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In multi-radio wireless mesh networks, one node is eligible to transmit packets over multiple channels to different destination nodes simultaneously. This feature of multi-radio wireless mesh network makes high throughput for the network and increase the chance for multi path routing. This is because the multiple channel availability for transmission decreases the probability of the most elegant problem called as interference problem which is either of interflow and intraflow type. For avoiding the problem like interference and maintaining the constant network performance or increasing the performance the WMN need to consider the packet aggregation and packet forwarding. Packet aggregation is process of collecting several packets ready for transmission and sending them to the intended recipient through the channel, while the packet forwarding holds the hop-by-hop routing. But choosing the correct path among different available multiple paths is most the important factor in the both case for a routing algorithm. Hence the most challenging factor is to determine a forwarding strategy which will provide the schedule for each node for transmission within the channel. In this research work we have tried to implement two forwarding strategies for the multi path multi radio WMN as the approximate solution for the above said problem. We have implemented Global State Routing (GSR) which will consider the packet forwarding concept and Aggregation Aware Layer 2 Routing (AAL2R) which considers the both concept i.e. both packet forwarding and packet aggregation. After the successful implementation the network performance has been measured by means of simulation study.

We propose a three-stage load balancing packet switch and its configuration scheme. The input- and central-stage switches are bufferless crossbars, and the output-stage switches are buffered crossbars. We call this switch ThRee-stage Clos-network swItch with queues at the middle stage and DEtermiNisTic scheduling (TRIDENT), and the switch is cell based. The proposed configuration scheme uses predetermined and periodic interconnection patterns in the input and central modules to load-balance and route traffic, therefore; it has low configuration complexity. The operation of the switch includes a mechanism applied at input and output modules to forward cells in sequence. TRIDENT achieves 100% throughput under uniform and nonuniform admissible traffic with independent and identical distributions (i.i.d.). The switch achieves this high performance using a low-complexity architecture while performing in-sequence forwarding and no central-stage expansion or memory speedup. Our discussion includes throughput analysis, where we describe the operations the configuration mechanism performs on the traffic traversing the switch, and proof of in-sequence forwarding. We present a simulation analysis as a practical demonstration of the switch performance under uniform and nonuniform i.i.d. traffic., Comment: Original manuscript, IEEE Transactions on Communications, 2019. arXiv admin note: text overlap with arXiv:1812.11650

In this paper, a packet switch architecture for mesh-connected multiprocessors based on the use of a set of in-put FIFO buffers and an output register matrix controlled by a novel distributed timing-based scheduling scheme is proposed. Simple static routing is assumed, with each packet split into a set of independently routed w-bit-wide flits. The device achieves at least 78% throughput for uniformly distributed traffic and an asymptot-ic higher bound of 100%. In contrast to the state-of-the-art VOQ-based switch architectures, the proposed switch is shown to reach its maximum throughput with no internal speedup required and has an order of mag-nitude lower hardware complexity. Compared to existing buffered crossbar non-VOQ switches with typical flit scheduling mechanisms, the proposed device demonstrates slightly higher throughput and substantially short-er delays in some practically important cases.

With the applications of Internet of Things (IoT) for smart cities, the real-time performance for a large number of network packets is facing serious challenge. Thus, how to improve the emergency response has become a critical issue. However, traditional packet scheduling algorithms cannot meet the requirements of the large-scale IoT system for smart cities. To address this shortcoming, this paper proposes EARS, an efficient data-emergency-aware packet scheduling scheme for smart cities. EARS describes the packet emergency information with the packet priority and deadline. Each source node informs the destination node of the packet emergency information before sending the packets. The destination node determines the packet scheduling sequence and processing sequence according to emergency information. Moreover, this paper compares EARS with a first-come, first-served, multilevel queue algorithm and a dynamic multilevel priority packet scheduling algorithm. Simulation results show that EARS outperforms these previous scheduling algorithms in terms of packet loss rate, average packet waiting time, and average packet end-to-end delay.

It is important to develop high performance packet switches that are highly scalable. Among the popular solutions are input queued (IQ) switches and load balanced Birkhoff-von Neumann (LB-BvN) switches. However, both solutions have their drawbacks. Switch configuration pattern in IQ switches is random which can limit the supported port speed. On the other hand, LB-BvN switches require two switching stages which increase the overall cost. Also, some LB-BvN solutions suffer from the packet out of sequence problem. In this paper, we propose a novel packet switch architecture that combines the best properties of the IQ and LB-BvN switches and eliminates their drawbacks.

Load-balanced switch architectures are known to be scalable in both size and speed, which is of interest due to the continued exponential growth in Internet traffic. However, the main drawback of load-balanced switches is that packets can depart out of order from the switch. Randomized load-balancing of application flows by means of hashing on the packet header is a well-known simple solution to this packet reordering problem in which all packets belonging to the same application flow are routed through the same intermediate port and hence the same path through the switch. Unfortunately, this method of load-balancing can lead to instability, depending on the mix of flow sizes and durations in the group of flows that gets randomly assigned to route through the same intermediate port. In this paper, we show that the randomized load-balancing of application flows can be enhanced to provably guarantee both stability and packet ordering by extending the approach with safety mechanisms that can uniformly diffuse packets across the switch whenever there is a build-up of packets waiting to route through the some intermediate port. Although simple and intuitive, our experimental results show that our extended randomized load-balancing approach significantly outperforms existing load-balanced switch architectures.

The main objective of this paper is to propose a low complexity Heuristic Based Application Specific Packet Classification (HASPC) algorithm that ensures wire speed packet classification to prevent the delay and loss of multimedia packets. With the exponential growth in the link capacity, diversified services offered by the Internet and the complexities of the packet routing algorithms, wire speed classification in each router has become a bottleneck at high speed interfaces. Embedded, Network Processors (NPs) have emerged as an aid to the router for effectively processing the packets with speed and flexibility. The effectiveness of the proposed algorithm has been verified using Intel’s IXP 2400 NP simulator. The improvement in throughput of HASPC with respect to other existing algorithms varies from around 17–86%. The complexity involved is also independent of the packet size. Thus the proposed HASPC has better efficiency in supporting multimedia applications.

The paper is concerned with the problem of calculating the bound of the throughput (THR) of a crossbar packet switch. For this purpose a suitable numerical procedure is used. The input data for the procedure are the results of computer simulations executed on a grid-computational structure (www.hpc.acad.bg). The modeling of the THR uses MiMa-algorithm for a crossbar packet switch, specified by the apparatus of Generalized Nets. For studying the stability of the numerical procedure we use a modified family of patterns for i.i.d. Bernoulli uniform load traffic simulation. The obtained results show that the numerical procedure is stable which means that small input perturbations result in small changes in the output.

Battery-Free Wireless Sensor Networks (BF-WSNs) have become increasingly useful for many applications and how to ensure timely information exchange between nodes in IP networks and those in BF-WSNs is indispensable. The 6LoWPAN protocol is usually used to deliver IPv6 packets over IEEE 802.15.4 based WSNs, and has resolved the size mismatching problem between IPv6 packets and 802.15.4 Medium Access Control (MAC) frames by using packet fragmentation scheme to break an IPv6 packet into multiple small pieces with each fitted into a single 802.15.4 MAC frame. Unfortunately, IPv6 packets in BF-WSNs may suffer from intolerable delay for timely reassembling back to IPv6 packets. In this paper, we present a Latency Aware IPv6 Packet Delivery (LAID) scheme to reduce such IPv6 packet latency while maintaining high packet delivery ratio. Our LAID considers charging time, data rate, and the Maximum Number of Transmission Trials (MNTT) used in the IEEE 802.15.4 MAC layer so that the minimum latency can be achieved by optimizing the pairing of data rate and MNTT. In addition, we apply network coding to improve packet delivery reliability. Our analysis shows that the proposed LAID significantly outperforms existing schemes with fixed data rates in terms of IPv6 packet latency.

Objectives: Current network card buffer optimizations are focusing on optimal configuration of transmission's sender with singular buffer. However, there exists receiver-oriented network card module with multiple buffers. In our research, we mirrored PF_RING, which alters the traditional packet processing that requires copying the packets to application space. Methods/Statistical Analysis: PF_RING provides buffers for higher layer applications to access packets directly. Findings: Each buffer's capacity, transmission size, packet size, number of packets, and number of applications give raise to the question on the number of buffers required, because it affects the duration of packets read by the applications. Optimal number of buffers is therefore needed to generate minimum packet reading duration of the applications. Application/Improvements: We propose mathematical models to represent the simulation of packet buffering in a multibuffer receiver's network card. Our simulation models are used to determine the optimal number of buffers for specific network transmission with distinct properties, which include transmission size, packet size, and number of packets.

In 4G, LTE-Advanced specifies the key objective that the gigabit data rate for real-time video streaming can be transmitted under a high mobility scenario; thus, packet scheduling and radio resource management become the critical techniques that should be addressed effectively. Additionally, the mechanisms of relaying and the OFDMA coding have been certainly adopted in LTE-Advanced and IEEE 802.16 j/m for the purposes of increasing the wireless service coverage and improving signal quality of UEs nearing the cell boundaries. Several studies propose some improvements for the relaying-based packet scheduling, but suffer from long packet delay, high packet dropping probability moderate system capacity, and degrading QoS of real-time packet transmissions. This paper thus proposes an Adaptive LTE-Advanced cross-layer packet Scheduling (ALS) to guarantee real-time high-speed packet service for LTE-Advanced. ALS consists of two mechanisms: (1) Adaptive Reward Priority Scheduling: the cross layer-based adaptive packet scheduling at the MAC layer and (2) Dynamic Resource Allocation algorithm: the efficient radio resource allocation at the PHY layer. Numerical results demonstrate ALS outperforms the compared approaches in system capacity, packet dropping probability, average packet delay, etc.

This paper proposes the end-to-end security scheme with packet key mechanism to perform ciphering of user traffic between two UEs attached to the different LTE networks. In LTE system, each UE derives its master key after a mutual authentication is performed between the UE and its local LTE network. In this paper, two end-to-end UEs use their own master keys to generate real-time packet keys where different packet keys are applied to encrypt packet stream data on a packet basis. Because the life cycle of the packet key is same as a packet period, the proposed security scheme significantly improves the security strength for end-to-end LTE users. As a result, this paper contributes to suggest the security scheme with packet key mechanism that can provide high level of security as well as end-to-end security for the global LTE UEs.