Ah Protocol Research Articles

Clinical outcomes of challenging out-of-hospital hypothermia management: A retrospective assessment of DOKEI protocol

BackgroundAccidental hypothermia (AH) is a major cause of death in mountainous areas globally, and the second highest of mountaineering deaths in Japan, accounting for 37 % in Hokkaido. Managing AH is a significant challenge, particularly when adverse weather complicates the application of recommended rewarming and rapid transfer. To address this, the Hokkaido Police Organization (DOKEI) AH protocol was applied in Hokkaido's remote areas from 2011 to 2022, integrating high-temperature active external rewarming (HT-AER) with on-site sustained treatment. MethodsThis study retrospectively analyzed the rescue reports and hospital records of hypothermia patients treated postprotocol, excluding patients with cold exposure, undetectable vital signs at rescue, and inadequate documentation. Protocol adherence and outcomes—hypothermia stage, cardiocirculatory collapse, survival, and neurological status—were assessed. ResultsAmong the 60 protocol-treated patients (19–74 years, 85 % male), 14 had stage 2 hypothermia, and 3 had stage 3 hypothermia. HT-AER was applied in 96.7 % of the patients. A total of 98.3 % of patients improved before handover without cardiac arrest (CA) or extracorporeal life support (ECLS). Comparatively, ten preprotocol patients (18–60 years, 70 % male) had two CAs, one fatal and six with no improvement. ConclusionThe DOKEI AH protocol demonstrates feasibility in managing stages 1–3 hypothermia, enhancing survival and neurological recovery, and can offer a vital option in challenging AH rescue scenarios.

An adaptive centralized authentication control method to reduce association delay in the IoT 802.11ah protocol

An adaptive centralized authentication control method to reduce association delay in the IoT 802.11ah protocol

Selfish Behavior in IEEE 802.11ah Networks: A Detection Algorithm and Mitigation Strategies.

One of the latest protocols developed for the Internet of Things networks is IEEE 802.11ah, proposed by the WiFi Alliance. The new channel access mechanism in IEEE 802.11ah, which is called Restricted Access Window, aims at reducing the contention between the stations by allowing only selected stations to transmit data at certain time slots. Stations may exhibit selfish behavior to maximize their own throughput. This will come at the cost of the overall network quality of service. In this paper, we first analyze the default behavior of the IEEE 802.11ah protocol in terms of fairness. We then introduce various percentages of selfish stations and observe how the network’s quality of service in terms of fairness, throughput and packet-loss are affected. After establishing the inherent fairness of IEEE 802.11ah, we analyze applicability of two existing selfish behavior detection algorithms designed for IEEE 802.11 to the IEEE 802.11ah protocol. Due to their poor performance, we propose a new definition of ’selfish behavior’ specifically for IEEE 802.11ah, based on which we present a new algorithm for detecting selfish behavior. To combat selfish behavior and to create a better fairness, throughput and lower packet loss, we consequently present a novel mitigation algorithm called Selfish Stations Quarantine Punishment Algorithm (SSQPA). The proposed algorithm takes advantage of the RAW grouping to isolate selfish stations from the honest stations, thus mitigating the effect of the selfish behavior. SSQPA comes in two variants: honest stations-centric and network-centric. Our experimental results show that both variants can successfully mitigate selfish behavior effects in IEEE 802.11ah networks and either one can be used depending on the goal of the network.

A Feasibility Analysis of the Use of IEEE 802.11ah to extend 4G Network Coverage

The 4G LTE network has been launched in many countries including Indonesia, and all telecommunications operators are competing to expand their service coverage. Due to various reasons, there are a lot of areas that remains uncovered by the 4G LTE network. With the increase in cellular traffic, operators must continue to improve their service coverage. One of the scenarios to expand the service coverage is by offloading the traffic to a more cost-effective 802.11ah network in which one 802.11ah access point can serve thousands of mobile devices and support the Machine-to-Machine (M2M)/Internet of Things (IoT) communication. This study simulates the effect of the number of nodes on MCS performance evaluation of the 802.11ah protocol. The simulation is conducted by utilizing NS3 software to evaluate the throughput, delay, packet delivery ratio and energy consumption. This study also simulates 802.11ah coverage prediction to expand the LTE networks by utilizing Atoll Radio Planning Software. The results show that the performance obtained by varying the number of nodes/users from 100 to 1000 nodes is technically acceptable. In addition, the service coverage of 802.11ah network can solve the problem of blank spot area.

Probability-based opportunity dynamic adaptation (PODA) of contention window for home M2M networks

With the emergence of the Internet of Things (IoT), the growing use of autonomous sensing and actuating devices in areas such as smart grid, e-healthcare, home networking, and machine-to-machine (M2M) communication has become an important communication paradigm. Nonetheless, to fully exploit the applications facilitated by M2M communication, service requirements such as data throughput, scalability and reliability must be in place. This paper proposes a new backoff adaptation mechanism known as probability-based opportunity dynamic adaptation (PODA) for M2M communication using the IEEE 802.11ah protocol. The proposed PODA is an enhanced version of the binary exponential backoff (BEB) where a station estimates the number of contending stations in a distributed manner and adaptively tunes its minimum contention window (CW) prior to the contention process for better network throughput and packet delivery ratio. Owing to its great flexibility and ease of implementation, BEB has been extended to home M2M communication such as wireless sensor networks and smart grid technologies without relying on wide area communication. However, the current form of BEB has its shortcomings in the emerging M2M paradigm. The adaptation of CW in PODA is based on the optimal station's access opportunity to improve network performance instead of direct CW scaling. Using the proposed adaptation method, the network throughput can be improved by as much as 18 percent in the home M2M network studied, while enhancing network reliability and fairness.

Performance Evaluation of Heterogeneous IoT Nodes With Differentiated QoS in IEEE 802.11ah RAW Mechanism

IEEE 802.11ah protocol is specifically designed to provide network connectivity to a large number of energy efficient heterogeneous quality of service (QoS) Internet of things (IoT) devices. Restricted access window (RAW) mechanism of the protocol is an innovative feature that aims at reducing medium access contention by slotting the beacon interval and allowing limited number of nodes to contend in a specific slot. In this paper, we evaluate important medium access control (MAC) layer performance metrics of differentiated QoS IoT nodes in the IEEE 802.11ah RAW mechanism. Our analysis evaluates the feasibility of coexistence of priority and nonpriority traffic in IoT devices without degrading network performance.

Emerging Wireless Technologies in the Internet of Things : A Comparative Study

The Internet of Things (IoT) incorporates multiple long-range, short-range, and personal area wireless networks and technologies into the designs of IoT applications. This enables numerous business opportunities in fields as diverse as e-health, smart cities, smart homes, among many others. This research analyses some of the major evolving and enabling wireless technologies in the IoT. Particularly, it focuses on ZigBee, 6LoWPAN, Bluetooth Low Energy, LoRa, and the different versions of Wi-Fi including the recent IEEE 802.11ah protocol. The studies evaluate the capabilities and behaviours of these technologies regarding various metrics including the data range and rate, network size, RF Channels and Bandwidth, and power consumption. It is concluded that there is a need to develop a multifaceted technology approach to enable interoperable and secure communications in the IoT.

An FPGA-based reconfigurable IPSec AH core with efficient implementation of SHA-3 for high speed IoT applications

The need for securing data across the Internet has become a fundamental issue over the last decade. The Internet protocol security IPSec standard has been developed as one solution to the problem of end-to-end secure communications. IPSec implementation is computationally intensive and can significantly limit the performance of high-speed networks. To overcome this speed issue, hardware implementations of IPSec offer the best solution. This work presents a field programmable gate array-based reconfigurable IPSec authentication header AH core. AH is one of the two main IPSec protocols, namely, AH and encapsulating security payload, and it supports both transport and tunnel modes of operations. For the AH protocol, a newly selected cryptographic hash function called secure hash algorithm-3 SHA-3 is implemented and used in this work. SHA-3 is implemented using a unique two-phase implementation approach that combines all the steps of SHA-3. The resultant equations, after combining the SHA-3 steps, are implemented as a proposed high-speed architecture, which results in data throughput in the gigabits per second range. The AH core proposed here outperforms other published techniques and is capable of supporting IPv4 datagrams for both modes of operation transport and tunnel and also can be used to provide security services for Internet of things applications that require high data throughput speeds. Copyright © 2016 John Wiley & Sons, Ltd.

Reliable and Efficient Access for Alarm-Initiated and Regular M2M Traffic in IEEE 802.11ah Systems

IEEE 802.11ah is a novel WiFi-based protocol, aiming to provide an access solution for the machine-to-machine (M2M) communications. In this paper, we propose an adaptive access mechanism that can be seamlessly incorporated into IEEE 802.11ah protocol operation and that supports all potential M2M reporting regimes, which are periodic, on-demand, and alarm reporting. The proposed access method is based on a periodically reoccurring pool of time slots, whose size is proactively determined on the basis of the reporting activity in the cell. We show that it is possible to both efficiently and reliably resolve all reporting stations in the cell, within the limits of the allowed deadlines. As a side result, we also provide a rationale for modeling the interarrival time in alarm events by using the Beta distribution, a model that is considered in the 3GPP standardization.

An IPSec Accelerator Design for a 10Gbps In-Line Security Network Processor

The IP security protocol (IPSec) is an important and widely used security protocol in the IP layer. But the implementation of the IPSec is a computing intensive work which greatly limits the performance of the high speed network. In this paper, a high performance IPSec accelerator used in a 10Gbps in-line network security processor (NSP) is presented. The design integrates the protocol processing and the cryptographic processing; the transport/tunnel mode of the AH, ESP security protocols and the AES, HMAC-SHA-1 cryptographic algorithms are realized by hardware. An efficient partial crossbar data transfer skeleton with iSLIP scheduling algorithm is adopted to realize the maximum utilization of the computation resources in the accelerator. The number of AH, ESP, AES, HMAC-SHA-1 cores in the design can be configured to meet the different applications. By simulation, with 8 protocol IP-cores and 24 crypto IP-cores connected to the crossbar in the IPSec accelerator, the design gives a peak throughput for the AH protocol transport mode of 11.28Gbps at the average of 512 bytes packet length under a clock rate of 300MHz. The hardware verification is implemented on a Virtex-5 XC5VSX95T based FPGA board. Low power design methods are also used in the design to reduce the power dissipation.

MicroISPs: providing convenient and low-cost high-bandwidth Internet access

We present MicroISP, a novel architecture for Internet Service Providers suitable for installation in airports, hotels, conference centers, cafés, and office or apartment buildings. Users access a MicroISP via a low-cost, high-bandwidth LAN, e.g. Ethernet or WaveLAN. A router connects the MicroISP’s LAN to a shared high-bandwidth access link (e.g., DSL or cable) to a conventional ISP. For this service, a MicroISP charges its clients. The architecture supports a variety of payment methods, both offline (e.g., cash, credit card, or billing to a hotel room account) and online (e.g., eCash, SET, IBM Micro Payments, or Millicent). MicroISPs use IPSec’s IKE protocol for securely exchanging authentication keys with paying users. Paying users use IPSec’s AH protocol in tunnel mode to authenticate each packet they send. Therefore, MicroISPs can easily detect and drop packets of nonpaying users. A MicroISP must present to users a certificate signed by a recognized authority, but a user may simply present a self-signed certificate, as long as the user pays for service. Regardless of how online payment is implemented, it runs on the user’s authenticated tunnel, and therefore can be securely bound to it. The MicroISP protocol allows users to monitor and control usage and supports recovery in case of a MicroISP or user computer crash.