Maximum Packet Size Research Articles

Resilient Edge: Building an Adaptive and Resilient Multi-Communication Network for IoT Edge Using LPWAN and WiFi

Edge computing has gained attention in recent years due to the adoption of many Internet of Things (IoT) applications in domestic, industrial and wild settings. The resiliency and reliability requirements of these applications vary from noncritical (best delivery efforts) to safety-critical with time-bounded guarantees. The network connectivity of IoT edge devices remains the central critical component that needs to meet the timebounded Quality of Service (QoS) and fault-tolerance guarantees of the applications. Therefore, in this work, we systematically investigate how to meet IoT applications mixed-criticality QoS requirements in multi-communication networks. We (i) present the network resiliency requirements of IoT applications by defining a system model (ii) analyse and evaluate the bandwidth, latency, throughput, maximum packet size of many state-of-theart LPWAN technologies, such as Sigfox, LoRa, and LTE (CATM1/ NB-IoT) and Wi-Fi, (iii) implement and evaluate an adaptive system Resilient Edge and Criticality-Aware Best Fit (CABF) resource allocation algorithm to meet the application resiliency requirements using Raspberry Pi 4 and Pycom FiPy development board having five multi-communication networks.We present our findings on how to achieve 100% of the best-effort high criticality level message delivery using multi-communication networks.

Signature Split Method for a PQC-DSA Compliant with V2V Communication Standards

The development of quantum computing systems poses a great threat to the security of existing public key-based systems. As a result, the National Institute of Standards and Technology (NIST) started a Post-Quantum Cryptography (PQC) standardization project in 2015, and currently active research is being conducted to apply PQC to various cryptographic protocols. Unlike elliptic curve cryptography (ECC)-based schemes, PQC requires a large memory footprint and key/signature size. Therefore, when migrating PQC to a protocol, depending on the PQC and protocol specifications, it can be hard to migrate PQC. In the case of the WAVE protocol, it is difficult to satisfy the accuracy of a specific PQC algorithm because segmentation of the signature occurs during transmission due to the limitation of the maximum packet size. Therefore, in this paper, we present two methodologies that can apply PQC while complying with IEEE 1609.2 standards to the WAVE protocol in the V2V environment. Whereas previous migration studies have focused on designing a hybrid mode of protocols, this paper explores solutions more intuitively at the application layer of protocols. We analyzed two postquantum digital signature algorithms (Crystals-Dilithium and Falcon) and the structure of basic-safety messages (BSMs) of the V2V protocol on the size side. Through this, we propose methods that can perform an independent signature verification process without waiting for all divided signatures in the WAVE protocol. Our methodology overcomes the limitation that schemes with large signature sizes cannot be mounted into the WAVE protocol. We also note that the architecture used as an on-board unit (OBU) in an autonomous driving environment is mainly a microprocessor. We investigated an optimized PQC implementation in the OBU environment and simulated our methodology with the V2Verifier. Finally, we measured the accurate latency through simulation in Jetson Xavier, which is mainly used as an OBU in the V2V communication network.

End-to-end communication protocol in IoT-enabled ZigBee network: Investigation and performance analysis

ZigBee is the prominent technology on the Internet of Things that enables smart applications and services. However, this technology forms personal area networks, which will not directly communicate with internet end users. The IoT-enabled Zigbee devices cannot handle the IPv6 packets, which have a maximum packet size of 1280 bytes, and the transmission of IPv6 packets over ZigBee-based IEEE 802.15.4 networks, which will be performed using a gateway. via the ZigBee coordinator. The gateways and the ZigBee coordinator must complete the neighbor discovery process, which increases the coordinator’s complexity. Additional ZigBee devices suffer from header size problems, routing structures, and data forwarding issues. This paper presents an efficient end-to-end communication protocol for IoT-enabled ZigBee devices and with an Internet host using the 6LoWPAN protocol. This 6LoWPAN connects IP-based infrastructures with a collection of Zigbee devices that provide end-to-end communication to route the IPv6 packets into ZigBee-enabled IoT networks. Next, we proposed the RPL-AODV routing protocol, which refers to the capacity to forward or route the data packets from one Zigbee device to the 6LoWPAN Boarder Router (6BR) via several hops. This proposed routing protocol combines the advantages of RPL and AODV routing protocols in ZigBee devices of IoT networks that establish the path from the origin node to the target node on an on-demand basis. Finally, we evaluated the performance of this protocol with various metrics and found improved results compared to existing protocols.

Reduction of Padding Overhead for RLNC Media Distribution With Variable Size Packets

Random linear network coding (RLNC) can enhance the reliability of multimedia transmissions over lossy communication channels. However, RLNC has been designed for equal size packets, while many efficient multimedia compression schemes, such as variable bitrate (VBR) video compression, produce unequal packet sizes. Padding the unequal packet sizes with zeros to the maximum packet size creates an overhead on the order of 20%–50% or more for typical VBR videos. Previous padding overhead reduction approaches have focused on packing the unequal packet sizes into fixed size packets, e.g., through packet bundling or chaining and fragmentation. We introduce an alternative padding reduction approach based on coding macro-symbols (MSs), whereby an MS is a fixed-sized part of a packet. In particular, we introduce a new class of RLNC, namely MS RLNC which conducts RLNC across columns of MSs, instead of the conventional RLNC across columns of complete packets of equal size. Judiciously arranging the source packets into columns of MSs, e.g., through shifting the source packets horizontally relative to each other, supports favorable MS RLNC coding properties. We specify the MS RLNC encoding and decoding mechanisms and analyze their complexity for a range of specific MS arrangement strategies within the class of MS RLNC. We conduct a comprehensive padding overhead evaluation encompassing both previous approaches of packing the unequal size packets into fixed size packets as well as the novel MS RLNC approaches with long VBR video frame size traces. We find that for small RLNC generation sizes that support low network transport delays, MS RLNC achieves the lowest padding overheads; while for large generation sizes, both the previous packing approaches and the novel MS RLNC approaches effectively reduce the padding overhead.

Efficient packet scheduling technique for data merging in wireless sensor networks

Wireless Sensor Networks (WSNs) has become a popular research topic due to its resource constraints. Energy consumption and transmission delay is crucial requirement to be handled to enhance the popularity of WSNs. In order to overcome these issues, we have proposed an Efficient Packet Scheduling Technique for Data Merging in WSNs. Packet scheduling is done by using three levels of priority queue and to reduce the transmission delay. Real-time data packets are placed in high priority queue and Non real-time data packets based on local or remote data are placed on other queues. In this paper, we have used Time Division Multiple Access (TDMA) scheme to efficiently determine the priority of the packet at each level and transmit the data packets from lower level to higher level through intermediate nodes. To reduce the number of transmission, efficient data merge technique is used to merge the data packet in intermediate nodes which has same destination node. Data merge utilize the maximum packet size by appending the merged packets with received packets till the maximum packet size or maximum waiting time is reached. Real- time data packets are directly forwarded to the next node without applying data merge. The performance is evaluated under various metrics like packet delivery ratio, packet drop, energy consumption and delay based on changing the number of nodes and transmission rate. Our results show significant reduction in various performance metrics

Channel Diagnostics for Wireless Sensor Networks in Harsh Industrial Environments

Wireless sensor network communication in industrial environments is compromised by interference, multipath fading, and signal attenuation. In that respect, accurate channel diagnostics is imperative to selecting the adequate countermeasures. This paper presents the lightweight packet error discriminator (LPED) that infers the wireless link condition by distinguishing between errors caused by multipath fading and attenuation, and those inflicted by interfering wideband single-channel communication systems (e.g., IEEE 802.11b/g), based on the differences in their error footprints. The LPED uses forward error correction in a novel context, namely, to determine the symbol error density, which is then fed to a discriminator for error source classification. The classification criteria are derived from an extensive set of error traces collected in three different types of industrial environments, and verified on a newly collected set of error traces. The proposed solution is evaluated both offline and online, in terms of classification accuracy, speed of channel diagnostics, and execution time. The results show that in ≥91% of cases, a single packet is sufficient for a correct channel diagnosis, accelerating link state inference by at least 270%, compared with the relevant state-of-the-art approaches. The execution time of LPED, for the worst case of packet corruption and maximum packet size, is below 30 ms with ≤3% of device memory consumption. Finally, live tests in an industrial environment show that LPED quickly recovers from link outage, by losing up to two packets on average, which is only one packet above the theoretical minimum.

Competitive buffer management with packet dependencies

We introduce the problem of managing a FIFO buffer of bounded space, where arriving packets have dependencies among them. Our model is motivated by the scenario where large data frames must be split into multiple packets, because maximum packet size is limited by data-link restrictions. A frame is considered useful only if sufficiently many of its constituent packets are delivered. The buffer management algorithm decides, in case of overflow, which packets to discard and which to keep in the buffer. The goal of the buffer management algorithm is to maximize throughput of useful frames. This problem has a variety of applications, e.g., Internet video streaming, where video frames are segmented and encapsulated in IP packets sent over the Internet. We study the complexity of the above problem in both the offline and online settings. We give upper and lower bounds on the performance of algorithms using competitive analysis.

Modeling and Performance Analysis of Route-Over and Mesh-Under Routing Schemes in 6LoWPAN under Error-Prone Channel Condition

6LoWPAN technology has attracted extensive attention recently. It is because 6LoWPAN is one of Internet of Things standard and it adapts to IPv6 protocol stack over low-rate wireless personal area network, such as IEEE 802.15.4. One view is that IP architecture is not suitable for low-rate wireless personal area network. It is a challenge to implement the IPv6 protocol stack into IEEE 802.15.4 devices due to that the size of IPv6 packet is much larger than the maximum packet size of IEEE 802.15.4 in data link layer. In order to solve this problem, 6LoWPAN provides header compression to reduce the transmission overhead for IP packets. In addition, two selected routing schemes, mesh-under and route-over routing schemes, are also proposed in 6LoWPAN to forward IP fragmentations under IEEE 802.15.4 radio link. The distinction is based on which layer of the 6LoWPAN protocol stack is in charge of routing decisions. In route-over routing scheme, the routing distinction is taken at the network layer and, in mesh-under, is taken by the adaptation layer. Thus, the goal of this research is to understand the performance of two routing schemes in 6LoWPAN under error-prone channel condition.

Deployment of TCP University of Bridgeport (UB) to Control Law Enforcement Department over Wireless Mesh Network

Transmission Control Protocol (TCP) is the most reliable protocol. That was previously introduced for wired networks only. Lately the TCP started to act poorly for several factors due to the advent of wireless network. The represented factors which need to be addressed are recovery mechanism, backup mechanism, mobility, congestion window and maximum packet size. Based on existing variants, new were introduced. The most two debated variants are Vegas and Westwood which motivated many researches. However, the number of studies proved that Vegas could perform more efficiency than other variants during the congested network whereas Westwood could consume less bandwidth. Hence, in our previous publications, we already proved by integrating some features of Vegas and Westwood to get better and more stable variant even in high congested network. It is called TCP University of Bridgeport (TCP-UB).Based on a previous simulation, TCP-UB proved a high efficiency, less bandwidth consumption and stability from static and mobility point of view. Therefore, in this paper we are using NS2 simulator to perform TCP-UB over wireless mesh network supported with manhattan mobility model. It provides robust and faster transmission service among several police stations in Connecticut, USA.Furthermore, we are comparing TCP-UB with Vegas and Westwood from a static and mobility point of view based on bandwidth consumption and congestion window scenario. On the basis of findings, we validate that TCP-UB is also better performer even over wireless mesh network.

TCP-UB: A New Congestion Aware Transmission Control Protocol Variant

Transmission control protocol (TCP) is a connection oriented protocol for several types of distributed applications. TCP is reliable particularly for traditional fixed networks. With emergence of faster wireless networks, TCP has been performing poorly in its original format. The performance of TCP is affected due to assorted factors including congestion window, maximum packet size, retry limit, recovery mechanism, backup mechanism and mobility. To overcome deficiency of original TCP, Several modifications have been introduced to improve network quality. The mobility is a major hurdle in degrading the performance of mobile wireless networks. In this paper, we introduce and implement new TCP variant University of Bridgeport (UB) that combines the features of TCP Westwood and Vegas. We examine the performance of TCP-UB, Vegas and Westwood using different realistic scenarios. NS2 simulator demonstrates the stability of TCP-UB as compared with TCP Vegas and Westwood in highly congested networks from the mobility point of view.

Improving throughput in WiMAX communication at vehicular speeds

WiMAX technology has emerged as an exciting technology for next generation broadband wireless network with promises to offer high throughput and long coverage. WiMAX, however, has yet to prove its merits when the wireless nodes are not fixed and move at high vehicular speeds. Recent studies suggest that WiMAX offers limited throughput when a mobile node travels at vehicular speeds. Multipath fading causes high bit error rates at the receiver and is considered the main reason behind low throughput at high vehicular speeds. Bit error rates and maximum packet size govern the packet error rates, and error recovery for higher number of corrupted packets is not an attractive option for many real-time applications with tight delay and jitter constraints. In this paper, we present a mathematical model for estimating bit error rates in WiMAX communication at vehicular speeds. The estimated bit error probability is taken into account for proactively computing an optimum packet size that offers the best chance of achieving improved throughput. We further propose a model that can be used to increase the utility of real-time wireless applications e.g., video surveillance systems in public train based on the knowledge of estimated transmission rates. We simulated the proposed and other standard schemes for a centralized video surveillance system in a public train where the train moves at high speeds and sends real-time video data to a central control room through wireless channels. The results show that the proposed scheme achieves significantly higher throughput, lower jitter and higher utility gain compared to the standard schemes.

Synchronization, retiming and time-division multiplexing of an asynchronous 10 Gigabit NRZ Ethernet packet to terabit Ethernet

An asynchronous 10 Gb/s Ethernet packet with maximum packet size of 1518 bytes is synchronized and retimed to a master clock with 200 kHz frequency offset using a time lens. The NRZ packet is simultaneously converted into an RZ packet, then further pulse compressed to a FWHM of 400 fs and finally time-division multiplexed with a serial 1.28 Tb/s signal including a vacant time slot, thus forming a 1.29 Tb/s time-division multiplexed serial signal. Error-free performance of synchronizing, retiming, time-division multiplexing to a Terabit data stream and finally demultiplexing back to 10 Gb/s of the Ethernet packet is achieved.

When In-Network Processing Meets Time: Complexity and Effects of Joint Optimization in Wireless Sensor Networks

As sensornets are increasingly being deployed in mission-critical applications, it becomes imperative that we consider application QoS requirements in in-network processing (INP). Toward understanding the complexity of joint QoS and INP optimization, we study the problem of jointly optimizing packet packing (i.e., aggregating shorter packets into longer ones) and the timeliness of data delivery. We identify the conditions under which the problem is strong NP-hard, and we find that the problem complexity heavily depends on aggregation constraints (in particular, maximum packet size and reaggregation tolerance) instead of network and traffic properties. For cases when the problem is NP-hard, we show that there is no polynomial-time approximation scheme (PTAS); for cases when the problem can be solved in polynomial time, we design polynomial time, offline algorithms for finding the optimal packet packing schemes. To understand the impact of joint QoS and INP optimization on sensornet performance, we design a distributed, online protocol tPack that schedules packet transmissions to maximize the local utility of packet packing at each node. Using a testbed of 130 TelosB motes, we experimentally evaluate the properties of tPack. We find that jointly optimizing data delivery timeliness and packet packing and considering real-world aggregation constraints significantly improve network performance. Our findings shed light on the challenges, benefits, and solutions of joint QoS and INP optimization, and they also suggest open problems for future research.

Optical Synchronization of a 10-G Ethernet Packet and Time-Division Multiplexing to a 50-Gb/s Signal Using an Optical Time Lens

A 10-G Ethernet packet with maximum packet size of 1518 bytes is synchronized to a master clock with 200-kHz frequency offset using a time lens. The input 10-Gb/s nonreturn-to-zero packet is at the same time converted into a return-to-zero (RZ) packet with a pulsewidth of 10 ps and then time-division multiplexed with four 10-Gb/s optical time-division-multiplexing (OTDM) channels, thus constituting a 50-Gb/s OTDM serial signal. Error-free performances of the synchronized RZ packet and demultiplexed packet from the aggregated 50-Gb/s OTDM signal are achieved.

Exact GPS Simulation and Optimal Fair Scheduling With Logarithmic Complexity

Generalized processor sharing (GPS) is a fluid scheduling policy providing perfect fairness over both constant-rate and variable-rate links. The minimum deviation (lead/lag) with respect to the GPS service achievable by a packet scheduler is one maximum packet size. To the best of our knowledge, the only packet scheduler guaranteeing the minimum deviation is worst-case fair weighted fair queueing , which requires on-line GPS simulation. Existing algorithms to perform GPS simulation have worst-case computational complexity per packet transmission (being the number of competing flows). Hence, has been charged for complexity too. However it has been proven that the lower bound complexity to guarantee deviation is, yet a scheduler achieving such a result has remained elusive so far. In this paper, we present L-GPS, an algorithm that performs exact GPS simulation with worst-case complexity and small constants. As such it improves the complexity of all the packet schedulers based on GPS simulation. We also present , an implementation of based on L-GPS. has complexity with small constants, and, since it achieves the minimum possible deviation, it does match the aforementioned complexity lower bound. Furthermore, both L-GPS and comply with constant-rate as well as variable-rate links. We assess the effectiveness of both algorithms by simulating real-world scenarios.

Throughput and Delay Analysis of Unslotted IEEE 802.15.4

The IEEE 802.15.4 standard is designed as a low power and low data rate protocol offering high reliability. It defines a beaconed and unbeaconed version. In this work, we analyze the maximum throughput and minimum delay of the unbeaconed or unslotted version of the protocol. First, the most important features are described. Then the exact formula for the throughput and delay of a direct transmission between one sender and one receiver is given. This is done for the different frequency ranges and address structures used in IEEE 802.15.4. The analysis is limited to the unslotted version as this one experiences the lowest overhead. It is shown that the maximum throughput depends on the packet size. In the 2.4 GHz band, a bandwidth efficiency of 64.9% is reached when the maximum packet size is used. Further we describe the influence of the back off interval. A significant gain is found when the backs off parameters are altered. We have measured the throughput experimentally in order to compare the theoretical analysis with real-life examples.

Blocking Probability Analysis for Packet Circuit Emulation Services

Standardization of pseudo-wire and circuit emulation services on IP packet networks is underway. The ability to quickly find circuits in networks supporting circuit emulation is directly computed using blocking probability analysis. When all of the sequenced flows have the same maximum packet size, i.e., they are homogeneous, blocking probabilities are computed using Erlang's B formula. This paper describes analysis tools for the heterogeneous case and introduces the concept of steady-state fragmentation blocking probability, which controls the size of state transition diagrams used in the analysis. Simulation results using these tools are presented.

An mK×nK bouwblok CCD image sensor family. II. Characterization

For pt. I see ibid., vol. 49, no. 3, p. 361-69 (2002). This paper characterizes the performance of four sensors from the bouwblok family. The original design meets the key original design goals, including the maximum packet size Q/sub max/, readout speed, antiblooming protection, and optical performance. Three-level vertical clocks are used to reach more than 12-bits linear dynamic range at 60/spl deg/C, and the binning capacity is limited at the floating diffusion and in the horizontal register. The dark current is low for a modern non-MPP (multiphase pinned) technology (0.3 nA/cm/sup 2/). The performance of the design is consistent (for identical clocking conditions at the pixel) across all members of the family.

QoS-Aware Fair Queuing: A Low Overhead Packet Scheduling Discipline for Networked Multimedia Environments

Discrete service disciplines have been shown capable of emulating the ideal Generalized Processor Sharing (GPS) discipline within one maximum-sized packet's transmission time. As a result, the accuracy of such schemes increases with improvements in link speed due to the corresponding reduction in packet transmission delay. However, the merits of such accuracy diminish with improvements in link speed as the impact on call admission decisions decreases. Meanwhile, overhead, in terms of the number of scheduling decisions to be made per unit time, increases with the number of packets transmitted. In response, this paper will present the QoS-Aware Fair Queuing (QFQ) service discipline which enables emulation servers to dynamically “tune” their service quanta based upon the QoS requirements of their currently supported applications rather than the network's maximum packet size. The paper will also demonstrate how the overhead of a GPS emulation server can be reduced in high speed networks without jeopardizing QoS guarantees or adversely impacting fairness.

An efficient traffic control scheme for TCP over ATM GFR services

In ATM networks, the guaranteed frame rate (GFR) service category has been defined to support user applications which are neither able to specify the range of traffic parameter values, nor able to comply with the behavior rules. It provides a packet-level rate guarantee with a given maximum packet size. The service specifies that the excessive traffic from a user should share the available resource fairly. In this paper, we investigate TCP/IP packet transmission over ATM by using a selective packet-discard strategy with tracking of the available buffer space and a packet push-out buffering scheme to accommodate the GFR service. The simulation results show that our proposed method fulfills the requirements of GFR service as well as improves the TCP throughput under the common FIFO scheduling. A feasible implementation approach is also addressed.