Showing papers on "Equal-cost multi-path routing published in 2023"

BRATRA: Balanced Routing Algorithm With Transmission Range Adjustment for Energy Efficiency and Utilization Balance in WSNs

Abstract: 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.

EGMPIP: Enhanced Geographic Multipath Routing using Gossip-Based Direct Neighbor Discovery Algorithm in Wireless Sensor Networks

Abstract: Many paths between the source and sink nodes may be detected using multi-path routing in WSNs. The reliability, energy efficiency, and other benefits of data transmission may be increased by using many channels. The topic of multi-path routing has been the subject of several academic studies. These multi-path routing protocols, however, are ineffective because of the time and energy needed to build several channels. The elimination of bottlenecks and delays in data transmission is made possible by multipath routing in WSNs. Network QoS (Quality of Service), load balancing, and communication dependability may all benefit from multipath routing systems. To identify multipath routing in WSN, we suggested the Enhanced Geographic multipath (EGMPIP) architecture. The proposed framework first constructs the base station routing algorithm by computing the Neighbor node discovery (NND) function in the network using the G-ND. Each node in the network may make use of multipath routing thanks to the network-wide routing mechanism. In the end, simulation data are shown to validate the suggested technique, and the findings demonstrate that the routing strategy described in this work is superior to past methods.

Disjoint Paths Construction and Fault-tolerant Routing in BCube of Data Center Networks

Abstract: BCube is a promising structure of data center network, as it can significantly improve the performance of typical applications. With the expansion of network scale and increasement of complexity, reliability and stability of networks have become more essential. In this paper, we study the fault-tolerant routings in BCube. Firstly, we design a fault-tolerant routing algorithm based on node disjoint multi-paths. The proposed multi-path routing has stronger fault tolerance, since each path has no other common nodes except the source node and the destination node. Secondly, we investigate an effective fault-tolerant routing based on routing capabilities algorithm for BCube. The proposed algorithm has higher fault tolerance and success rate of finding feasible routes, since it does not limit the faults number. Thirdly, we present an adaptive path finding algorithm for establishing virtual links between any two nodes in BCube, which can shorten the diameter of BCube. Extensive simulation results show that the proposed routing scheme outperforms the existing popular algorithms. Compared with the state-of-the-art fault-tolerant routing algorithms, the proposed algorithm has a 21.5% to 25.3% improvement on both throughput and packet arrival rate. Meanwhile, it reduces the average latency of 18.6% and the maximum latency of 23.7% in networks.

SDN routing strategy based on genetic algorithm and particle swarm optimization under SFC background

Abstract: To solve the problem of low routing efficiency and limited link utilization when Service Function Chain (SFC) deployment adopts the traditional shortest path algorithm in the face of large-scale network topology due to the expansion of the path search scope and only considering the shortest path each time, this paper proposes a routing strategy based on meta-heuristic algorithm to achieve the optimization of SFC routing. Firstly, the inertia weights in the original PSO algorithm are dynamically processed to adapt to the dynamic characteristics of Software Defined Networking (SDN) network topology and improve the optimization ability and convergence speed of the original algorithm. Secondly, the crossover and mutation of genetic algorithm are introduced to improve the ability of the algorithm to find the optimal path. Simulation results show that compared with the traditional k-shortest path algorithm, the proposed method can effectively improve link utilization during routing, reduce the routing time of large-scale network topology, and improve the SFC routing efficiency.

Faster goal-oriented shortest path search for bulk and incremental detailed routing

Abstract: We develop new algorithmic techniques for VLSI detailed routing. First, we improve the goal-oriented version of Dijkstra's algorithm to find shortest paths in huge incomplete grid graphs with edge costs depending on the direction and the layer, and possibly on rectangular regions. We devise estimates of the distance to the targets that offer better trade-offs between running time and quality than previously known methods, leading to an overall speed-up. Second, we combine the advantages of the two classical detailed routing approaches - global shortest path search and track assignment with local corrections - by treating input wires (such as the output of track assignment) as reservations that can be used at a discount by the respective net. We show how to implement this new approach efficiently.

Intelligent Routing in Directional Ad Hoc Networks Through Predictive Directional Heat Map from Spatio-Temporal Deep Learning

Abstract: By applying a simple shortest/minimum-cost routing algorithm, the mobile ad-hoc network (MANET) with heavy data transmissions may be easily congested if multiple routing paths meet at the same relay node. A path may be unable to provide high throughput since some of its path nodes are helping other paths to forward the heavy traffic. Therefore, those busy nodes should be avoided when a new path is to be established. The task of optimal path seeking becomes more challenging when a MANET is equipped with directional antennas that may cause directional interference with neighboring receivers. The motivation of our research is to build an intelligent proactive routing scheme for MANETs with directional antennas. Our directional routing protocol considers not only the global traffic distribution in different areas of the MANET, but also the properties of directional antennas. It uses spatio-temporal deep learning algorithm to predict the next-time snapshot of directional heat map (DHM), which shows the traffic density distribution in each network location as well as the coverage of each directional antenna. Such a DHM will be used to identify the optimal path that can avoid congested areas as well as the interference from all neighboring directional links. Furthermore, an optimization algorithm is designed to perform optimal path selection. It is able to automatically split a single path into multiple ones that later on get converged again into one path, if the path needs to go around a congested area. Therefore, our routing scheme achieves better quality-of-service (QoS) performance than traditional routing mechanisms such as AODV and OLSR.

Simultaneous Connections Routing in Wavelength–Space–Wavelength Elastic Optical Switches

Abstract: In this paper, we investigate the three-stage, wavelength–space–wavelength switching fabric architecture for nodes in elastic optical networks. In general, this switching fabric has r input and output switches with wavelength-converting capabilities and one center-stage space switch that does not change the spectrum used by a connection. This architecture is most commonly denoted by the WSW1 (r, n, k) switching network. We focus on this switching fabric serving simultaneous connection routing. Such routing takes place mostly in synchronous packet networks, where packets for switching arrive at the inputs of a switching network at the same time. Until now, only switching fabrics with up to three inputs and outputs have been extensively investigated. Routing in switching fabrics of greater capacity is estimated based on routing in switches with two or three inputs and outputs. We now improve the results for the switching fabrics with four inputs and outputs and use these results to estimate routing in the switching fabric with an arbitrary number of inputs and outputs. We propose six routing algorithms based on matrix decomposition for simultaneous connection routing. For the proposed routing algorithms, we derive criteria under which they always succeed. The proposed routing algorithms allow the construction of nonblocking switching fabrics with a lower number of wavelength converters and the reduction of the overall switching fabric cost.

An effective routing strategy using congestion signaling for various types of communication networks

Abstract: Finding the shortest paths for packets in communication networks is one of the vital engineering challenges. Recently, a routing strategy using gravitational centrality has been proposed to find efficient transmitting routes for packets to their destinations. This routing strategy successfully mitigates the congestion of packets in the networks and effectively transmits many packets to their destinations by using gravitational centrality. However, this routing strategy is difficult to transmit the packets to their destinations if large volumes of packets flow in the communication networks because fixed costs are used to determine the shortest paths for every source-destination pair. To overcome these problems, we have already proposed a routing strategy using congestion signals. This routing strategy further mitigates the congestion of packets compared to conventional routing strategies such as the routing strategy with gravitational centrality. In this study, we comprehensively evaluate the routing strategy with the congestion signals if different types of centralities are incorporated into the costs of links and various topologies are applied to the communication network models. Numerical experiments illustrate that our routing strategy using the congestion signals mitigates the congestion of packets even if other types of centralities are incorporated. In addition, our proposed routing strategy shows effective transmitting performance for the various topologies of networks.

JRouter: A Multi-Terminal Hierarchical Length-Matching Router under Planar Manhattan Routing Model for RSFQ Circuits

Abstract: Superconducting rapid single-flux-quantum (RSFQ) logic has shown great potential for high-energy-efficient computing systems. To ensure correct operations at ultra-high frequencies, it is necessary to incorporate length-matching constraints into the routing problem. Existing routing algorithms, however, can only address 2-pin connections or support the conventional horizontal/vertical routing model, which substantially limits the optimization space for routing solutions. This paper presents JRouter, an RSFQ router that considers the two-layer planar Manhattan routing model while simultaneously coping with splitter (SPL) placement and length-matching multi-terminal routing. JRouter contains a track-assignment-based initial routing that minimizes the initial routing width while avoiding conflicts in the horizontal constraint graph. Moreover, JRouter implements an SPL-tree-based hierarchical routing with an iterative maximum-flow-based formulation to insert the detours for multi-terminal routing. A routing region extension algorithm is also developed to insert the detours for unsatisfied connections. According to the experimental results, JRouter achieves an average routing width reduction of 35.71% and 22.46% on a 16-bit RSFQ Sklansky adder compared to Kito's and Kou's routing algorithms. For randomly generated benchmarks, JRouter reduces the routing width by an average of 38.77%, 38.20%, 21.65%, and 7.01% compared to Kito's, Kou's, and two of Yan's routing algorithms, respectively, while maintaining reasonable runtime.

An Intersection-Based QoS Routing for Vehicular Ad Hoc Networks With Reinforcement Learning

Abstract: Vehicular ad hoc networks (VANETs) have the characteristics of high mobility, frequently changing topology and uneven distribution, which made it a challenge to design an efficient and robust routing protocol with low latency and high packet delivery rate. Currently, intersection-based routing method and full-path based routing method are two popular solutions for the packet routing in VANETs. Although the intersection-based routing method has better real-time performance, it has the problem of local optimization, making the routing results not global optimal. Although the full-path based method can obtain the global optimal solution, it is weak in dealing with the dynamically changing topological network. Aiming at solving the above problems, this paper designs an intersection-based QoS routing (IQRRL) algorithm, which mainly includes two crutial steps: the next intersection selection and the next hop vehicle selection. In the selection of the next intersection, this paper uses an improved intersection-based routing protocol. In addition to considering connectivity and delay, IQRRL also considers the communication quality from the neighbor’s road to the destination node while evaluating the quality of the neighbor’s road, which minimizes the problem of local optimization. When the next intersection is determined, a road is then determined, and then the next hop vehicle within the road should be chosen to relay the packet forward. In the next-hop vehicle selection step, this paper adopts multi-hop evaluation technology based on reinforcement learning. In addition to using “greedy decision-making” to select the next-hop vehicle, it also comprehensively evaluates whether the next-hop vehicle is still optimal in the future, so that the stability and reliability of data forwarding are improved and local optimal problems are avoided. Besides, this article uses a simulation system to compare IQRRL with other routing algorithms. The result reveals that IQRRL outperforms in terms of packet delivery ratio and transmission delay.

Hop-Constrained Oblivious Routing

Abstract: We prove the existence of an oblivious routing scheme that is -competitive in terms of , thus resolving a well-known question in oblivious routing. Concretely, consider an undirected network and a set of packets each with its own source and destination. The objective is to choose a path for each packet, from its source to its destination, so as to minimize , defined as follows: The dilation is the maximum path hop length, and the congestion is the maximum number of paths that include any single edge. The routing scheme obliviously and randomly selects a path for each packet independent of (the existence of) the other packets. Despite this obliviousness, the selected paths have within a factor of the best possible value. More precisely, for any integer hop constraint , this oblivious routing scheme selects paths of length at most and is -competitive in terms of congestion in comparison to the best possible congestion achievable via paths of length at most hops. These paths can be sampled in polynomial time. This result can be viewed as an analogue of the celebrated oblivious routing results of Räcke [Proceedings of the 43rd Annual IEEE Symposium on Foundations of Computer Science, 2002; Proceedings of the 40th Annual ACM Symposium on Theory of Computing, 2008], which are -competitive in terms of congestion but are not competitive in terms of dilation.

A routing method with adaptively adjusting memory information based on local routing history

Abstract: Finding the shortest paths for packets from sources to destinations in packet-switched communication networks is an inevitable problem in building a future high-speed information society. A routing method with memory information has already been proposed to alleviate the congestion of large volumes of packet flow. This routing method shows a high transmission completion rate even for large volumes of packet flows in communication networks with scale-free properties. However, the method exhibits poor performance for networks with local triangular connections and long distances between nodes. To overcome these problems, in this study, we first enhanced the routing performance of the conventional communication network models by using the betweenness centrality of nodes, which is one of the network centralities that measures the number of shortest paths that pass through each node in the networks. Subsequently, we adaptively changed the transmitting paths of packets by using only local information. Numerical simulations indicated that our routing method performs successfully for various topologies of communication networks by avoiding the congested node, and effectively using the memory information.

Efficient Packet Flow Path Allocation Using Node Proclivity Tracing Algorithm

Abstract: In the mobile ad hoc network, the mobile nodes activities are different; if the node activity is good, then it performs normal routing process, otherwise it performs abnormal routing. Such abnormal routing node is called as omission node. This node does not transmit and receive data packet at the given specific time slot. Data packets are not reached to destination; it decreases the packet delivery ratio, increases the energy consumption, and decreases the network overall performance. Detection of such nodes is difficult. So the proposed technique, efficient packet flow path allocation (EPF), is used to establish the optimized route between source and destination. EPF analyzes the packet forwarding behavior of each node and packet size of each node transmission. The node proclivity tracing algorithm is used to measure the every node’s characteristics in the particular routing path and capture the omission attacker node in the path. This improves the detection efficiency and minimizes the overall energy consumption of the network.

A Global Measurement of Routing Loops on the Internet

Abstract: Persistent routing loops on the Internet are a common misconfiguration that can lead to packet loss, reliability issues, and can even exacerbate denial of service attacks. Unfortunately, obtaining a global view of routing loops is difficult. Distributed traceroute datasets from many vantage points can be used to find instances of routing loops, but they are typically sparse in the number of destinations they probe. In this paper, we perform high-TTL traceroutes to the entire IPv4 Internet from a vantage point in order to enumerate routing loops and validate our results from a different vantage point. Our datasets contain traceroutes to two orders of magnitude more destinations than prior approaches that traceroute one IP per /24. Our results reveal over 24 million IP addresses with persistent routing loops on path, or approximately 0.6% of the IPv4 address space. We analyze the root causes of these loops and uncover new types of them that were unknown before. We also shed new light on their potential impact on the Internet. We find over 320k /24 subnets with at least one routing loop present. In contrast, sending traceroutes only to the .1 address in each /24 (as prior approaches have done) finds only 26.5% of these looping subnets. Our findings complement prior, more distributed approaches by providing a more complete view of routing loops in the Internet. To further assist in future work, we made our data publicly available.

Implementation and Performance Evaluation of Load Balanced Routing in SDN based Fat Tree Data Center

Abstract: As the number of data intensive and distributed applications increase, data centers are highly utilized for their storage, processing and accessing. These applications cause throughput sensitive incast traffic in the data center. Traditional shortest path routing algorithms cause traffic hotspots in the shortest path links and lead to congestion. Therefore, load balanced routing strategies need to be employed to spread the traffic across multiple paths. This work employs the idea of multi path routing to achieve load balancing in SDN based Fat tree Data center. It implements Equal Cost Multi Path routing algorithm on Fat tree Data Center Network in Ryu SDN controller and evaluates its load balancing performance against traditional Shortest Path Routing algorithm under different data center benchmark traffic scenarios. We have conducted an exhaustive study about the load balancing effect of ECMP on Ryu based SDN Fat tree data center and found that ECMP increases Average network throughput by 68% and Average Link utilization by 60%. Also packet drop is decreased by 44% with ECMP.

Pin Access-Oriented Concurrent Detailed Routing

Abstract: Due to continuously shrunk feature sizes and increased design complexity, the difficulty in pin access becomes one of the most critical challenges in large-scale full-chip routing. State-of-the-art pin access-aware detailed routing techniques suffer from either the ordering problem of the sequential routing scheme or the inflexibility of pre-determining an access point for each pin. Some other routing-related studies create pin extensions with Metal-2 metal segments to optimize pin accessibility; however, this strategy may not be practical without considering the contemporary routing flow. This paper presents a pin access-oriented concurrent detailed routing approach conducted after the track assignment stage. The core detailed routing engine is based on an integer linear programming (ILP) formulation, which has lower complexity and can flexibly tackle multi-pin nets compared to an existing formulation. Besides, to maximize the free routing resource and to keep the problem size tractable, a pre-processing flow trimming redundant metals and inserting assistant metals is developed. The experimental results show that compared to a state-of-the-art academic router, the proposed concurrent scheme can effectively derive good results with fewer design rule violations and less runtime.

Improving Quality of Service using Multipath Routing Protocol for Delay Sensitive Applications of Internet of Things in Wireless Sensor Networks

Abstract: Objectives: To increase the data transmission between the nodes and decrease the latency in data transmission between the nodes than the traditional routing methods. Methods: A novel methodology is being proposed to increase the success rate of real-time transmission by competitively utilizing high-quality links included in different paths in real-time multi-path routing. That is, if a packet that arrives first in one path is copied and delivered to another path immediately, each path competitively delivers the packet in realtime, which has the effect of delivering the packet through a virtual real-time optimal path composed only of high-quality links can be obtained through this, the proposed method can provide a higher success rate for real-time transmission than the existing methods in an environment where link quality is variable. To achieve this goal, the proposed method consists of 1) multi-path configuration method, 2) bridge node selection method, and 3) contention realtime transmission method. Findings: Performance evaluation is performed by comparing and analyzing the experimental results of Equal-Cost Multi-Path Routing (ECMP) and PMMR (Partitioning Multi-constrained Multipath Routing) among the existing multi-path methods and various conditions of the proposed method. The proposed method obtains three results according to the latency (0, 0.05, and 0.1) of the bridge node, and independent multi-path transmission allows each path to follow a single-path routing method. Novelty : The performance of data transmission between nodes is increased and reduced the latency time by the Proposed Contention Transmission Routing Algorithm (PCTRA) when compared to ECMP and PMMR. Keywords: Wireless Sensor Networks; Internet of Things; Multipath Routing Protocol; Real Time Routing; High Speed Data Transmission

A lightweight deployment of TD routing based on SD-WANs

Abstract: Multipath routing conforms to the evolution principle of network development and is a trend of routing architectures. It can not only meet the needs but also enhance the performance and security of a network. However, deploying multipath routing further increases the scale of the forwarding information base (FIB) and the cost of forwarding devices. Therefore, to realize the lightweight deployment of multipath routing with a distributed architecture, this paper takes two-dimensional routing (TD routing) as an example to provide a solution. We propose a distributed storage mechanism of TD routing in combination with SRv6 (TDSR) and the corresponding SRv6 header (SRH) compression (CARD) method. The main methods are as follows: Inspired by a software-defined wide area network (SD-WAN), this paper introduces segment routing (SR) in the data plane, which can disperse TD-FIBs in different ingress nodes. The ingress routers push path information into the stack, and the intermediate routers forward the packets according to the SRH. Second, for the bandwidth waste of the SRH, compression is attempted by comparing the difference between the the shortest path first (SPF) path and the SRv6 path. Only a few hops in the TD path that are different from those in the one-dimensional (OD) path are kept. Finally, we sort out several typical application scenes of multipath routing and discuss several simplification algorithms. The experimental results show that the TDSR can reduce TD entries by 69%, and the average compression rate of CARD can reach 70%. In addition, CARD can be combined with existing methods to improve their effect.

Simultaneous escape routing based on multi-commodity flow

Abstract: As size of pin arrays increases significantly, Printed Circuit Board routing becomes an arduous and challenging problem. Traditional manual routing might cost a lot of time. Simultaneous escape routing is a routing problem based on multiple pin arrays, and it’s an important stage of PCB routing. In this paper, we propose a novel algorithm to solve the SER problem based on Multi-Commodity Flow. Experimental results show that our method can obtain shorter wire length and use less boundary resources than other methods.

A Fast FPGA Connection Router Using Pre-routing Based Parallel Local Routing Algorithm

Abstract: Routing is one of the most time-consuming steps in the FPGA design process. Even if unceasing efforts have been made to accelerate FPGA routing, the existing work seldom pays attention to the underlying FPGA connection router. In this paper, we present a fast FPGA connection router called PRoute which implements a novel pre-routing based parallel local routing algorithm. Basically, PRoute pre-computes the potential routing solutions for various connection patterns on FPGAs, which can be directly used in the later practical routing. On the whole, PRoute is composed of A-star maze expansion and parallel local search. In the first part, PRoute gradually expands the maze wavefront towards the lowest-cost node to search for the target sink. For a wire-type node, PRoute invokes a fast parallel local search instead taking advantage of the pre-routing results, and hence the time-expensive maze expansion can be reduced. Particularly, it allows PRoute to call one another between A-star maze expansion and parallel local search. This enables the runtime efficiency of PRoute while ensuring its global search ability. In addition, we put forward an engineering improvement to further speed up PRoute by avoiding the exploration of block output pins. To our best knowledge, this work is the first to apply the idea of pre-routing for FPGAs. Experimental results show that PRoute achieves speedups of 1.8×, 2.4×, 3.2×, 4.1× and 5.1× with 1, 4, 8, 16 and 32 threads relative to the baseline VPR’s connection router respectively, without degrading the quality of results.

Power: Multi-Capatibility Adaptive Routing for Network-an-Chips

Abstract: Effective adaptive routing is essential for optimal network-on-chips (NoCs) performance, especially for complex and diverse traffic patterns of emerging applications on many-core architectures. However, adaptive routing still encounters significant challenges. It is well known that adaptive routing should have maximizing routing adaptiveness, but it breaks the uniform traffic pattern, reduces the network performance, and can be endpoint congestion in the presence of non-uniform traffic patterns (such as hotspot traffic patterns). We found that most existing adaptive routing fails to be compatible with multiple traffic patterns and network congestion at the same time. To address this limitation, we propose the Power _ a new adaptive routing algorithm that has a strengthen routing adaptiveness and backpressure capability. The Power algorithm can effectively isolate endpoint congestion by avoiding the path of packets that are about to reach the destination to reduce congestion spreading and can achieve dynamic load-balancing by regulating routing adaptiveness when meeting heavy uniform traffic. We conduct extensive experiments against Footprint routing algorithms to evaluate our routing algorithm, and our simulation results show that our design can be improved by up to 36.15% under heavy synthetic traffic patterns.

Routing Strategies for Isochronal-Evolution Random Matching Network

Abstract: In order to abstract away a network model from some real-world networks, such as navigation satellite networks and mobile call networks, we proposed an Isochronal-Evolution Random Matching Network (IERMN) model. An IERMN is a dynamic network that evolves isochronally and has a collection of edges that are pairwise disjoint at any point in time. We then investigated the traffic dynamics in IERMNs whose main research topic is packet transmission. When a vertex of an IERMN plans a path for a packet, it is permitted to delay the sending of the packet to make the path shorter. We designed a routing decision-making algorithm for vertices based on replanning. Since the IERMN has a specific topology, we developed two suitable routing strategies: the Least Delay Path with Minimum Hop (LDPMH) routing strategy and the Least Hop Path with Minimum Delay (LHPMD) routing strategy. An LDPMH is planned by a binary search tree and an LHPMD is planned by an ordered tree. The simulation results show that the LHPMD routing strategy outperformed the LDPMH routing strategy in terms of the critical packet generation rate, number of delivered packets, packet delivery ratio, and average posterior path lengths.

Sparse Semi-Oblivious Routing: Few Random Paths Suffice

Abstract: The packet routing problem asks to select routing paths that minimize the maximum edge congestion for a set of packets specified by source-destination vertex pairs. We revisit a semi-oblivious approach to this problem: each source-destination pair is assigned a small set of well-chosen predefined paths before the demand is revealed, while the sending rates along the paths can be optimally adapted to the demand. This approach has been considered in practice in network traffic engineering due to its superior robustness and performance as compared to both oblivious routing and traditional traffic engineering approaches. We show the existence of sparse semi-oblivious routings: only O(log n) paths are selected between each pair of vertices. The routing is (poly log n)-competitive for all demands against the offline-optimal congestion objective, even on worst-case graphs. Even for the well-studied case of hypercubes, no such result was known: our deterministic and oblivious selection of O(log n) paths is the first simple construction of a deterministic oblivious structure that nearoptimally assigns source-destination pairs to few routes. Prior work shows that a deterministic selection of a single path in a hypercube yields unacceptable performance; our results contrast the current solely-negative landscape of results for semi-oblivious routing. We give the sparsity-competitiveness trade-off for lower sparsities and nearly match it with a lower bound. Our construction is extremely simple: Sample the few paths from any competitive oblivious routing. Indeed, this natural construction was used in traffic engineering as an unproven heuristic. We give a satisfactory theoretical justification for their empirical effectiveness: the competitiveness of the construction improves exponentially with the number of paths. In other words, semi-oblivious routing benefits from the power of random choices. Finally, when combined with the recent hop-constrained oblivious routing, we also obtain sparse and competitive structures for the completion-time objective.

The Smart Performance Development of Geographic Routing in a Reliable Communication

Abstract: Geographic routing is a routing method used in communication networks that is effective, dependable, and resilient. It is based on the actual locations of the network nodes. The source and destination nodes' geographic coordinates are used to determine the route, taking into consideration any obstacles or other nodes along the path. Geographic routing is especially useful in sensor networks where the nodes have limited capabilities. Geographic routing works by using the geographic coordinates of the nodes to select the shortest and most reliable path. The route is then determined by taking into account any obstacles or other nodes along the path. This ensures that the route is reliable and secure. The main advantages of geographic routing are its scalability, robustness, and reliability. The geographic routing is reliable. It is able to maintain a reliable and secure connection even in the presence of environmental changes. This is because the route is determined based on the geographic coordinates of the nodes, which are not affected by the environment. The geographic routing is an efficient, reliable and robust routing technique used in communication networks. It is based on the actual locations of the network nodes and can keep a safe and stable connection even when there are barriers or other nodes in the way. Additionally, it is very trustworthy, robust, and scalable.