Chain-based routing protocols such as PEGASIS reduce redundant transmissions in Wireless Sensor Networks (WSNs), yet their static link structures and greedy neighbor selection often result in long communication links, uneven energy depletion, and premature network failure. Achieving both globally optimized chain construction and energy-balanced routing under diverse network deployments therefore remains a significant research challenge. To address these limitations, this paper proposes GWO-PEGASIS, a scalable two-stage optimization framework that integrates K-means clustering for spatial partitioning with the Grey Wolf Optimizer (GWO) to construct globally optimized intra- and inter-cluster chains under connectivity constraints. In the first stage, K-means forms spatially compact clusters based on node density, initial energy, and spatial distribution. In the second stage, GWO enables adaptive chainhead selection, balanced multihop forwarding, and improved spatial load distribution. Extensive simulations validate the effectiveness of the proposed method: GWO-PEGASIS shortens total chain length by 10.46% relative to PEGASIS, more than doubles the network lifetime, and further improves lifetime by 11.2% and 14.6% over EB-PEGASIS-SCL and MC-CRITIC-KM, respectively. It also achieves the lowest per-round energy consumption, the most balanced residual-energy distribution, and the highest throughput among all evaluated protocols. These results demonstrate that GWO-PEGASIS offers a robust, energy-efficient, and scalable routing solution for WSNs, highlighting the strong potential of swarm-intelligence-driven optimization for addressing complex topology design challenges in resource-constrained environments.

The original Wireless Arithmetic Label Switching (WALS) framework is unsuitable for MANETs with directional antennas. To overcome this limitation, we propose WALS-DA (Wireless Arithmetic Label Switching with Directional Antennas), a revised framework designed for compatibility with such environments. In WALS-DA, prime keys are no longer preassigned to individual nodes but are dynamically generated for each edge (virtual link) between adjacent nodes directional antennas. Unlike WALS, which relies on node-keys, WALS-DA employs edge-keys (a.k.a. link-keys), enabling intermediate nodes to identify specific next-hop neighbors by matching edges (directional antennas) through multiple modulo operations. To ensure backward compatibility, we also explore a hybrid scenario incorporating both omni-directional and directional antennas. Although WALS-DA introduces slightly higher label overhead compared to WALS, it remains a promising solution for specialized MANET deployments while highlighting key open issues for future research.

The integration of semantic communication technology into intelligent vehicular networks represents a promising research direction, as it significantly reduces data transmission volume and spectrum usage, addressing the high demands of transmitting large-scale visual information between vehicles. Existing studies typically assume that communicating parties share a common database. However, this assumption poses significant privacy risks, particularly in inter-vehicle scenarios. To address these challenges, we propose a federated learning-based semantic-aware communication for vehicular networks. In this approach, each intelligent vehicle locally trains a semantic communication model and uploads its model parameters to the edge server for aggregation. To further enhance data transmission efficiency, we introduce a semantic-aware vector quantized variational autoencoder (SVQ-VAE) architecture as the local semantic communication model. This architecture optimizes transmission by selectively compressing and quantizing only the most relevant semantic information for the task. Additionally, to address data heterogeneity among vehicles, we propose a hypernetwork-based personalized federated learning (HPFL) scheme. This approach enhances the model’s scalability and generalization by training a hypernetwork at the edge server to generate specific weight parameters for each vehicle’s semantic communication model. Simulation experiments on the CIFAR-10 and BDD100K datasets demonstrate that our proposed federated learning-based semantic-aware communication achieves superior task completion rates, semantic transmission efficiency and transmission delay compared to existing federated semantic communication architectures.

In recent years, semantic communication has garnered significant attention for its potential to address challenges in traditional communication systems. However, in complex communication environments, semantic communication still faces challenges such as semantic information loss, low transmission efficiency, and poor adaptability. This paper proposes a novel Semantic Communication with Adaptive Semantic Reconstruction (SCASR) scheme to enhance transmission efficiency and adaptability in complex communication environments. First, a compression mechanism based on semantic importance is designed to achieve flexible and efficient semantic compression. Then, we develop an adaptive semantic reconstruction network to predict and reconstruct lost semantic information. Finally, we integrate an attention mechanism into the reconstruction network, dynamically adjusting parameter weights based on Signal-to-Noise Ratio (SNR), Semantic Compression Rate (SCR), and Packet Loss Rate (PLR) to improve reconstruction quality and adaptability. To evaluate the efficiency of SCASR, we conduct extensive simulation experiments on semantic segmentation tasks using the Cityscapes dataset. Results demonstrate that SCASR outperforms existing semantic communication and traditional schemes, offering higher Mean Intersection over Union (mIoU), and enhanced Semantic Transmission Benefit (STB).

In the Wireless Arithmetic Label Switching (WALS) architecture and its directional extension, WALS-DA (Directional Antennas), for Mobile Ad Hoc Networks (MANETs), forwarding keys are assigned to nodes or links to enable efficient arithmetic label-based forwarding. However, the inevitable reuse of forwarding keys in WALS introduces anomalous forwarding behaviors and degrades network performance. WALS (nodebased key assignment) and WALS-DA (edge-based key assignment), without addressing specific mitigation strategies. Through extensive simulations using cellular network topologies, we identify distinct conflict propagation patterns between the two architectures. Results demonstrate that internal and external conflicts scale with key duplication rates. However, WALSDAs finer-grained key assignment reduces internal conflicts while significantly amplifying external conflicts under high key reuse. This study comprehensively characterizes the duplicate-label problem in WALS-based routing, providing foundational insights for future improvements in WALSbased MANET forwarding design.

Abstract As a key component of high‐performance switches and routers, the packet forwarding engine (PFE) is mainly responsible for selecting the appropriate output port for tens of thousands of packets within an extremely short time frame. However, the performance of PFE is determined by the selected group membership algorithm. This paper puts forth a hybrid strategy–caching scalar‐pair and vectors routing and forwarding (CSVRF), consisting of virtual output port bitmap caching (VOPBC) and fractional‐ N SVRF to address major multicast forwarding issues such as scalability by using content addressable memory. In CSVRF, a virtual output port bitmap cache is introduced, which includes the most popular combinations of output port bitmap and divides the big scalar‐pair into N sub‐groups to achieve parallel compute and the reusability of less bit‐length prime. The results demonstrate that the memory space and the forwarding latency are effectively reduced compared with previous work. In space efficiency, it only required 10% memory space compared with the original SVRF/fractional‐ N SVRF, decreased 10% memory usage compared with pure VOPBC and nearly improved 1 to 4 orders of magnitude of packet processing time compared with the original SVRF and the fractional‐ N SVRF respectively.

Scalability and performance are major challenges in developing high-performance multicast packet switching technologies in the 5G/6G core networks. We propose a novel scheme called 2-D scalar-matrix and vectors routing and forwarding (2D-SVRF) to address these two issues. Our scheme improves upon commonly used algorithms, Bloom filter (BF) and scalar-pair vectors routing and forwarding (SVRF), which have limitations in space and time efficiency, especially in carrier-grade packet forwarding engines (PFEs) with high-port-density and large membership-capacity. 2D-SVRF transforms a scalar-vector into a scalar-matrix by dividing an n-element group into N-rows (sub-blocks) and dividing an output-port bitmap with$\rho $-elements into M-columns within each sub-block. This enables the reuse of smaller and identical prime keys among different sub-blocks and subscalars. By leveraging this approach, multicast forwarding can be partitioned to exploit parallelism, resulting in reduced memory usage and lower computational complexity. Simulation evaluation confirms that 2D-SVRF outperforms competing algorithms in terms of scalability and efficiency, particularly when optimized with the (M, N) parameters. The 2D-SVRF approach is expected to make the implementation of SVRF feasible in carrier-grade multicast-enabled switches and routers.

Edge caching has emerged as an effective solution to the challenges posed by massive content delivery in the vehicular network. In vehicular networks, vehicles and roadside units (RSUs) can serve as intermediate relays with caching capabilities. However, due to the mobility of vehicles, the topology of the edge network changes frequently, which leads to frequent link interruptions and increases the transmission delay. This paper proposes an adaptive cooperative caching (ACC) strategy to adapt the frequent changes in the vehicular edge network topology and describes an optimization problem to minimize the average transmission delay. Then, the optimization problem is transformed into two sub-optimization problems: multiplechoice knapsack (MCK) problem and multiple minimum-weight dominating set (MMWDS) problem. Finally, two greedy algorithms with low complexity are designed to solve the above two optimization problems and obtain approximate solutions to the optimal caching decision. Simulation results show that ACC can effectively improve the cache hit rate and reduce the average transmission delay and the communication overhead compared with other caching strategies.

This article proposes an innovative unicast/multicast unified, cross-layer, and control/user-plane splitting forwarding method, called wireless arithmetic label switching (WALS), for mobile ad hoc networks (MANETs). The WALS is based on a stateless approach: an arithmetic source-routed label is processed by the source and intermediate nodes without table lookup, causing lower protocol overheads and forwarding latency than the conventional stateless unicast/multicast routing protocols such as the dynamic source routing (DSR) and the differential destination multicast (DDM), respectively. Different from conventional unicasting/multicasting designs demanding distinct routing protocol stacks, the WALS requires a unified protocol stack, avoiding the need to distinguish unicast and multicast frames, thus simplifying the design of MANET devices. Mathematical analysis indicates that the WALS is highly scalable for both the network sizes and the number of multicast groups. Simulation results reveal that WALS effectively performs network scalability and the required overhead for the unicast and multicast capabilities. Additionally, WALS achieves superior to the other three state-of-the-art competitive multicast routing methods, including DVMRP, ODMRP, and MAODV on the performance of the packet processing latency and packet delivery ratio. As a result, the WALS can significantly enable the employment and management of integrated unicast and multicast services for MANETs.

The conventional routing protocol considers several local transmission factors in a single node for the many-to-one packet transmission. These factors lead to rapid energy consumption in some specific nodes, thereby generating energy holes to reduce network lifetime. In this article, a novel energy-balanced power-efficient gathering in sensor information systems (EB-PEGASISs) is proposed to improve energy efficiency and utilization for wireless sensor networks (WSNs). In the original power-efficient gathering in sensor information system (PEGASIS), the protocol constructs a chain-based network with the locally shortest distance rather than the globally optimal network length. To improve this, two construction algorithms are proposed to achieve the shortest network length in the EB-PEGASIS, including centralized formation and distributed construction schemes. In the centralized algorithm, the chain length of each starting node is computed, and the minimum chain length can be subsequently determined in the following packet transmission phase. In order to reduce formation complexity, a distributed method uses the$K$-means clustering algorithm to partition the network into clusters. In particular, it forms a subchain in each cluster and connects each subchain into the final shortest chain. Additionally, to balance the energy consumption among all nodes in the packet transmission phase, Jain’s fairness index for residual battery capacity is designed to minimize the fluctuation of energy consumption among nodes in a network. As a result, not only energy efficiency is achieved with the shortest chain length but also energy utilization is balanced for packet transmission. Ultimately, simulation results validate that the network lifetime of the EB-PEGASIS is about 2.46 times the original PEGASIS and 3.36 times the random projection-polar coordinate-chain (RPC) protocol for WSNs.

In traditional wireless sensor networks (WSNs), packets are mainly transmitted in a multihop routing manner. The multihop transmission, however, leads to a hotspot problem in the sink connectivity area (SCA), and the overall network efficiency is reduced due to the quick battery power exhaustion of nodes in that area. This article proposes a novel balanced routing algorithm with transmission range adjustment (BRATRA) to address the network efficiency problem, including the energy efficiency and utilization issues. First, a balanced routing strategy is designed to deal with the SCA load imbalance problem. With the shortest balanced path, the amounts of forwarding packets for the nodes in the SCA and all the other intralayers become more even. From the perspective of power equilibrium in each routing path, each node then determines its accurate transmission radius according to the derived formula and performs power control to realize the even power utilization between interlayers, thereby prolonging the overall network lifetime. Performance evaluation validates that the proposed BRATRA strategy can achieve efficient power utilization in each intralayer and double the network lifetime as compared to the Dijkstra routing strategy. Additionally, it yields better power utilization fairness among nodes, and on average only 5% of battery power is unused for all network nodes, resulting in a network lifespan ten times larger than that using a conventional strategy.

High-performance multicast-enabled packet forwarding engines (PFEs), as an essential component of high-end switches, use a polynomial-time membership query algorithm to determine which port(s) the data packet should be forwarded. The currently widely used query algorithm is Bloom Filter (BF), which has been proven to have many fatal flaws. Another error-free membership query algorithm includes Scalar-pair Vectors Routing Forwarding (SVRF), Fractional-NScalar-pair Vectors Routing Forwarding (Frac-NSVRF), and the Per-Port Prime Filter Array (P3FA) also have some shortcomings in space and time efficiencies. In this paper, we proposed a hybrid strategy: Divaricate Heterogeneous SVRF (DH-SVRF) scheme, which based on the P3FA and Frac-NSVRF, which randomly divides all member ships intoNgroups, and each group has the same structure and is independent of each other to obtain higher time efficiency and space utilization. Finally, we also discussed the selection of the optimal egress-diversity threshold. Through mathematical modeling and simulation, we validate that the proposed DH-SVRF scheme is superior to the SVRF/Frac-NSVRF and traditional BF in terms of scalability, space utilization, and time efficiency in specific conditions such as appropriate egress-diversity thresholds.

In modern networks, Lawful Interception (LI) is one of the necessary means for security agencies to safeguard national security and prevent crimes. This article intends to explore the dynamic placement problem of intercept access points (IAPs) unique to SDNs, and their derived interception strategies. by selecting the optimal intercept access point, bring the shortest path among the three points-source, destination, and law enforcement agency (LEA). In order to reduce the redundant return intercepted traffic in the network, the operating cost of the LI system must be minimized. We also addressed the performance of the fastest access to the return traffic by the LEA, and the impact on the communication quality of the monitored users. Comparison among the three-interception strategies-source/destination interception model, blocking interception model, and bicast model. the simulation results expressed as a percentage that improved by using the different strategies compared with each other of the total costs of ISP, the performance of LEAs, and affected QoS of monitored users.

High-performance multicast-enabled switches and routers are being constantly developed, which use a polynomial-time group membership query algorithm within the Packet Forwarding Engines (PFEs) to determine whether or not a packet is forwarded through a unique or multiple egress ports. Among these, Bloom filter (BF) and Scalar-pair Vectors Routing and Forwarding (SVRF) are being considered as two representations of the membership query algorithms. However, both approaches suffer from some fatal weaknesses such as space and time inefficiencies, especially for a carrier-grade PFE with high port-density feature. In order to solve these imperfections of SVRF, we propose an improved Fractional-N Scalar-matrix and Vectors Routing and Forwarding (Fractional-N SVRF) scheme based on re-examining the idea of the original SVRF. The Fractional-N SVRF preprocesses a scalar-matrix by dividing an n-element group into N-columns (sub-blocks), thus element' keys belonging to distinct sub-blocks and sub-scalars are allowed to reuse relatively smaller identical prime keys. Based on Fractional-N SVRF, membership queries can be partitioned to leverage task parallelism, therefore better performance is achieved in terms of memory consumption and computational complexity.

Considering that the traffic characteristics of certain applications feature small-data patterns especially in typical IoT control scenarios such as robot control on the downlink. Aggregation data delivery system has good performance in handling multi-source, multi-destination, and massive small-data delivery with characteristics of low-overhead, high-throughput, and ultra-low-latency for a resource-constrained wireless transmission system. In order to rapidly deliver multiple small-data to multiple receivers efficiently, based on P4 switches, we attempt to develop a novel arithmetic aggregation coding scheme based on RNS, which would meet the need to aggregately encode multiple small-data messages, as an indispensable complementary component to the resource-constrained wireless transmission system.

Lawful Interception (LI) is one of the main provisions needed for the Law Enforcement Agencies (LEAs) to intercept a suspect or deal with criminal activities. However, it was easy and expensive to implement in legacy networking due to its centralized administration. Considering this situation, we aim at contributing to the next generation of intelligent lawful interception technology exploiting Software-Defined Network (SDN) technology for reference to deploy intercept access point (IAP) in hybrid SDN where SDN nodes and non-SDN (N-SDN) nodes coexist. Therefore, we put forward three SDN interception models (e.g., T model, ECMP-T model, Fermat-point model) in hybrid SDN. In other words, the algorithms of running three SDN interception models can be viewed as a cost-effective three-points shortest path algorithm with low time and space complexity. Running three SDN interception models, we can thus deploy the best intercept access point reasonably in hybrid SDN, realizing lawful interception of whole lawful interception system.

As a key infrastructure of Industry 4.0, Industrial Internet-of-Things (IIoT) promises the opportunity to build powerful industrial environments by leveraging the growing ubiquity of wired and wireless communication technologies. Designing a data delivery scheme in the future IIoT networks is undoubtedly a challenging task, as it should satisfy several conflicting requirements: massive-scale, data-intensive, and mission-critical, the requirements of which have motivated the desired need for feasible IIoT network architecture. In particular, the traffic characteristics of certain IIoT applications feature small-data patterns especially in typical automation control scenarios such as robot control on the downlink. In order to reduce the huge overhead associated with each individual unicast transmission of the small-data message, we propose a novel “multipoint-to-multipoint” and/or “point-to-multipoint with different contents” communication paradigm-Uni-Multi-Unicast (UMUcast), which is based-on traditional 4G technologies such as evolved Multimedia Broadcast Multicast Service (eMBMS) and Group Communication System Enablers (GCSE), and novel 5G technologies such as Multi-Access Edge Computing (MEC). For the downlink, the UMUcast transmitter can jointly encode multiple-sources' small-data messages into a single chunk at MEC equipment in conjoint with a gNB, where chunk can be one-off transmission to multiple receivers simultaneously through an eMBMS frame, whereas the chunk is decoded into multiple small-data by each individual IIoT devices separately and respectively. The simulation results show that UMUcast has remarkable improvements over conventional point-to-point unicasting in handling multi-source, multi-destination, and massive small-data delivery with characteristics of low-overhead, high-throughput, and ultra-low-latency for future 5G-based IIoT networks.

Due to the advances of VoIP services such as Skype and Line, people are able to make conversation over the Internet with very low cost. However, VoIP is a real-time application and large end-to-end delay may cause poor communication quality. Most existing mechanisms to improve VoIP QoS are based on the traffic classes, but various voice traffic flows may experience different delays due to different end-to-end distances, and hence various number of intermediate hops which cause variation of delay. In this paper, we propose a novel mechanism that assigns different VoIP flows into different queues based on the path selection by SDN. Usually the biggest variable delay in IP voice communication systems is the queuing delay introduced by switches or routers along the path, and the queuing delay is influenced by the link utilization. Thus, we use hop-count and link utilization to determine which queue the incoming VoIP flows should go through. To ease the task of calculating hop-count of flows and link utilization in the intermediate nodes, we use software-defined network (SDN) to perform the task of routing path selection. The simulation results show that our proposed mechanism can improve QoS of VoIP significantly.

For ultra wideband communications, interferences from existing communication systems are unavoidable. In this paper, the effect of interference on impulse radio is analyzed and an interference cancellation scheme based on template design for software defined impulse radio is proposed. Simulation results show that the scheme can suppress the interference effectively. The scheme is applicable to both wideband and narrowband interference cancellation for software defined impulse radio.

For ultra-wideband positioning using impulse radio, intersymbol interference (ISI) is unavoidable, which affects the positioning accuracy. In this paper, a novel ISI cancellation scheme based on wavelet transformation for impulse positioning is proposed. Analog-to-digital conversion of the ultra-wideband signal is not needed, and knowledge of the channel is not required. The desired signal pulse can be distinguished from the interference pulse and precisely located. Instead of using the traditional received pulse, wavelet transformation is applied to generate a new spike signal for detection. A detailed theoretical analysis is presented and closed-form expressions are derived. Simulation results show that the proposed positioning scheme can cancel ISI effectively and achieve significantly lower average positioning error than the original TDOA system without ISI cancellation.

Software-defined networking (SDN) has been considered as a breakthrough progress for the next-generation LAN/WAN technologies. It enables fine-grained flow control that can make networks more customizable and flexible. However, the transition of traditional networking model to SDN architectures poses scalability issues due to the possible flow entry explosion in SDN switches. Typically, flow entries are removed from flow tables in three ways, either at the request of the controller, via the switch flow expiry mechanism, or via the optional switch eviction mechanism. No matter which one the network administrator choose, the invalid flow entries still keep on flow table for a while, thus unsalable due to available space of flow table are exhausted for future requests of continuous flow. In this paper, we propose to address this issue by detecting the disconnect signaling of connection-oriented protocols such as Transmission Control Protocol (TCP) for SDN framework. In particular, we propose to add a specific SDN ruleset with a transparent layer in between the controller and switch, referred to as a TCP FIN detector. TCP FIN detector inspects the FIN bit field from incoming and outgoings traffic; therefore once the transport-layer disconnection can be immediate recognized and no longer rely on timeout. Results of a series of simulations show that our proposed scheme outperforms timeout solutions for significant reduction of both the flow table occupancy and control signal costs.

In this paper, we propose enhanced Reed-Muller (RM) and Polar decoder for SDN-based C-RAN fronthaul. The simulation results show that our proposed algorithm outperforms traditional decoding algorithm in terms of average number of connected user equipment to RRHs, and the feasibility of decoding the RM codes by the Successive Cancellation (SC) decoding algorithm is verified by comparing the performance and decoding time of the RM and Polar codes under the SC and Belief Propagation (BP) iterative algorithm. The simulation results show that the decoding time of SC decoding algorithm is reduced about 98.98% compared with the BP decoding algorithm. For the BP decoding algorithm with excellent decoding performance but long decoding time, this paper proposes an improved BP decoding algorithm based on early terminating iteration criterion of the absolute values difference for the likelihood, which reduces the computational complexity of criterion. The simulation results illustrate that the early-terminating iteration criterion proposed in this paper reduces the computational complexity, thereby reducing the decoding delay and energy consumption effectively, and satisfying the low complexity and energy consumption decoding requirements.

In the past few years, data traffic generated by video applications has become the dominant traffic on the internet due to the rapid development of wireless network and mobile terminal. However, using a single wireless network for video transmission with limited bandwidth is facing great challenges under the increasing video quality requirement. Fortunately, mobile terminal equipped with multiple network interfaces can transmit data over heterogeneous wireless networks concurrently to achieve higher bandwidth. In order to make effective use of heterogeneous access network resources, this paper develops a heuristic flow splitting algorithm based on ACO (Ant Colony Optimization) algorithm. Firstly, a system model with the objective that minimizes the multipath video transmission distortion is proposed under the end-to-end delay constraint. Secondly, to solve the problem based on heuristic ACO, the relevant models such as pheromone model and reliability model are presented, and a heuristic ACO algorithm is proposed. Finally, the proposed algorithm is tested and evaluated in the real-world platform. The evaluation results show that the proposed algorithm performs better than the referenced traditional algorithm in terms of PSNR and end-to-end frame delay.

The continuous growth in traffic volumes on modern Data Center Networks (DCNs) can be classified into either delay-or throughput-sensitive applications. In order to providing quality delivery to such applications, it is important that multipath routing and/or forwarding can be supported in the DCNs. However, some inherent problems of multipath forwarding have not been totally solved by existing solutions. Aiming to balance all these requirements for the multipath DCNs, we propose a novel solution - Code-Oriented eXplicit MultiPath (COXMP) scheme which evenly distributes traffic along multiple paths, resulting in better network throughput, delay, jitter, and resilience. The simulation results show that COXMP outperforms existing solutions and achieves a reasonable tradeoff between scalability and overhead.

Live streaming (a.k.a. Internet Protocol Television (IPTV)) services have been popularly deployed on the Internet. Traditionally, IPTV service provider adopted client-server architecture. However, when the client population grows up to a certain amount, it usually faces the scalability and cost-effective problems. Fortunately, the development of Peer to Peer (P2P) content sharing application has proved that the P2P paradigm is an efficient solution to deliver many kinds of content over the Internet. P2P IPTV services may face the problem that there are more and more Network Address Translator (NAT) users, and peers behind NAT (NATed peer) cannot directly deliver its streaming data to other NATed peers. This situation easily leads to the so-called free rider problem. In this paper, we propose a grouping and scheduling scheme to increase the share rate of NATed peers. By restricting transmission connectivity of those peers with public IP address and properly arrange data chunks delivery, we could allow NATed peer to contribute more data on the overlay network. Simulation results show that proposed scheme can improve the performance in terms of the share rate and video playback quality compared to original NAT traversal mechanism. Besides, the deployment complexity of both P2P IPTV operators and peers, are expected reduction.

Due to the increasing demand of wireless services, mobile access technology has quickly progressed towards the fourth generation Long Term Evolution (LTE) networking paradigm. Hence, providing mobility support in such networks has been a long-standing challenge. Proxy mobile IPv6 (PMIPv6) is a network-based mobility management protocol within LTE, Route optimization (RO) problem in such environments is quite different from today's mobility environments. In this paper, a novel route optimization solution for PMIPv6 over LTE networks based on signaling reduction approach, are proposed. According to the performance evaluation results, we demonstrate that our proposed scheme can accomplish the low latency route optimization as expected.

In this paper, we consider a flexibility and efficiency problem with DLMS automatic reading smart meter system. We introduce a two-tier hierarchy structure with concentrator. Our proposed concentrator model simply extended the power of Device Language Message Specification (DLMS) protocol. The result is then used to make the two-tier hierarchy available. Compared to origin DLMS protocol, our model supports at most 65536 smart meters rather than 256. Our work may be applied to the newest Advanced Metering Infrastructure (AMI) research.

Since the use of wireless devices in the already overcrowded ISM bands had been further growing recently. Realization of wireless communications in TV white space is one of the most urgent research and development issues to accommodate rapidly increasing wireless access. In order to ensure avoidance of interference from secondary users to primary users, adoption of White Space Database (WSDB) is one of the important strategies. In this paper, we introduce the concept of IETF Protocol to Access White Space Database (PAWS), and use it to connect a WSDB and dynamic allocating spectrum resources and monitoring the use of those resources in the IEEE 802.11af (White-Fi) networks. We have implemented the PAWS API and WSDB for spectrum allocation and show that mechanism operations with an experimental IEEE 802af network, which enables White-Fi Access Point (AP) to share the TVWS in a fine geolocation and timescale.

Explicit multicasting protocols such as Differential Destination Multicast (DDM) in MANETs have been retaining advantages of traditional approach while eliminating their shortcomings especially for small-group applications. However, they still have some drawbacks especially in the group size limitation. In this work we discussed a new unified unicast and multicast routing scheme called Arithmetic Labeled EXplicit (ALEX) Multicast Routing based on arithmetic encoding of on-tree node keys and recursive unicast for MANETs. Our scheme constructs the multicast tree by decoding the bitmap of its output ports for next hops in the forwarding path using a common Multicast Channel IDentifier (MCID) and a node-specific key, so that multicast packets can be self-routed to multiple receivers without requiring header modification, and intermediate nodes on the multicast mesh will be stateless. In addition to scaling up the multicast group size, our scheme can reduce the processing complexity, control overhead and delivery latency comparing to the existing works. The simulation results indicated that our proposed scheme achieves a remarkable improvement in scalability while simplifying the deployment and management for a large number of medium-size multicast groups in MANETs.

This paper introduces a new scalable, efficient and stateless source routing scheme to ensure that unified unicast and multicast packets can be delivered in the Data Center Networks (DCNs). This scheme, called Code-Oriented eXplicit multicast (COXcast), is based on unicast and eXplicit multicast (Xcast). It constructs the unicast path and multicast tree by encoding the corresponding output port bitmap of each intermediate node. Using a common identifier and a node-specific key, so packets can be self-routed to multiple receivers without requiring header modification. In addition, intermediate switches/routers on the path/tree can be stateless. Compared to traditional source-based unicasting and explicit-based multicasting schemes, COXcast has lowered the processing cost, protocol overhead and delivery latency, while simplifying the deployment and management of a large number of medium-scale multicast groups, especially when applied to large-scale DCNs.

In this paper, we apply IEEE 802.1Qbu Preemptive Priority Frame Forwarding mechanism to the IEEE 802.3z Gigabit Ethernet networks, and compare its performance with non-frame-preemption queuing schemes for various traffic patterns. A feasible implementation of the proposed solutions is addressed. The FPF effectively reduces the forwarding delay as well as jitter, so as to enhance response time of real-time services in GbE networks. Through simulations, we show that the FPF achieves superior and precise QoS control compared to existing non-preemptive-based priority scheduling schemes.

In this article, we consider a scalability problem associated with software-defined datacenter, of which the unicast/multicast routing states is proven to be NP-complete. We introduce an efficient multiple membership query algorithm, called Scalar-pair Vectors Routing and Forwarding (SVRF), based on the prime theory such as Chinese Remainder Theorem (CRT). Our proposed algorithm simply calculates corresponding output ports of each multicast group by dividing a common scalar-pair with a group-specific key, within pseudo-polynomial time. The result is then used to make a forwarding decision within few cycles through a hardware accelerator. Compared to Bloom filter, our algorithm can achieve remarkable performance in terms of memory consumption, processing time, hardware cost, and 100% delivery accuracy, while applying for a large number of large-scale distinct flows (including unicast and multicast) in a large-scale datacenter networks. Our work may be applied to various research areas of computer science and networking.

This paper presents a novel cross-layer forwarding scheme, called UNified unicast and multiCast LabEling (UNCLE), for mobile ad hoc networks (MANETs). Unlike traditional unicast and multicast forwarding schemes requiring two different protocol stacks, the proposed UNCLE forwarding method requires only one single protocol stack, and thus avoid the need of distinguishing unicast frames from multicast frames. Furthermore, the header of the stateless UNCLE forwarding scheme is designed based on a simple modulo approach, resulting in much lower protocol overheads than the traditional stateless unicast Dynamic Source Routing (DSR) and the Differential Destination Multicast (DDM) schemes. In addition to low forwarding latency the proposed UNCLE is very scalable for various network sizes and the multicast group sizes without table lookup in layers 2 and 3. Therefore, the UNCLE forwarding scheme can facilitate the deployment and management for providing both unicast and multicast services significantly.

A novel label switching architecture for all-optical label switching (AOLS) networks is firstly proposed and experimentally demonstrated. Proposed scheme adopts successful factors of existing architecture such as GMPLS, and to construct a high performance, scalable and manageable IPbased AOLS network. Similar to GMPLS, a particular label based on source routing information is attached to IP packets/burst for fast interconnection purpose rather than an option as source-routing in conventional IP framework, thus the scheme requires neither table lookup nor header replacing in the intermediate node, labeled packets will be quickly forwarded through self-routing, and the only operation in switching nodes is to strip off its part of the label which represents the output port, which eliminates the O/E/O conversion as much as possible. The benefits include simple switching process with low packet delay, higher security, and better scalability on next generation optical Internet.

Circuit Emulation Services (CES) technology has emerged as an option to mitigate traditional TDM circuits supporting legacy applications across managed packet networks. Since Ethernet Passive Optical Network (EPON) is becoming a major technology for pervasive access. The primary benefits of CES over EPON (CESoEPON) are the low cost and simplicity of deployment to support all types of legacy TDM applications across EPONs. Thus, the QoS-guarantee for highly delay-sensitive services on EPONs could be enhanced. This paper investigates a preemptive priority transmission technique that works on MAC and PHY layer of EPONs. The proposed novel scheme effectively reduces the frame queuing delay as well as jitter, so as to enhance precise time synchronization in EPONs. Through simulation experiments, we show that the proposed method achieves superior and precise QoS control compared to existing non-preemptive methods. Finally, we present a general conclusion of the paper.

Client-based Mobile IPv6 (MIPv6) is the most well known mobility management protocol, and the fast emerging proxy-based Mobile IPv6 (PMIPv6) offers an alternative. Some inherent problems such as route optimization in these protocols have not been really solved. Although various proposals tried to tackle the route optimization problem, none of them has achieved a real success. Furthermore, most of them are not comprehensive solutions for coexisting MIPv6/PMIPv6 mobile environment. In this paper, we proposed a novel unified route optimization scheme - Traffic Driven Pseudo Binding Update (TDPBU) to accommodate various mobility management issues. We evaluated our proposed scheme through simulations, and numerical results show that TDPBU can significantly improve the overall performance of mobility management protocols. Index Terms—Route Optimization, Mobile IPv6 (MIPv6), Proxy Mobile IPv6 (PMIPv6), Traffic-Driven Pseudo Binding Update (TDPBU), Network Mobility (NEMO).

Recently, the Orthogonal Frequency Division Multiplexing Access (OFDM/OFDMA) based wireless transmission technology has been widely accepted by consumers. Frame Check Sequence (FCS) scheme was employed to enhance the reliability of OFDM/OFDMA systems. Since the padding overhead cannot be effectively avoided in OFDM/OFDMA when MAC frames are encapsulated. We propose a novel CRC based error correction scheme by utilizing the frame padding to carry extra segmented FCS information as much as possible; compared with legacy FCS scheme, our approach obtains a significant improvement in error detection and correction upon the first retransmission (2ndtransmission). In addition, we demonstrate a significant performance improvement based on the mathematic analysis.

This paper gives a theoretical approach to modeling and simulating the Grade of Service (GoS) of Voice over Peer-to-Peer Session Initiation Protocol system which is created based on various teletraffic parameters. VoP2P features a particular service characteristic due to its different GoS models originated from circuit switched telephone networks. Especially, most voice session in VoP2P is indirectly connected because peer-nodes usually locate behind NATs. This situation forces peer-node to select one or more relay-node for establishing sessions. However, the relay-node is a constrained resource because every relay-node can only support very limited relay services in VoP2P network. There are two strategies, the S2RS (Staged Single-Relay Strategy) and MRS (Multi-Relay Strategy), to solve the relay-node issue. We adopt three new parameters in VoP2P call-loss models, the first is callee-attendance rate, which is due to the characteristic of destination peer-nodes with a lower attendance probability; the second is call-blocking rate, which is a traditional definition just because the relay-node reaches the limitation of resource; the third is handoff-dropping rate (aka handoff-loss rate), which is caused by the relay-node being removed frequently. The simulation results provide useful reference in the study of teletraffic of VoP2P system.