently being developed within the IEEE 802.11 Work Group (WG) to link aforementioned two paradigms; one example is the IEEE 802.11ah standard, intended to define low-power and long-range WLAN communications, and a further step is expected from the IEEE 802.11 task group TGba, currently working on a Wake-up Radio (WuR) standard for IEEE 802.11 WLAN.

Compared to the duty cycle solutions, where the receiver goes to a sleep state and wakes up periodically for the defined duty cycle, WuR systems achieve higher energy efficiency by employing two transceivers at the receiver: A primary transceiver for main data communication and a secondary receiver used to switch the primary transceiver from an energy-saving state to active operation (Figure 1). This secondary receiver, called the WuR receiver (WuRx), has very low-power consumption and, therefore, can be permanently active without a significant sacrifice in terms of battery life. The WuRx wakes up the primary radio upon reception of a WuR call (WuC) signal from a WuR transmitter (WuTx). Moreover, in addition to the energy saving use case, WuR solutions can be used for synchronization, or for notifying a device about a relevant event, thus alerting a receiver about the next transmission. Thus, due to the aforementioned reasons, the IEEE 802.11 TGba (working on the forthcoming IEEE 802.11ba specification) is focused on the WuR standardization employing IEEE 802.11 technology. The WuR solution to be adopted by TGba would result in a single integrated solution for both low-rate and efficient low-power communications, but also for high-rate traffic transmissions, thus making this specification applicable in a wide range of devices and deployments.

In this article, we study the feasibility and advantages of IEEE 802.11-based WuR solutions, which are built on widely adopted IEEE 802.11 technology, thus exploiting the benefits of WuR systems to achieve energy efficient communication. More specifically, we review the existing WuR systems, focusing on IEEE 802.11-based WuR solutions (Section 2), and show the forthcoming IEEE 802.11ba amendment, discussing potential cases of its use (Section 3). For the use case of a green Wi-Fi application, we show the feasibility of such WuR solutions through a proof-of-concept (PoC) smart plug implementation of an IEEE 802.11-based WuR using off-the-shelf devices, evaluating its monetary and energy savings, and comparing it with commercially available solutions (Section 4). Finally, potential future applications of IEEE 802.11-based WuR solutions are depicted, whilst also showing that a Wi-Fi WuR receiver can be used for novel purposes beyond the wake-up functionality, and thus, beyond the TGba focus (Section 5). Following this discussion, the article is concluded in Section 6.

2. Wake-Up Radio Systems So Far

In this section we provide a thorough review of the state of the art on WuR systems.

Most wake-up communication solutions focus on the use of radio frequency (RF) signals [3], although there are solutions built on acoustic [4] and Infra Red (IR) [5] technologies. WuR can be classified as active or passive based on whether they require an attached power source, addressable or non-addressable based on whether a specific node or group of nodes can be specified in the WuC, and configurable or non-configurable based on whether the WuRx settings can be modified, e.g., its address or the communication settings.

To reduce the power requirement of WuRx, a trivial approach is to simplify its circuit design. The first proof-of-concept for WuRx in the literature, in fact, only features a capacitor and a rectifying diode [6]. Albeit being non-configurable, this low-complexity solution is addressable, for which the WuTx transmits signals at specific frequencies simultaneously to activate an intended WuRx. Yet, this WuR system reaches a very limited operational range of only a few meters. A common method to achieve low-power WuRx is the use of envelope detection techniques to eliminate the power hungry local oscillators used in conventional radios. However, this creates a challenge for the development of high frequency WuRx and, hence, for high rate and low delay solutions.

Another common approach for efficient WuRx design is the use of hardware correlators. In that approach, a shift register stores the address demodulated from a WuC by an analog to digital conversion (mostly performed by envelope detectors). At each clock cycle, the register bits are shifted by adding the newly received bit. Then, the correlator circuit correlates the received bits to a pre-stored array of bits corresponding to a preamble and/or WuRx address. In case of a match, the wake-up interrupt is generated (the wake-up pin is asserted). Correlator circuits can consume only few μA when in idle state and around 10 μA when fully active and decoding the WuC address [7]. Hence, all correlator-based WuRx designs implicitly feature addressing capabilities. The addressable WuRx proposed in [8] is one of the lowest power solutions in the literature, consuming a mere 4.5 nW. To achieve such low power with an impressive −63.8 dBm sensitivity, its design also uses the envelope detector and correlator approach.

IEEE 802.11-Based WuR Solutions

More specifically, there have been several studies focusing on the implementation of IEEE 802.11-based WuR systems in the literature. First, in [9], legacy IEEE 802.11 Beacon frames are used for generating a WuC. Upon energy detection over a threshold, the WuRx wakes up the main radio. IEEE 802.11 legacy transmitters can be used to generate the WuC, however, the system shows an important drawback, as the number of false positive detections is high, due to noise and interfering signals. Thus, the same authors incorporate in [10] an address pattern, in order to overcome this issue. This proposal alternates the transmission of long IEEE 802.11 legacy data frames and silence periods, to generate on and off periods respectively, and to code address patterns in a Non-Return-to-Zero (NRZ) manner. Nevertheless, the long silent periods make this proposal still prone to interference. In [11], a WuR is proposed where the legacy IEEE 802.11 frame lengths are used for address coding. In addition, this proposal provides various mechanisms to reduce the number of false positive detection and, thus, is more resilient to interference. Nevertheless, the consumption of the WuRx design is in the mW order, which is too high for a WuRx. On the other hand, following a different approach, in [12] a WuR system is proposed with the transmission of modified IEEE 802.11 Orthogonal Frequency Division Multiplexing (OFDM) symbols to build the WuC and address identifiers. The subcarriers that compose the OFDM signal are grouped in different sets, forcing some of them to zero, and building in this sense the address pattern in the frequency domain. This proposal has only been validated through simulation and its implementation of the WuC by employing legacy IEEE 802.11 transmitters is infeasible. In [13], a WuR system is presented by building the WuC by controlling the data pattern of OFDM subcarriers and producing an amplitude modulated signal composed of subsequent OFDM symbols. The IEEE 802.11ah OFDM symbol duration has been used for this purpose. Unfortunately, the complete system block diagram of IEEE 802.11 transmitters has not been taken into account, thus resulting in the system not being implementable by legacy IEEE 802.11 equipment. In [14], a WuR system is presented with the WuC being generated through a single IEEE 802.11 frame. It is modulated with an amplitude-based digital modulation employing the properties of the OFDM PHY. However, this proposal only provides evaluation through simulation. In [15], a WuR system solution is proposed, where the WuC consists in On-Off Keying (OOK) modulated data incorporated into a single IEEE 802.11 frame, and with a WuRx consumption of 95 μW. Although the complete system implementation is presented, legacy IEEE 802.11 transmitters need a firmware update for WuC development. In [16] we presented a WuR system comprising of a low-power receiver (10 μW). Unlike in previous references, the transmitter can be implemented on any IEEE 802.11-enabled device without requiring any firmware or hardware modification, including smartphones. The WuC is modulated using OOK, where on periods are generated by the transmission of subsequent legacy IEEE 802.11 broadcast frames of minimum length, and off periods are achieved by means of a silence period. After significant scientific community interest in this topic, standardization efforts were started within IEEE. Specifically, IEEE 802.11 WG initiated the task group TGba in December 2016, aiming at developing a new IEEE 802.11 amendment for WuR operation [17,18]. In Section 3 we present the forthcoming IEEE 802.11ba amendment.

3. IEEE 802.11ba Amendment

Since December 2016, IEEE 802.11 WG TGba has worked on the IEEE 802.11 amendment development for WuR operation, i.e., the latest standardization effort in the IEEE 802.11-based WuR domain. Earlier, in July 2015, a new Topic Interest Group (TIG) on Long-Range Low-Power (LRLP) operation for IoT was started, which aimed to bring some of the new IEEE 802.11ah features (targeting 868/915 MHz bands) to the 2.4 GHz band while keeping compatibility with mainstream IEEE 802.11 devices in that band. In May 2016, the TIG agreed to focus on the low-power feature (leaving aside the long range topic), thus creating the Low-Power WuR Study Group (LP-WuR SG), and dissolving the LRLP TIG. From May to November 2016 LP-WuR SG worked to meet the requirements needed to become a task group within the IEEE 802.11 WG, in charge of producing the new IEEE 802.11ba amendment. The new task group TGba, approved in December 2016, is currently working on the draft document, defining PHY and MAC layer specifications to enable the operation of a WuR system [17].

3.1. Usage Models

In order to foresee the requirements that future IEEE 802.11ba technology is expected to meet, engineers try to imagine different scenarios where the use of IEEE 802.11-based WuR will bring evident benefits. In this way, TGba first defined its target usage models [19]. The challenges identified in these usage models are then translated into functional requirements to guarantee that the resulting specification makes the new technology capable of enabling them. Most usage models discussed within the TGba are built on the following basic operation: (i) The primary radio (and possibly other energy-hungry systems) of an IEEE 802.11ba-capable low-power device is put to sleep in order to save energy; (ii) when communication with the sleeping device is required, a WuR packet (WuP) is sent in order to generate the WuC to wake up the device’s primary radio; and (iii) normal IEEE 802.11 communication happens through the primary radio (Figure 2). This basic operation poses three requirements that are common to all studied cases. First, since primary radios are responsible for sending WuPs, coexistence of these new frames with legacy IEEE 802.11 transmissions must be enabled. Second, the range of WuR communication should be the same as the one of the primary radio so that normal IEEE 802.11 operation is possible after the wake-up. Third, WuR-capable devices must be uniquely identified so that the WuP has effect only on the intended recipient. However, some of the studied usage models will require additional functionalities, as discussed below.

IEEE 802.11ba usage case basic operation.

Smart home: A domestic environment, where one access point (AP) serves stations (STA) without power limitations (e.g., TV, PC, household appliances) sharing space with tens of low-power battery-driven sensors/actuators of smart home applications (e.g., smart-metering, assisted-living, security/safety, home automation). In this scenario, WuP transmission copes with intensive use of the Wi-Fi channel (e.g., due to video streaming, gaming).

Warehouse: A large indoor space served by multiple APs. Each container/box or each shelf is equipped with sensors that report, on-demand, the location or state of the stored goods to a central server or to the warehouse workers’ handheld devices. In this scenario, each AP should support several hundreds of IEEE 802.11ba-capable devices.

Cattle farm: Outdoor scenarios in which the livestock carries different sensors. The farmers are equipped with mobile phones which work as APs serving the mobile sensors. Farmers use the phones to track the state (e.g., body temperature, location) of each animal independently. Upon request, those mobile phones will wake up the device mounted on the animal before querying its state through the main radio. However, mobile phones will also benefit from energy savings; thus, this scenario introduces the possibility that an AP is equipped with a WuRx so that it can switch to sleep mode while allowing the delivery of event-triggered reports from the sensors to the sleeping AP through an AP-destined WuP.

Wearable devices: In this scenario, personal or body area networks in fitness/health applications are built by connecting different wearable devices (e.g., smartwatch, chest strap) to a smartphone via Wi-Fi. Similar to the cattle farm case, this scenario also considers bi-directional WuP transmission whereby the phone could poll periodically different wearable devices and, in the opposite direction, a heart-rate sensor, for example, wakes up the smartphone to trigger an automatic emergency call upon detection of a heart failure.

Moving goods: Freighted containers or parcels, equipped with IEEE 802.11ba-capable sensors, are located and tracked from a central server. While in motion or upon arrival to a transfer station/warehouse, local APs wake up those sensors to record their current location. Note that, in this case, a unique identifier within the scope of the AP is not enough as the identifier must be unique in a more global context.

Intelligent Transportation System (ITS): Vulnerable road users (e.g., pedestrians or cyclists) need power-efficient communication devices in order to facilitate its integration within an ITS. In an example of such an application, when a pedestrian approaches a dangerous intersection or moving vehicle, the infrastructure or the vehicle itself sends WuP so that the pedestrian-carried device turns on automotive safety radio operation. This case requires support for multicast/broadcast transmission and operation outside the context of the Basic Service Set (as defined in IEEE 802.11p [20]).

3.2. PHY and MAC Characteristics

In the PHY layer being specified by the TGba, the 20 MHz non-High Throughput (non-HT) preamble will be used for any WuR PHY Protocol Data Unit (PPDU), immediately followed by a 20 MHz OFDM symbol with Binary Phase Shift Keying (BPSK) modulation of 4 μs duration, the Synchronization (SYNC), and the Data fields (Figure 3). The employment of non-HT preamble allows WuR frame transmissions to be sensed by any legacy IEEE 802.11a/g/n/ac station, building the 20 MHz non-HT preamble and the BPSK OFDM symbol together with the 20 MHz WuR PPDU preamble. On the other hand, SYNC and Data fields consist in the narrowband portion of the WuR PPDU, as the number of OFDM subcarriers employed is reduced to 13 subcarriers spaced 312.5 kHz each, i.e., SYNC and Data fields occupy 4 MHz of bandwidth instead of 20 MHz, thus leading to a simplified lower power receiver while still maintaining a suitable Signal to Interference and Noise Ratio (SINR). The aforementioned described PPDU is referred to as WuR PPDU with a 20 MHz channel bandwidth.

IEEE 802.11ba WuR 20 MHz PPDU (PHY Protocol Data Unit).

Only two rates are supported to achieve a simplified receiver: A high rate of 250 kbps (assuming a 1 bit per legacy IEEE 802.11 symbol of 4 μs), and a low rate of 62.5 kbps (as a more robust communication mode for noisier environments). SYNC field consists of being in the narrowband preamble dealing with synchronization, frame detection, and rate indication functionalities. Two different SYNC durations (64 μs or 128 μs) are employed depending on the bit rate used in the Data field (the high-rate of 250 kbps or the low-rate of 62.5 kbps, respectively), with SYNC field bit sequences being chosen for a reduced Frame Error Rate (FER). Moreover, Multi-Carrier (MC)-OOK modulation with Manchester coding is being employed for the Data field symbols, which provides on and off periods for both one and zero bit values, thus avoiding continuous large off periods leading to false idle medium detection by surrounding stations. Symbol’s duration depends on the bit rate, and its structure on whether a one or a zero bit value is being transmitted. In this way, for 62.5 kbps, a 16 μs long symbol is employed, with four differentiated sub-parts of 4 μs each alternating on and off periods, following a different schedule for transmissions of one and zero bits (Figure 4a). On the other hand, for 250 kbps, symbol duration is 4 μs with two sub-parts of 2 μs each, also alternating the on and off periods differently for transmissions of one and zero bits (Figure 4b).

IEEE 802.11ba WuR symbol structure: (a) Data symbol for 62.5 kbps, (b) Data symbol for 250 kbps.

TGba PHY provides optional support for 40 MHz and 80 MHz channel bandwidth. In this case, WuR PPDUs with 40 MHz and 80 MHz channel bandwidth, respectively, are transmitted using Frequency Division Multiple Access (FDMA), where the 20 MHz WuR PPDU preamble is duplicated in each 20 MHz sub-channel, thus allowing WuR frames transmissions to be sensed by any IEEE 802.11n/ac station in both primary and secondary channels. Subsequently, the 4 MHz WuR signal centered in the 20 MHz sub-channel is transmitted. Moreover, transmissions in separated sub-channels can use different bit rates (the high-rate of 250 kbps or the low-rate of 62.5 kbps), thus, different SYNC field sequences (with corresponding distinct duration) and data field durations may be applied. As the WuR PPDU in each 20 MHz sub-channel needs to have an equal duration of transmission, the padding may be used to ensure this condition (Figure 5).

IEEE 802.11ba 40 MHz and 80 MHz WuR PPDU: (a) 40 MHz WuR PPDU, (b) 80 MHz WuR PPDU.

The MAC layer defines the WuR mode to where stations are allowed to enter after WuR mode negotiation and explicit signaling. Stations in the WuR mode have their primary radio in sleep state and the secondary radio actively listening for WuP. Once the WuP is received, the station changes the state of the primary radio from sleep to awake, replies to the sender, and can turn off the secondary radio. Additionally, stations may support a duty cycle mode for WuR mode operation, with active and inactive periods also in the secondary radio, thus allowing higher power savings. Enhanced Distributed Channel Access (EDCA) with any of its four access categories is used as a channel access mechanism to send WuP, thus allowing coexistence with legacy IEEE 802.11 frames. Unlike legacy MAC, if transmission fails, it is retried without increasing the contention window value, which avoids additional delays in the WuP transmission, and thus in WuR operation.

The MAC frame structure of WuR frames is depicted in Figure 6 and contains a simplified MAC header field (composed by Frame Control, ID, and Type Dependent (TD) Control fields), an optional frame body of variable length and a Frame Checksum Field (FCS), as for legacy IEEE 802.11 frames. The Frame Control field inside the MAC header identifies the type of frame (as for legacy IEEE 802.11 frames), but limiting the frame types to Beacon, WuP, Discovery (to assist stations in WuR mode for WuR AP discovery through selected discovery channel scanning), and Vendor Specific frames. The ID field included in the MAC header does not correspond to the MAC address as in IEEE 802.11 legacy frames, but to an identifier that depends on the type of WuR frame. Thus, it can either identify the transmitting AP, or an individual station or a group of stations to which the WuR frame is addressed. The TD Control field contains information based on the specific WuR frame type.

4. A Proof-Of-Concept IEEE 802.11-Based WuR Implementation

In this section, we illustrate how IEEE 802.11 can be used to develop a WuR system and provide a real use case consisting of a green Wi-Fi application that is built on this IEEE 802.11-based WuR solution. For this, we first detail the WuR system, the preliminary version of which was presented in [16]. This WuR system consists of a low-power WuRx and a WuTx that can be implemented on any IEEE 802.11-enabled device, without any firmware or hardware modification. It provides a PoC IEEE 802.11-based WuR implementation using IEEE 802.11 off-the-shelf devices, as detailed in this section. It also allows us to show the energy and monetary cost savings that can be offered by an IEEE 802.11-enabled WuR system in this exemplary green Wi-Fi application. In this use case, Wi-Fi APs are moved to a power saving state when not in use, and woken up by a Wi-Fi STA upon request.

4.1. IEEE 802.11 as WuR Technology

The system consists of a standard IEEE 802.11-capable device, which has the role of the WuTx, and a low-power WuRx. The WuRx, as depicted in Figure 7, is built by preceding the AS3933 [21] integrated circuit, with a 2.4 GHz antenna and the corresponding impedance matching stage. The AS3933 WuRx chip features a kHz-level high-performance envelope detector and an address correlator. The signal received is down-converted from the GHz to the kHz level, after impedance matching, by employing an envelope detector (ED) and a Low-Pass Filter (LPF). One inductance and two capacitors build the L-network that matches the 50 Ω output impedance of the antenna to the input impedance of the Schottky diode. Next, the AS3933 extracts the node address modulated in the WuP using an internal envelope detector. The data slicer block included in the AS3933 allows data delimitation according to the bit rate of the WuR system. An Interrupt ReQuest signal is generated to wake up the device from its sleep mode, upon detection of the device’s pre-configured address by the address correlator block in the AS3933.

Proposed IEEE 802.11 WuRx (WuR receiver) implementation.

The WuRx presented listens for a kHz-level signal modulated in the 2.4 GHz band according to an OOK modulation. The proposed system follows the so-called SubCarrier Modulation (SCM) procedure [7], which is shown in Figure 8. It combines the transmission of a regular IEEE 802.11 frame bursts (ones) and silence periods (zeroes) to emulate a 16 kHz carrier. It is employed to OOK-modulate the WuP, which contains a preamble and an address field. Broadcast empty data frames are used for the transmission of regular bursts of standard IEEE 802.11 frames, since they do not require an acknowledged two-way exchange and can be sent with a minimum separation of a DCF inter-frame space (DIFS) time. Any device equipped with a Wi-Fi compatible device can generate this kind of signal only with software modifications. For this PoC, we use a desktop PC running Linux with a Qualcomm-Atheros IEEE 802.11g card supported by the open source MadWifi driver. We programmed a simple user-level application to generate the frame bursts (i.e., the emulated low-rate OOK signal for WuP generation). For a single wake-up event, a total wake-up latency of 45.87 ms was measured. We refer the reader to reference [16] for a detailed evaluation.

WuP (WuR packet) in proposed WuR implementation.

In our implementation, the WuRx featured a sensitivity of −52 dBm. Following the approach in [22], a led on the WuRx board was turned on by the MCU upon WuP reception, being the minimum power level measured to −52 dBm, while still correctly detecting the WuP. This sensitivity was translated into an effective range of near 40 m (in highly interfered outdoor scenario) when the wireless card was transmitting at +18 dBm with +2 dB of antenna gain. This analysis has been done experimentally in an outdoor highly interfered campus environment and in an interference-free indoor scenario using a test setup with WuTx and WuRx placed at a height of 1 m. The WuTx transmits 10 WuPs per second (up to a maximum of 100 WuPs), and the WuRx is progressively displaced away from the WuTx in steps of 2 m. Each measurement is averaged over 5 repetitions. No WuP is detected beyond 40 m [16]. Average delays of 2.3 s for the outdoor scenario have been measured, which are acceptable values for many applications, thus showing the robustness of the system in highly interfered scenarios. To compare this range with the theoretical limits, we simulate two well-known propagation models and depict the results in Figure 9. As seen in the figure, the operational range for the 2-ray Ground Reflection and Friis Free Space propagation models for the given sensitivity is 20 m and 35 m longer, respectively, than that of our WuRx prototype. Such deviations are reasonable due to the losses in the hardware implementation. The WuRx achieves a measured, remarkably low power consumption of 10.8 μW in sleep mode and of 24 μW during WuP reception and decoding [16]. These values include the power required by the AS3933 and the low-power MCU TI MSP430F2350 [23], which has been used in the WuRx board. This MCU requires 0.3 μW in its lowest power mode LPM4. This means a battery lifetime of between 3 and 7 years, depending on WuP arrival frequency and considering a common CR2032 battery with 225 mAh of capacity.

Operational ranges corresponding to the two theoretical propagation models for the WuRx sensitivity measured of −52 dBm. The red dot shows the maximum distance observed in the experimental measurements.

4.2. Proof-Of-Concept: Wi-Fi Controlled Smart Plug

By using the IEEE 802.11-based WuR system described in the previous section, we developed a smart plug, which deals with green Wi-Fi AP operation and can be controlled by any off-the-shelf IEEE 802.11 device. Two versions of the switch were designed: (i) The smart plug is powered directly from the mains voltage, for example by simply plugging it to a wall-mount plug; and (ii) A smart DC switch, which uses a DC voltage input, to be used, for example, between the power adapter and the electronic device.

The first case (AC solution) can be considered as a universal plug solution since it will allow the connection of many of the most common appliances, supporting a higher switching voltage/current than the DC option. However, the AC solution still requires an AC/DC conversion to feed the WuRx (3.3 V) and requires components that are slightly more expensive. The DC solution is powered with 12 V provided by the power adapter of the electronic device (i.e., the Wi-Fi access point in this case). Then, it is suitable for the specific case of the selected access point but also for all the DC devices that are in the electrical ranges of the designed components. The design of both approaches face different trade-offs, for example the choice of a mechanical relay or a solid-state relay. The latter has a longer life and switches faster while the mechanical relay (latching type), on the other hand, shows a peak of consumption only during switching time but wastes exactly 0 W during on and off periods, while solid-state counterparts cannot provide a perfectly open circuit and present small current leakage both in the on and off state.

The architectural design of our smart plug is given in Figure 10. The current measurement circuit is used to differentiate between the operational and the standby modes by comparing the actual current consumption to a reference value. This allows the plug to detect periods of low or no activity and automatically switch off the connected device. Although, for this study, we provided a fixed threshold (if measured current is below the threshold, state changes to off), and more generic solutions can be devised, for example, by registering the standby and active modes of an electronic device through user interaction. A 3.3 V power converter has also been designed with a non-isolated capacitive power supply to feed the WuRx.

In our PoC, we targeted a green Wi-Fi AP application, where an AP was turned off automatically if there was no station associated to it, and the same AP could be turned on remotely by a Wi-Fi STA by waking the smart plug up. For this, we used a commercial Wi-Fi AP, TP-Link WR1043ND, the power consumption of which was experimentally measured with a power analyzer (Agilent Technologies N6705A) in different states to configure the threshold for the current measurement circuit: (i) The AP is on and serving zero STA, (ii) the AP is on and serving one STA at least. It was found that, when the AP was on, the measured current consumed by the AP when serving zero or one STA was very similar (230 mA–250 mA vs. 230 mA–260 mA). This is expected since the AP is consuming a considerable power for listening the channel and responding to probe messages. In consequence, the current measurement circuit (cf. Figure 10) could not clearly distinguish the cases where the AP could be switched off to save energy (i.e., no STAs associated). In this case, some kind of action is needed from the AP to trigger a transition to the off state. Hence, we programmed the AP, running a Linux-based operating system, to execute the poweroff command, whenever there was no STA associated. When this command was executed, the measured current consumption was lowered to 160 mA–170 mA range, which allowed us to set a clear threshold to identify power saving opportunities.

After comparing the performance of different electrical components and their influence on the performance of the final solution (i.e., measuring their contribution to the energy consumption in on and off states of the switch), as well as their price, we developed two versions of the smart plug, namely DC and AC solutions, as discussed above. In both cases, we used low-cost off-the-shelf components, resulting in a device with an estimated cost between $7 and $10.

A first set of experiments were conducted to validate the correct operation of the WuRx shown in [16], that is, measure range, delay, and power consumed by the Wi-Fi WuRx element (see Figure 10). Then we experimentally quantified the power saving that could be achieved with this solution by measuring the power consumption in different states. In the operational state of the AP, the total measured power consumption was 4 W without the smart plug solution, but was increased to 4.3 W and 4.5 W with the DC and AC smart plug solutions, respectively. However, when there were no STAs associated, the AP was automatically turned off, as discussed in the previous paragraphs, reducing the measured power consumption to 0.5 W (DC) and 1 W (AC). Hence, compared to the most common scenario where APs remain always active regardless of their utilization, WuR-controlled AP solution reduced the power consumption by 87.5% (DC) and 75% (AC).

In the common use case of office WLANs, our developed WuR PoC solution allows the APs to be put to this energy saving mode most of the time, e.g., between 18:00 and 08:00. In a campus scenario, this mechanism translates to savings of around $6500 per year for an Extended Service Set (ESS) of 2000 APs, corresponding to the utilization of the WLAN measured in a large university campus [24]. Table 1 summarizes the performance of the two smart plug solutions, as well as the energy and monetary savings achieved in different scenarios.

Table 1.

Smart plug performance (P. cons.: Power consumption, P. sav: Power saving).

	Offices Building	University Campus	Household
Active hours	08:00–18:00	08:00–22:00	18:00–00:00
Number of APs	100	2000	1
P. cons. w/o plug	(4 W × 24 h × 100)	(4 W × 24 h × 2000)	(4 W × 24 h × 1)
P. cons. w/ DC sol.	(4.3 W × 10 h + 0.5 W × 14 h) × 100	(4.3 W × 14 h + 0.5 W × 10 h) × 2000	(4.3 W × 6 h + 0.5 Wx18 h) × 1
P. sav. w/ DC sol.	1679 kWh × year	22484 kWh × year	22.3 kWh × year
P. cons. w/ AC sol.	(4.5 W × 10 h + 1.0 W × 14 h) × 100	(4.5 W × 14 h + 1.0 W × 10 h) x 2000	(4.5 W × 6 h + 1.0 W × 18 h) × 1
P. sav. w/ AC sol.	1350 kWh × year	16790 kWh × year	18.6 kWh × year
Price of electricity	$0.29 kWh	$0.29 kWh	$0.29 kWh
$ saving w/ DC sol.	$487 × year	$6520 × year	$6.5 × year
$ saving w/ AC sol.	$392 × year	$4869 × year	$5.4 × year

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The numbers shown in Table 1 correspond to the savings achieved when the smart plug is used with the lightweight TP-Link WR1043ND Wi-Fi AP. However, the developed smart plug solution supports appliances of up to 4 kW. For appliances that require such high power, this smart plug solution can achieve even more significant savings.

There are commercial smart plug solutions employing Wi-Fi communication and other radio frequency technologies such as Bluetooth, Zigbee, or GSM. In this regard, the Wemo Smart switch from Belkin [25] employs Wi-Fi and supports up to 1.8 kW appliances with a maximum power consumption of 1.5 W. The iSocket smart switch [26] uses GSM, supports up to 4 kW, and consumes 1 W. Both solutions can be remotely controlled from a smartphone device. The Valta Starter Kit [27] works with the 921 MHz frequency band, supports up to 1.8 kW appliances, and consumes up to 1.1 W. The Loxone Smart Socket [28] operates within the 868 MHz band and allows up to 4 kW with a power consumption of 0.5 W. However, the last two devices cannot be controlled from a smartphone, requiring an additional hardware for monitoring and configuration, which brings the important drawback of additional power consumption. In comparison to aforementioned commercial devices, our developed smart plug solution can be remotely controlled by smartphones employing Wi-Fi, consumes less than 1 W, and can control appliances of up to 4 kW of power consumption, thus showing that it is aligned with commercial devices. In addition, it consists of, in the first solution, a current (power) threshold to turn off the appliance automatically. Moreover, power consumption can be further reduced by removing the current measurement circuit and replacing the AC/DC converter of Figure 10 by a battery, as our smart plug incorporates a WuR system that allows one to considerably reduce power consumption ( Section 4.1). Finally, our smart plug design provides a lower-cost solution since it does not require a fully functional IEEE 802.11 chipset nor a MCU running a complete TCP/IP stack.

5. Beyond Wake-Up Functionality

The presence of the secondary low-power radio interface in IEEE 802.11-based WuR solutions enables a wide range of new future applications beyond the wake-up functionality and the scope of TGba. Some of them are depicted in Figure 11 and are discussed below in this section.

Potential use cases for a WuRx radio beyond of wake-up functionality: (a) Sleep message to activate energy saving state, (b) WuP forwarding, (c) Out-of-band signaling between APs, (d) Communications between Wi-Fi and non-Wi-Fi devices.

Maybe the most obvious next step could be the use of a second type of packet other than the WuP, intended to switch battery-driven devices or the AP itself to an energy-saving state when required (e.g., out of office hours in an enterprise network), to achieve energy savings, reduced interference, or increased security (see Figure 11a). Another application not yet considered by TGba is WuP forwarding, which would allow the transmission of a WuP to devices out of the sender’s range, through a multi-hop path (see Figure 11b), where the range of WuR communication is not the same as the one of the primary radio.

The secondary radio could also be used to receive out-of-band signaling in a multi-AP environment, where neighboring APs operate in non-overlapping channels to avoid interference (see Figure 11c). In such scenarios, both APs and non-AP STAs often scan other channels to discover neighboring APs. With a secondary radio used for that purpose, those STAs’ primary radios will be able to keep operating in their home channel without any loss of connectivity. For that application, WuPs would include the initial configuration information such as channel number, bandwidth, Extended Service Set Identifier (ESSID), etc. In another exemplary embodiment of such functionality, APs could send other relevant signaling to neighboring APs without changing the frequency of the primary radio, for example, WuPs could include synchronization information when the intended receivers operate as anchors in time-measurement-based positioning (cf. IEEE 802.11az).

Moreover, IEEE 802.11ba implies the design of a low-power radio capable of receiving messages from IEEE 802.11-compatible devices, but this low-power radio could be mounted in any kind of device, which does not necessarily have an IEEE 802.11-based primary radio (see Figure 11d). This would enable communication between Wi-Fi devices and any non-Wi-Fi device. Nowadays, most (if not all) handheld devices with networking capabilities are equipped with an IEEE 802.11 interface. However, up until now and despite Wi-Fi HaLow (IEEE 802.11ah) [29], IEEE 802.11 has not shown a significant presence in the IoT market, where other technologies are well established (e.g., ZigBee/IEEE 802.15.4e, BLE, and different proprietary technologies). Therefore, it is critical to provide a means of communication between these two worlds: Personal communication devices and IoT. We believe TGba’s low power and cheap radio could be used for that matter. For example, a low-power sensor/actuator with a primary radio different from IEEE 802.11 could be equipped with an IEEE 802.11ba-like WuRx for wake-up purposes, but also to receive short messages or simple control information (e.g., for initial configuration, neighbor discovery, interference avoidance) from a Wi-Fi device. Furthermore, WuRx could be installed in appliances with no primary radio at all. In those cases, the WuRx would allow a unidirectional communication whereby a Wi-Fi device, acting as a remote control, can send simple commands to actuators (e.g., garage door opener, window blinds, thermostat). Then, (non-IEEE 802.11) recipients of the WuP react accordingly, not being required to provide any feedback to the sender.

6. Conclusions

In this article we analyzed the eligibility of using IEEE 802.11-based WuR solutions. First, we provided a review of WuR systems, and present the forthcoming IEEE 802.11ba amendment, which aimed at developing the new IEEE 802.11 specification for WuR standardization. We showed and discussed the potential use cases, and provided a proof-of-concept IEEE 802.11-based WuR implementation to illustrate the use case consisting in a green Wi-Fi application. A comparison with commercially available solutions was shown, including its monetary and energy savings. Thus, we presented a complete operative WuR system using IEEE 802.11 off-the-shelf devices portraying its feasibility and significant advantages. Finally, we highlighted the possibility of using the secondary radio interface of IEEE 802.11-enabled WuR devices for new applications beyond the wake-up functionality, thus depicting future applications not yet considered by IEEE 802.11ba.

Author Contributions

Conceptualization, visualization, writing and review were provided by E.L.-A., I.D., E.G.-V. and J.P.; Investigation was conducted by E.L.-A., I.D. and E.G.-V.; Supervision was carried out by J.P.; Project administration and final editing was provided by E.L.-A. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded in part by the ERDF and the Spanish Government through projects RYC-2013-13029, TEC2016-79988-P, AEI/FEDER, UE.

Conflicts of Interest

The authors declare no conflict of interest.

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ACTIONS

Wireless Body Area Network (WBAN): A Survey on Reliability, Fault Tolerance, and Technologies Coexistence

March 2017

MARWA SALAYMA, AHMED AL-DUBAI, and IMED ROMDHANI, Edinburgh Napier University YOUSSEF NASSER, American University of Beirut

Wireless Body Area Network (WBAN) has been a key element in e-health to monitor bodies. This technology enables new applications under the umbrella of different domains, including the medical field, the entertain- ment and ambient intelligence areas. This survey paper places substantial emphasis on the concept and key features of the WBAN technology. First, the WBAN concept is introduced and a review of key applications fa- cilitated by this networking technology is provided. The study then explores a wide variety of communication standards and methods deployed in this technology. Due to the sensitivity and criticality of the data carried and handled by WBAN, fault tolerance is a critical issue and widely discussed in this paper. Hence, this survey investigates thoroughly the reliability and fault tolerance paradigms suggested for WBANs. Open research and challenging issues pertaining to fault tolerance, coexistence and interference management and power consumption are also discussed along with some suggested trends in these aspects.

CCS Concepts: r Computer systems organization → Sensor networks; Reliability; Fault-tolerant network topologies; Sensors and actuators; r Hardware → Wireless devices; Wireless integrated network sensors; Fault tolerance; Sensors and actuators; Sensor devices and platforms; Analysis and design of emerging devices and systems

Additional Key Words and Phrases: Wireless body area networks, QoS, medical, channel access, fading, WBAN standards

ACM Reference Format:

Marwa Salayma, Ahmed Al-Dubai, Imed Romdhani, and Youssef Nasser. 2017. Wireless body area network (WBAN): A survey on reliability, fault tolerance, and technologies coexistence. ACM Comput. Surv. 50, 1, Article 3 (March 2017), 38 pages.
DOI: http://dx.doi.org/10.1145/3041956

https://www.researchgate.net/publication/292152547_Wireless_Body_Area_Network_WBAN_A_Survey_on_Reliability_Fault_Tolerance_and_Technologies_Coexistence

Wake Up, FCC: The Internet Protocol Transition Is Now

By Richard Bennett

American Enterprise Institute

April 03, 2014

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Key points in this Outlook:

American citizens are far ahead of government agencies and holdout populations such as the elderly in transitioning to new networking technologies.
Society will benefit most from a rapid transition from telephone to broadband networks, but the Federal Communications Commission’s (FCC’s) Internet Protocol (IP) Technology Transitions Order is obstructing the transition.
The FCC’s order should be substantially revised to, among other things, accelerate the adoption of IP technologies in the realms of public safety, defense, and aviation.

Some 45 years after design work started on the cellular network and the Internet, the Federal Communications Commission (FCC) issued an Internet Protocol (IP) Technology Transitions Order amounting to a reluctant invitation for trials on the decommissioning of the legacy telephone network. While the telephone network is no longer the centerpiece of telecommunications in the United States or around the world, the FCC is clearly anxious about turning it off, probably because the FCC and telephone network grew up together. This reluctance is apparent in the many obstacles the FCC’s transition order places in the way of the decommissioning trials. These barriers are, to some extent, effects of FCC Chairman Tom Wheeler’s Network Compact, a historical artifact of the US Department of Justice’s 1913 Kingsbury Commitment authorizing the Bell System (AT&T) monopoly in return for some sweeteners.

While it is worthwhile to ensure that no essential capabilities are abandoned in the transition from the telephone network to its replacement (pervasive broadband networks running IP), it is important for the FCC to approach this transition sensibly. Americans are far ahead of the FCC and other government agencies in migrating from the old networks to the new ones, and the gap is growing every day. Rather than slowing down the transition with arcane regulations that require both large and small network operators to maintain compatibility with obsolete systems, the FCC should focus its efforts on encouraging holdout populations—in the public and in the private sector—to adapt to contemporary reality. The social benefits of a more rapid transition are greater than those of a slow one.

Government users have been slowest to adapt to the new technologies, so the FCC needs to make government adoption of new networks a priority. The order is littered with status quo–preserving conditions tailored to the Federal Aviation Administration (FAA), US Department of Defense (DoD), and public safety. Rather than holding back the public’s use of advanced networks while waiting for the government to catch up, the FCC needs to accelerate progress in the government sector. It may not be practical to require full government adoption of IP networks in the first phase of transition trials, but it must be part of the overarching plan.

Government’s struggle with technology is nothing new, but as networking technologies become more powerful and vibrant, government seems to do worse. For example, FirstNet, the national wireless public safety network first recommended by the 9/11 Commission, is floundering because the multiple government stakeholders who must cooperate to make FirstNet a reality cannot agree on a plan.[1] Government’s inability to police itself harms the public interest; such failures should not be allowed to impede the public’s acceptance and use of new networking technologies. The FCC’s order needs to address government-induced transition problems directly and not simply by increasing the burden on the public and on private-sector firms.

Transition from the Telephone Network

The story of the transition from the telephone to the pervasive broadband Internet as the primary means of electronic communication is one of conflict. Americans eagerly explore the horizons that the new technologies offer: they are rapidly cutting the cord on traditional telephone service and buying smartphones and both mobile and fixed-location broadband services. But the FCC is letting us down; instead of facilitating this transition, it does little more than throw obstacles in its path.

The principal means by which the FCC stands in the way of progress is through its insistence that it has discovered a Network Compact consisting of “enduring values” embedded in the corpus of telecom law that magically pertain not just to the particular historical circumstances around the formation of America’s telephone network, but also to all future networks. Effectively, the FCC wants the terms of the Kingsbury Commitment to constrain the growth of the Internet, lest something bad happens. This posture necessarily prevents any number of good things from happening as well, or at least postpones them indefinitely.

For most of the 20th century, Americans communicated with each other instantaneously at a distance by the grace of the telephone network. This network was a technical marvel at its birth, but advances in technology have reduced it to the status of a quaint reminder of how we used to live.

“The expense of maintaining the old networks only delays the construction and use of new ones that are better in every dimension.”

The telephone network has been replaced by a multitude of options: the mobile network, wireline broadband networks, satellite services, and public Wi-Fi networks (mostly provided by private companies) that are often free to use. While the telephone network was a uniform system, the plethora of networks we use today are unified only by IP, a small piece of software code that lacks the ability to move a single bit of information without the help of one or more of the diverse groups of modern communication networks that make up the new IP ecosystem. The telephone call is now nothing more than an application mediated by the Internet, which itself is little more than the public face of the vibrant new IP ecosystem.

While Americans have largely abandoned “plain old telephone service (POTS),” regulators who have invested careers in learning, interpreting, and applying telecommunications law are reluctant to let it go. There are still some holdouts among the citizenry as well—chiefly older people who do not care to learn how to use new technologies they see as intimidating, unreliable, or expensive. Hidebound regulators and holdout citizens are the primary obstacles to the complete phase-out of the telephone network and the reallocation of its operational expense in more worthwhile alternatives.

Similarly, while many Americans embrace the new technologies, many government agencies are stuck on the legacy network. The FAA, for example, insists that it cannot function without time-divison multiplexing (TDM) data links, but this agency has only just admitted that its 20-year ban on personal electronic devices aboard airplanes never had a factual basis.[2] We cannot afford to impose a similar delay on the phase-out of the public switched telephone network (PSTN). To do so would be to retard innovation, squander public interest benefits, and waste money.

While the FCC is clearly doing its best to serve the “public interest,” it must do better. Preserving the technologies of the past has sentimental and bureaucratic appeal, but it is ultimately counterproductive to delay new technologies that are already broadly accepted and widely used. The expense of maintaining the old networks only delays the construction and use of new ones that are better in every dimension.

“Each of the historical networks did one thing and one thing only. IP changed this paradigm.”

The FCC’s approach to telecom regulation comes from the technology silos in the Communications Act of 1934, and the silos in turn reflect 150 years of history. When the telegraph network was built, it was the only game in town—the one and only network that allowed people to communicate nearly instantaneously from coast to coast. One company owned all the facilities needed to send telegrams from border to border, so it was easy to regulate; policymakers defined norms and it was up to the telegraph company to implement them. When the Bell System was formed, policymakers applied similar logic and repeated the process for radio, cable TV, and wireless telephony.

Each of the historical networks did one thing and one thing only; none of them needed an app store because each ran one and only one application. IP changed this paradigm. We no longer need to build a separate network for each application; we simply build networks to reach users in particular circumstances at various ranges of price and service and rely on a common piece of software code, IP, to unite them at a web of Internet exchange points. We have mobile networks that serve us while we are in motion; nomadic networks that serve us during temporary stays in restaurants, hotels, and conference rooms; and stationary networks that serve our television sets, desks, and appliances. Each kind of network serves a range of activities and each supports an overlapping set of applications, some traditional and some emerging. The word “telecom” now describes a shrinking sliver of a robust and burgeoning networking ecosystem, but in the past it described the whole enchilada.

Consequently, thinking about the public interest must return to its roots. The actual interests of the public are distinct from those of regulators, and the levers that effectuate policy in a world of multiple networks with substantially similar capabilities are different from those that applied in the monolithic scenario of the past.

Enduring Values or Expedient Compromises?

In its order authorizing IP transition trials, the FCC lists four principles that it deems “enduring values that have always informed communications law.” In a statement attached to the order, Chairman Wheeler expounds on the Network Compact as the unifying theme behind these “enduring values”:

At this critical juncture, let me be clear about a few things. One, we favor technological innovation. And, two, we affirm the enduring values of the Network Compact: universal service, public safety, competition and consumer protection.

Our challenge is to preserve the values that consumers and businesses have come to expect from their networks, while unleashing new waves of investment and innovation, which will deliver untold benefits for the American people.

Today’s order kickstarts this national dialogue.[3]

These are noble sentiments. The problem is that in practice, “enduring values” easily degenerates to “current regulations,” as the FCC’s order demands that the telephone network not be shut down, even on an experimental basis, unless the replacement network satisfies the full raft of existing telephone network features, functions, and regulations.

In other words, the order translates these seemingly lofty principles into a laundry list of terms and conditions, the effect of which is to complicate the transition to an almost ridiculous degree. The FCC defines 17 set conditions, which it defines as “. . . values-based conditions that any proposed experiment must satisfy.” The commission insists that every experiment “comply with the Commission’s existing rules” drafted for the telephone network for these set conditions. In short, the FCC’s four enduring values become 17 status quo–preserving regulatory demands. The enduring values and their corresponding conditions are detailed in the following section.

Public Safety. These conditions enable the public to easily contact first responders, and they ensure that networks function during emergencies (to the extent that is practical).

911/E911 and Next Generation 911 (NG911) Capabilities. In practice, this condition means traditional 911 location services because the presence of a NG911 public-safety answering point (PSAP) cannot be guaranteed in each study area. It does not ask what can be done to speed up the deployment of NG911.
Safeguards to Ensure Public Safety Functionality in Adverse Conditions. This open-ended goal requires the experimenter to convince the FCC that it can respond to any “public safety failure” by “immediately restoring its legacy service, fixing its IP-based service, or providing a comparable service.”[4] Of course, there is no guarantee that legacy systems will work in the face of any adverse conditions today; we know they often fail for days or weeks at a time following earthquakes and storms. In fact, this condition imposes a burden on next-generation networks that POTS has never had to carry.
Protect Essential Communications Services for Safety of Life and National Security. This condition requires the experimenter to convince the FCC that the experiment allows for “the continuation of TDM-based networks and services for critical Federal systems until it is proven that IP-based solutions can meet system requirements for the performance of safety of life and national security missions.”[5] The FCC does not say what this proof might include, or why federal systems are so far behind those used by the private sector. Perhaps the government needs a bit more time to adapt to the technology that citizens already rely on, but we need some assurance that a plan is in place for modernizing its operations.
Network Security. The FCC requires only “reasonable measures” to harden systems against security threats and suggests that applicants consult the National Institute of Standards and Technology Cybersecurity Framework and applicable best practices and recommendations from the Communications Security, Reliability and Interoperability Council for guidance. This is reasonable, but security is one of the more serious problems with IP networks generally, and this area probably deserves more focus.
Backup Power. The FCC believes “the PSTN has a reliability advantage over an IP fiber-based or wireless network because the TDM copper network carries an independent source of power that preserves service during emergencies when the electric power grid fails. . . . The Commission will need to understand a range of hypothetical use cases involving commercial power outages of varying duration, e.g., ranging from a few hours to several days or weeks.”[6] The legacy network supplies power from batteries in switching centers to handsets in customer premises. Batteries are widely owned, of course, so this issue is a red herring. Backup power simply shifts from telephone company offices to handsets in the systems we now use.
Outage Reporting. The FCC wants applicants to commit “to filing outage reports and PSAP notification consistent with the Part 4 rules that pertain to each legacy service being replaced during an experiment, regardless of the extent to which the rules would apply in the first instance to the type of IP-based service that replaces it.”[7] This is perfectly sensible.
Communications Assistance for Law Enforcement Act (CALEA) Capabilities. The FCC “expects that providers participating in any experiment involving the provision of service to customers will satisfy CALEA, their obligations under Titles 18 and 50, and similar State requirements.”[8] As with the other requirements, the commission fails to consider whether the purposes of CALEA can be satisfied in a way that is less burdensome to IP networks, effectively placing the entire burden of progress on the private sector.

Universal Access. This set of conditions ensures that all Americans have access to some sort of communications network.

Ensuring Access for Persons with Disabilities. The FCC demands that “providers should pay particular attention to access to 911 services by individuals with disabilities, the provision of [Telecommunications Relay Services], the transmission of remote closed captions, and the development, use of, and compatibility with assistive technologies.”[9] This is consistent with the tradition of imposing requirements on the network for all users that the network supports, but it ignores the role that the advanced applications IP networks support can play in the disability space. Skype and text messaging are fine tools for the deaf, for example.
Specific Populations. The FCC expects “service-based experiments to protect the interests of specific vulnerable populations such as the elderly, individuals with limited English proficiency (LEP), low-income populations, residents of Tribal lands, and others who likely will be affected by changes in communications technology in ways different from the general population.”[10] Language proficiency is a widespread social issue, so its nexus with language-neutral communications networks that permit communication by text, voice, and video is questionable.
Maintain Universal-Service Status Quo. The FCC requires that “experiments will not deviate from any existing universal service rules and policies, and that applicants will continue to be subject to rules and policies regarding both support and contribution obligations.”[11] As I discuss later, the implementation of universal service in the monopoly context was very different than it is today, but the FCC seems not to notice. Backing up to the Kingsbury Commitment, universal service was originally a government objective that was outsourced to the Bell System. It should be funded from the Treasury, not by economically disadvantaged urban residents through particular communications firms. There is an opportunity to make meaningful progress toward universal-service reform in the course of the transition—progress that we cannot afford to lose.
Preserve and Enhance Broadband Access. The order insists that “it will be important for the Commission to understand in detail any changes in the speed, latency, or jitter of the Internet access services offered in the experiment area, and any differences in the price or usage capacities associated with those offerings.”[12] The Internet relies on packet switching, a communications technology that eschews latency and jitter control in favor of capacity. This is problematic for voice and video applications, but it is not immediately apparent how the experimenters might improve the FCC’s understanding of packet switching in comparison to the TDM technology it replaces. The confusion of packet switching and TDM is at the heart of the net neutrality debate.

Competition. These conditions are meant to promote the provision of network services by multiple providers and technologies.

Wholesale Access. The FCC demands that experimenters “maintain a competitor’s access to an applicant’s network.”[13] Allowing competitors access to the dominant firm’s network is a condition that was added to the legacy network after the advent of digital telephony to create the appearance of competition, but it has never lived up to expectations. Open access is not appropriate in nonmonopoly scenarios. As Jeffrey Eisenach, Roslyn Layton, and many other analysts have shown, open-access mandates suppress investment.[14]
Intercarrier Compensation (ICC). The FCC insists that networks “will maintain the status quo ante in their experimental arenas in accordance with the Commission’s USF/ICC Transformation Order, which addresses ICC revenue flows, including the ICC applicable to VoIP-PSTN traffic and related subsidies.”[15] Readers should mark this condition well, as it signifies the point at which the FCC has jumped the shark. ICC is a means for subsidizing uneconomical rural networks, and the transition out of the legacy network’s monopoly status to the competitive market scenario cannot even begin to take place until ICC is replaced with the free market for the peering and interconnection that characterizes the Internet. The FCC needs to drop this requirement and—if it really believes that enriching the owners of rural telephone companies is in the public interest—replace it with an open and transparent system of subsidies.
Interconnection. The rules require applicants to “maintain the status quo for interconnection in any service-based experiment.”[16] This largely repeats the ICC requirement and is similarly inappropriate. The transition from TDM to IP is not simply a matter of one technology replacing another; it is a matter of one market structure replacing another.

Consumer Protection. This set of conditions addresses traditional notions of full disclosure, truth in billing, and protection against false advertising and deceptive trade practices.

Customer Privacy. The FCC’s insistence that applicant networks “maintain network users’ reasonable expectations of privacy, regardless of the technology used”[17] skirts the concerns that Americans have about snooping and spying. The commission needs to be a lot clearer on what expectations of privacy are actually reasonable in a world in which the National Security Agency and commercial firms store personal data and create personal dossiers for commercial purposes and the limits of their missions. As the DC Circuit has observed, the FCC is not chartered to simply “go around doing good.”[18]
Truth in Billing, Slamming, and Cramming. The FCC maintains that it is “important for the Commission to understand specifically how applicants will ensure that consumers continue to receive the benefits of these protections during the experiment.”[19] The incentives for slamming and cramming—abusive call-routing arbitrage techniques—are predictable side effects of ICC. Eliminating incentives for such practices can dispel these fears.
Local-Number Portability. The FCC says that regardless of the addressing scheme, the “Commission’s current number portability rules and policies will apply to any service-based experiment.”[20] While this is sensible enough, the end of the telephone network does imply that we should see the end of the telephone number at some point. Phone numbers function as street addresses, but we need identifiers that relate to persons rather than places. These exist inside the legacy network, as they must for portability and mobility, but these internal identifiers will need to be exported in human-rememberable form.
Routing. Rural-call completion is a current problem for the telephone network, so the FCC demands that “calls are successfully completed as emphasized in various Commission orders, including the RCC Order and the USF/ICC Transformation Order.”[21] Again, there are larger problems with the transition from legacy telephone service to even its most primitive IP-based replacement, voice-over Internet Protocol (VoIP). Technical work needs to be done to develop a standards-based framework for call routing.

The FCC’s 114-page transitions order contains 33 instances of the verb “to preserve” in its various conjugations. The emphasis within the order is very clearly to prevent the transition from the telephone network to the pervasive IP broadband network from happening too rapidly. The commission would very strongly prefer carriers to maintain the legacy network as long as possible, despite its staggering operational costs.[22] Between 2006 and 2011, telephone companies “spent $81 billion on legacy networks, while just $73 billion was spent on modern broadband infrastructure.”[23]

Complying with the Rules

A month after the FCC issued its status quo–preserving order, AT&T filed a plan for experiments in two locales: Carbon Hill, AL, and Delray Beach in Kings Point, FL. As expected, the AT&T plan has less to do with running an actual experiment than with complying with the FCC’s 17 roadblocks.

The two locations are well chosen. Carbon Hill is a sparsely populated rural area and Delray Beach is a suburban locale with a high population of seniors, the group that has been slowest to adopt mobile phones and broadband IP connections. One of the signal challenges with the latter group is the use of Carterfone devices that were designed to allow digital data transmission over analog POTS.[24] These devices, enabled by the FCC’s 1968 Carterfone rules, include modems; we know them today as health monitors, home alarms, and fax machines.

“As many analysts have shown, open-access mandates suppress investment.”

As noted, the modem is a device that facilitates digital transmission across an analog network; now that networks are fully digital, the modem is clearly obsolete. Just as the transition from analog to digital TV required the development of “converter boxes” for holdouts who refused to purchase digital television sets and did not use cable TV services, devices that transform digital to analog and back to digital again will be a small part of the migration from analog telephone networks to digital broadband, but they already exist.

Public-interest groups have already made a big issue of modems in transition plans; Public Knowledge complained bitterly about the shortcomings of an emergency system deployed by Verizon in Fire Island, NY, after Hurricane Sandy: “users may be unhappily surprised to discover . . . Voice Link is not compatible with fax machines, DVR services, or credit card machines, and may not be compatible with home security services.”[25] To its credit, the FCC does not insist on modem converters for all trials but simply expresses interest in seeing how networks will handle modems. It is a widely known fact that many VoIP analog telephone adapters can accommodate limited uses of fax machines and similar devices. But the goal should be to support the application, not simply the device that supported the application on POTS networks.

As for the rest of the FCC’s rules, AT&T plans to rely on the use of VoIP and mobile telephones that are already widely used rather than experiment with NG911 and similar IP-oriented services that are not currently usable in the trial locales. It has no choice as it cannot force local PSAPs to adopt NG911. In the sense that the trials will utilize existing services, they are simply proving to the FCC what consumers already know: cell phones and VoIP are perfectly functional systems today. AT&T wisely chose locales that do not host DoD and FAA facilities so as not to run afoul of the requirements to continue supporting such centers with current technology.

Consequently, the trials will do more to educate the FCC on the capabilities of existing technologies than to push technical boundaries. The AT&T trials only become truly interesting where financial matters are concerned. The FCC insists on maintaining the universal-service status quo, which is less than coherent in the competitive context. As AT&T notes:

Unless the Commission modifies the [eligible telecommunications carrier (ETC)] requirements applicable to price cap carriers, which it should, any AT&T [incumbent local exchange carrier] that remains a legacy ETC will be saddled with service obligations (to provide Lifeline, to the extent it continues to receive frozen high cost support and stand-alone voice throughout its entire study area) that would not apply to their competitors receiving the same support. Those competitors likely will seek and obtain ETC designations covering only those areas where they actually receive CAF Phase II support. Even if AT&T’s ILECs do not accept any CAF Phase II support, they will be subject to service obligations (to offer voice telephony service and Lifeline supported services throughout the area for which they have been designated as an ETC) that will not apply to such competitors.[26]

Rationally, the FCC needs to convert Lifeline into a voucher program that eligible Americans can use as they wish rather than place the responsibility for universal service on one and only one competitive carrier in competitive markets.[27] This condition and others suggest that the FCC has substantial work to do in terms of modifying its regulations to harmonize them with the IP world; this approach is much more sensible than carrying dysfunctional regulations from the legacy network to pervasive IP broadband. Perhaps this is the greatest lesson of the transition trials.

Maximizing the IP Opportunity

For all its emphasis on preserving the status quo, the FCC does little to learn about the benefits of pervasive IP, perhaps because embracing the new inevitably shrinks the agency. When technology is general purpose, there is no longer a need for siloed regulation. When markets are competitive, there is no longer a need for guaranteed access at fixed prices to competitive networks. And when communications capabilities are rich and varied, there is no longer a need for microscopic regulations such as Carterfone and E911, which are technology specific.

“A better focus would be to take the next step and convene stakeholder groups such as public safety, defense, and aviation to move more quickly to the new networks.”

The FCC has been maddeningly slow to realize that the new technology already surpasses the old and requires more in the way of changes to legacy applications such as 911 and aviation and to legacy funding mechanisms such as universal service than it does in the way of adapting new networks to old applications. The FCC should certainly look for instances in which old applications will not work over IP networks, but its response to any such findings should be to ask how the application might be improved to take advantage of the bandwidth, mobility, and resiliency that pervasive IP offers, not to mindlessly demand backward compatibility for even the most obsolete technologies (like fax machines). There are myriad ways to capture and communicate images with today’s devices, applications, and networks.

A better focus would be to take the next step and convene stakeholder groups such as public safety, defense, and aviation to move more quickly to the new networks. The tactic of making the private sector adapt to stagnant government systems has become all too common in recent years; we need look no further than the President’s Council of Advisors on Science and Technology (PCAST)report in spectrum “sharing” between government and the private sector to see it at work.[28] The PCAST report allows government users of spectrum to continue status quo operations while allowing the private sector to use government spectrum only when government users are idle. This is not a productive adaptation of new technology, but it is a typical government reaction.

Conclusion

The IP transition is not simply the replacement of one technology by another; it is also the creation of a new market structure and a new (and much smaller) system of regulation. The FCC’s IP Technology Transition Trials Order should be substantially revised to reflect the responsibilities of the agency to accelerate the transition that is already far down the road. One important area of emphasis is to accelerate the adoption of IP technologies in the realms of public safety, defense, and aviation, and another relates to funding mechanisms to ensure universal use of pervasive networks by low-income citizens. It is later in the game than the FCC seems to think, so a wake-up call is in order.

Notes

1. Bill Schrier, “Is FirstNet Stalled?,” Government Technology, February 25, 2014, www.govtech.com/public-safety/Is-FirstNet-Stalled-GT.html.
2. Kristie Greco, “FAA to Allow Airlines to Expand Use of Personal Electronics,” press release, October 31, 2013, www.faa.gov/news/press_releases/news_story.cfm?newsId=15254.
3. Federal Communications Commission, Order, Report and Order and Further Notice of Proposed Rulemaking, Report and Order, Order and Further Notice of Proposed Rulemaking, Proposal for Ongoing Data Initiative (Washington, DC, January 31, 2014), http://transition.fcc.gov/Daily_Releases/Daily_Business/2014/db0131/FCC-14-5A1.pdf.
4. Ibid., 91.
5. Ibid.
6. Ibid., 92.
7. Ibid., 17.
8. Ibid., 93.
9. Ibid., 94.
10. Ibid.
11. Ibid., 95.
12. Ibid.
13. Ibid., 96.
14. See, for example, Robert Crandall, Jeffrey Eisenach, and Allan Ingraham, “The Long-Run Effects of Copper-Loop Unbundling and the Implications for Fiber,” Telecommunications Policy 37 (2013).
15. Federal Communications Commission, Order, Report and Order and Further Notice of Proposed Rulemaking, 23.
16. Ibid., 97.
17. Ibid., 24.
18. Stacey Higginbotham, “Net Neutrality, Nausea & Political Theater at Its Worst,” GigaOm, February 16, 2011, http://gigaom.com/2011/02/16/net-neutrality-nausea-and-political-theater-at-its-worst/.
19. Federal Communications Commission, Order, Report and Order and Further Notice of Proposed Rulemaking, 97.
20. Ibid.
21. Ibid., 25.
22. Anna-Maria Kovacs, Telecommunications Competition: The Infrastructure-Investment Race (Internet Innovation Alliance, October 8, 2013), http://internetinnovation.org/images/misc_content/study-telecommunications-competition-09072013.pdf.
23. Ibid., 20.
24. 13 FCC 2d 420 (1968).
25. Jodie Griffin, “Adding Insult to Injury for Sandy Victims: 911 Calls May Not Go through on New Verizon Phone Service,” Public Knowledge, May 13, 2013, www.publicknowledge.org/news-blog/blogs/adding-insult-to-injury-for-sandy-victims-911-calls-may-not-go-through-on-n.
26. AT&T, Wire Center Trial Operating Plan (February 27, 2014), http://apps.fcc.gov/ecfs/document/view?id=7521084111, 40.
27. Lifeline is a subsidy program that provides low-income Americans with basic telephone service.
28. Executive Office of the President, President’s Council of Advisors on Science and Technology, Realizing the Full Potential of Government-Held Spectrum to Spur Economic Growth (Washington, DC, July 20, 2012), www.whitehouse.gov/sites/default/files/microsites/ostp/pcast_spectrum_report_final_july_20_2012.pdf.

source : https://www.aei.org/research-products/report/wake-up-fcc-the-internet-protocol-transition-is-now/

EMR Health Alliance of BC

Electromagnetic Radiation in Western Canada