Showing papers on "Static routing published in 2021"

The vehicle routing problem with cross-docking and resource constraints

Abstract: In this paper, we propose an extension of the vehicle routing problem with cross-docking that takes into account resource constraints at the cross-dock. These constraints limit the number of docks that can be used simultaneously. To solve this new problem, we adapt a recently proposed matheuristic based on large neighborhood search. In particular, we focus on the feasibility tests for insertions and compare heuristics and constraint programming strategies. Finally, computational experiments on instances adapted from the vehicle routing problem with cross-docking are reported. They give insights on the impact of a limited cross-dock capacity on the routing cost.

On the quality requirements of demand prediction for dynamic public transport

Abstract: As Public Transport (PT) becomes more dynamic and demand-responsive, it increasingly depends on predictions of transport demand. But how accurate need such predictions be for effective PT operation? We address this question through an experimental case study of PT trips in Metropolitan Copenhagen, Denmark, which we conduct independently of any specific prediction models. First, we simulate errors in demand prediction through unbiased noise distributions that vary considerably in shape. Using the noisy predictions, we then simulate and optimize demand-responsive PT fleets via a linear programming formulation and measure their performance. Our results suggest that the optimized performance is mainly affected by the skew of the noise distribution and the presence of infrequently large prediction errors. In particular, the optimized performance can improve under non-Gaussian vs. Gaussian noise. We also find that dynamic routing could reduce trip time by at least 23% vs. static routing. This reduction is estimated at 809,000 €/year in terms of Value of Travel Time Savings for the case study.

Segment Routing Centralized BGP Egress Peer Engineering

Abstract: Segment Routing (SR) leverages source routing. A node steers a packet through a controlled set of instructions, called segments, by prepending the packet with an SR header. A segment can represent any instruction topological or service-based. SR allows to enforce a flow through any topological path while maintaining per-flow state only at the ingress node of the SR domain. The Segment Routing architecture can be directly applied to the MPLS dataplane with no change on the forwarding plane. It requires a minor extension to the existing link- state routing protocols. This document illustrates the application of Segment Routing to solve the BGP Egress Peer Engineering (BGP-EPE) requirement. The SR-based BGP-EPE solution allows a centralized (Software Defined Network, SDN) controller to program any egress peer policy at ingress border routers or at hosts within the domain.

Reliability-aware Scheduling and Routing for Messages in Time-sensitive Networking

Abstract: Time-sensitive Networking (TSN) on Ethernet is a promising communication technology in the automotive and industrial automation industries due to its real-time and high-bandwidth communication capabilities. Time-triggered scheduling and static routing are often adopted in these areas due to high requirements on predictability for safety-critical applications. Deadline-constrained routing and scheduling in TSN have been studied extensively in past research. However, scheduling and routing with reliability requirements in the context of transient faults are not yet studied. In this work, we propose an Satisfiability Modulo Theory-based technique to perform scheduling and routing that takes both reliability constraints and end-to-end deadline constraints into consideration. Heuristics have been applied to improve the scalability of the solution. Extensive experiments have been conducted to demonstrate the efficiency of our proposed technique.

Hybrid energy efficient static routing protocol for homogeneous and heterogeneous large scale WSN

Abstract: Wireless sensor networks consist of a large number of nodes deployed randomly in an area of interest. Theses nodes have sensing, computation, and wireless communications capabilities. In another hand nodes have energy constraints since they are equipped by non-rechargeable batteries. To handle this issue, routing protocols consist of designing the network in order to collect and transmit data with less energy consumption. In this paper we presented a new Hybrid Energy Efficient Static routing protocol (HEESR), combining between clustering and multi-hop routing techniques. HEESR is dividing the network into several levels. For each round, it creates clusters, route the collected data through gateways called Independent Nodes, elected using a new dynamic approach and introduces Dormant nodes. Finally, the proposed HEESR have improved network’s life time, throughput and other compared metrics, in both homogeneous and heterogeneous networks, and prolonged network’s stability zone up to 98.4% compared to LEACH, 98% compared to DEEC and up to 40.5% compared to SMR.

A multiple ant colony system with random variable neighborhood descent for the dynamic vehicle routing problem with time windows

Abstract: This paper proposes a framework to solve the dynamic vehicle routing problem with time windows. This problem involves determining the minimum cost routes of a homogeneous fleet for meeting the demand for a set of customers within time windows. In addition, new customers can be assigned to vehicles during the execution of the routes. A framework is based on two phases: a priori where the routes are obtained for the known customers using static routing, and a posteriori where routes are re-optimized repeatedly during the planning horizon either continuously or periodically. The framework was validated using seven algorithm variants based on insertion heuristic, ant colony optimization, variable neighborhood descent, and random variable neighborhood descent, which were adapted to solve a posteriori phase. The best algorithm is a hybrid version that combines an improved version of the multiple ant colony systems with a random variable neighborhood descent. Computational results show that most of the algorithms are competitive regarding the state of the art with the best results in the objective of minimizing the number of unserved customers.

Juniper and Cisco routing policy and protocols for multivendor IP networks

Abstract: From the Publisher: Obtain a clear understanding of how routing information and traffic flows on a multivendor network Routing policies for networks are often complex and not well understood. Many books detail the operation of routing protocols such as OSPF or BGP, but none place the protocols in the context of routing policies and the real world of ISP peering and customer relationships. Once realistic expectations of packet routing behavior are added to the basic routing protocols, routing policies are unavoidable. Fortunately, Walter Goralski sheds some much-needed light on this intricate protocol-policy relationship by offering two important benefits where other routing books fall short. Goralski covers both Juniper and Cisco, and touches on other vendor implementations. Next, he focuses on real routing policy situations–the way routing domains actually work–instead of just detailing the protocol anatomy. Real-world multivendor configuration examples make this a hands-on guide for the network engineer or administrator who needs to optimize network traffic flows. Topics covered include: Addressing and routing Subnets and supernets ISP peering and routing policies Cisco and Juniper Networks router configuration Routing Information Protocol (RIP) Configuring RIP, OSPF, IS-IS, and BGP Routing policies for all networking situations Author Biography: Walter J. Goralski is an instructor and course developer at Juniper Networks, the number-two vendor of network routing products. Goralski has more than 35 years of experience in data communications, including 14 years at AT&T. He has written seven books on networking topics, the most recent one on optical networking.

EEHRP: Energy Efficient Hybrid Routing Protocol for Wireless Sensor Networks

Abstract: With Multi-Objective Optimization (MOO) mechanisms, many practical scenarios are imitated in Wireless Sensor Networks (WSNs). In MOO numerous desirable conflicting or non-conflicting objectives contend with one another and the decision has to be done among multiple available solutions. Based on the type of situation, Programme, and issue to be solved, the MOO problem has varied solutions. The solution chosen is a tradeoff solution on several occasions. In WSN, it is possible to identify MOO issues and associated solutions based on network architecture, node deployment, MAC strategies, routing, data aggregation, node mobility, etc. In this context, the paper proposes mobility aware, competent; delay tolerant Energy Efficient Hybrid Routing Protocol (EEHRP). Optimizing several metrics to pick the best route from the source to the target node is the cornerstone of the EEHRP. Multi-Objective optimization from optimization theory is a NP-hard problem. EEHRP seeks to obtain a Pareto optimal solution for the section of best MOO-based route under sensor node. The simulation results demonstrate that, relative to state-of-the-art solutions, EEHRP is efficient in terms of energy, throughput, delay, control- and routing-overheads. Furthermore, the paper investigates statistical significance of the findings obtained across confidence intervals. To prove EEHRP’s competence, a confidential interval of 95% is inserted into the simulation results obtained to represent margin of error around the estimated points. The on-hand state-of-art solutions and the propensity of the research fraternity in relation to MOO are also analyzed in this paper.

Campion: debugging router configuration differences

Abstract: We present a new approach for debugging two router configurations that are intended to be behaviorally equivalent. Existing router verification techniques cannot identify all differences or localize those differences to relevant configuration lines. Our approach addresses these limitations through a _modular_ analysis, which separately analyzes pairs of corresponding configuration components. It handles all router components that affect routing and forwarding, including configuration for BGP, OSPF, static routes, route maps and ACLs. Further, for many configuration components our modular approach enables simple _structural equivalence_ checks to be used without additional loss of precision versus modular semantic checks, aiding both efficiency and error localization. We implemented this approach in the tool Campion and applied it to debugging pairs of backup routers from different manufacturers and validating replacement of critical routers. Campion analyzed 30 proposed router replacements in a production cloud network and proactively detected four configuration bugs, including a route reflector bug that could have caused a severe outage. Campion also found multiple differences between backup routers from different vendors in a university network. These were undetected for three years, and depended on subtle semantic differences that the operators said they were "highly unlikely" to detect by "just eyeballing the configs."

FTC-OF: Forwarding Traffic Consciousness Objective Function for RPL Routing Protocol

Abstract: The rise of the Internet of Things (IoT) and the diversity of its applications make the need for a flexible routing protocol able to face several constraints very essential. In this context, the RPL protocol was designed to meet the need for IoT classified as low power and lossy networks (LLN's). RPL relies on an objective function that takes into account a metric to implement its routing strategy in the network. On the other hand, the problem consists of a single routing metric that sometimes leads to the selection of non-optimized or static routes in the network. As a consequence, two main problems emerge, the first is the congestion created in the nodes due to the high number of packets to be relayed which leads to their loss, the second is the greedy energy consumption by these nodes which can conduct to quickly degrade their batteries, thus losing and causing loss the connectivity of several nodes in the network. To remedy this problem, a novel objective function for RPL FTC-OF has been implemented in the core of the embedded operating system CONTIKI, which combines three different routing metrics, aiming to create a balanced network while considering the quality of link on a short path, namely hop count, RSSI and a newly designed metric called Forwarded Traffic Metric (FTM). The proposed method, considered as a new balancing strategy, evaluated under the COOJA emulator, outperforms ETX and Energy based RPL protocols. It shows that it increases the rate of packet delivery, considerably reduces the power consumption of the network as well as an almost perfect balance of traffic managed by the relay nodes.

Intent-based Networking Approach for Service Route and QoS control on KOREN SDI

Abstract: Intent-Based Networking (IBN) is a model that enables proactive network control and automation to satisfy high-level demands. It follows a closed-loop mechanism that abstracts the network complexity and dynamically allows updates to the network monitoring and intelligence. Hence, it eliminates the traditionally practiced error-prone manual network control. In contrast with the traditional reactive approach, IBN-based approach promotes the proactive and dynamic solution. To this end, IBN uses machine learning (ML) to predict the future and keeps a balance between the intended and actual state. Hence, this work considers an IBN-driven routing mechanism to ensure service provisioning with the desired quality of service (QoS). In contrast to the traditional static routing scheme, this work considers AI-driven dynamic and proactively updatable routing schemes to ensure QoS. This work demonstrates AI-driven service route control mechanism for ensuring quality of service (QoS) on top of Korea Advanced Research Network-Software Defined Infrastructure (KOREN-SDI). More precisely, an ML-based approach is used to find the best path between source and destination nodes. In addition, it incorporates IBN closed-loop process to monitor and update service routes proactively based on predicted future link utilization. This novel approach introduces proactive updates on runtime to avoid future failures and ensures seamless service provisioning with the fulfillment of QoS demands by changing traffic routes dynamically.

A Robust Method for Estimating the Channel Data Rate in Seamless IEEE 802.11ax Standard Networks

Abstract: In paper the robust method for estimating the channel data rate was developed for the collective dynamic routing method implementation in seamless IEEE 802.11ax standard networks. Collective dynamic routing method was analyzed with and without the use of a robust method in comparison with static routing by a seamless IEEE 802.11ax standard network segment example. The developed method makes it possible to significantly reduce the dimension of the valid routes set and, consequently, the computational complexity of the collective dynamic routing method implementation with a slight deterioration in its efficiency.

Improving the Performance of SDM-EON Through Demand Prioritization: A Comprehensive Analysis

Abstract: This paper studies the impact of demand-prioritization on Space-Division Multiplexing Elastic Optical Networks (SDM-EON). For this purpose, we solve the static Routing, Modulation Level, Spatial Mode, and Spectrum Assignment (RMLSSA) problem using 34 different explainable demand-prioritization strategies. Although previous works have applied heuristics or meta-heuristics to perform demand-prioritization, they have not focused on identifying the best prioritization strategies, their inner operation, and the implications behind their good performance by thorough profiling and impact analysis. We focus on a comprehensive analysis identifying the best explainable strategies to sort network demands in SDM-EON, considering the physical-layer impairments found in optical communications. Also, we show that simply using the common shortest path routing might lead to higher resource requirements. Extensive simulation results show that up to 8.33% capacity savings can be achieved on average by balanced routing, up to a 16.69% capacity savings can be achieved using the best performing demand-prioritization strategy compared to the worst-performing ones, the most used demand-prioritization strategy in the literature (serving demands with higher bandwidth requirements first) is not the best-performing one but the one sorting based on the path lengths, and using double-criteria strategies to break ties is key for a good performance. These results are relevant showing that a good combination of routing and demand-prioritization heuristics impact significantly on network performance. Additionally, they increase the understanding about the inner workings of good heuristics, a valuable knowledge when network settings forbid using more computationally complex approaches.

Network Automation using Ansible for EIGRP Network

Abstract: Network automation has evolved into a solution that emphasizes efficiency in all areas. Furthermore, communication and computer networks rely on a platform that provides the necessary technological infrastructure for packet transfer through the Internet using routing protocols. The Enhanced Interior Gateway Routing Protocol (EIGRP) is a hybrid routing protocol that combines the properties of both distance-vector and link-state routing methods. The traditional technique to configure EIGRP is inefficient and requires repeated processes compared to the network automation concept. Network automation helps to assist network administrators in automating and verifying the EIGRP configuration using scripting. This paper implemented network automation using Ansible to configure EIGRP routing and advanced configuration in the GNS3 environment. This study is focused on automated scripting to configure IP Addresses to the interfaces, EIGRP routing protocol, a default static route and advanced EIGRP configurations. Ansible ran the scripting on Network Automation Docker and pushed the configurations to the routers. The network automation docker communicated with other routers via SSH. In the testing phase, the running configuration between the traditional approach and automation scripting in the Ansible playbook was compared to verify EIGRP configurations' accuracy. The findings show that Ansible has successfully deployed the configuration to the routers with no errors. Ansible can help network administrators minimized human mistakes, reduce time-consuming and enable device visibility across the network environment. Implementing EIGRP authentication and hardening process can enhance the network security level for future study.

YANG Data Model for Segment Routing

Abstract: This document defines a YANG data model ([RFC6020], [RFC7950]) for segment routing ([RFC8402]) configuration and operation. This YANG model is intended to be used on network elements to configure or operate segment routing. This document defines also generic containers that SHOULD be reused by IGP protocol modules to support segment routing.

Scalable Node-Disjoint and Edge-Disjoint Multi-wavelength Routing.

Abstract: Probabilistic message-passing algorithms are developed for routing transmissions in multi-wavelength optical communication networks, under node and edge-disjoint routing constraints and for various objective functions. Global routing optimization is a hard computational task on its own but is made much more difficult under the node/edge-disjoint constraints and in the presence of multiple wavelengths, a problem which dominates routing efficiency in real optical communication networks that carry most of the world's Internet traffic. The scalable principled method we have developed is exact on trees but provides good approximate solutions on locally tree-like graphs. It accommodates a variety of objective functions that correspond to low latency, load balancing and consolidation of routes, and can be easily extended to include heterogeneous signal-to-noise values on edges and a restriction on the available wavelengths per edge. It can be used for routing and managing transmissions on existing topologies as well as for designing and modifying optical communication networks. Additionally, it provides the tool for settling an open and much debated question on the merit of wavelength-switching nodes and the added capabilities they provide. The methods have been tested on generated networks such as random-regular, Erdős Renyi and power-law graphs, as well as on the UK and US optical communication networks. They show excellent performance with respect to existing methodology on small networks and have been scaled up to network sizes that are beyond the reach of most existing algorithms.

Kombinasi Protokol Routing OSPF dan BGP dengan VRRP, HSRP, dan GLBP

Abstract: Vocational High Schools as educational institution that adopt vocation based curriculum get the advantages and benefits of the development of the teaching factory. Teaching factory is a product and business oriented concept of learning in response to the challenges and development of the industry. However, during the pandemic period, teaching factory management faces many obstacles, one of which is in the performance of the network. The current network uses static routing network protocol which has no backup line or track. It is, therefore, suggested to apply dynamic routing OSPF and BGP with the VRRP, HSRP, and the GLBP workload method as the backup line which is measured through the throughput, delay, and packet loss parameter, for its Quality of Service (QoS). The research scenario stage applies each routing protocol to each performance method, so that it can be measured to obtain the expected QoS results at end users. The best result that will be recommended is routing OSPF by VRRP method because it has less than 1 second time comparison when there is a network failure. It is shown in the QoS result of 3.96, which shows that it is very satistactory compared to others.

Social contact graph-based group communication schemes for delay tolerant networks

Abstract: Graphical AbstractMulticast routing employs a dynamic tree branching technique that allows routing paths to be efficiently shared among multicast destinations. Anycast routing balances the trade-off between a short path to the closest, single group member and a longer path over which many other group members reside.

Twitter Rumor Detection Technology Based on Hierarchical Capsule Network

Abstract: The widespread use of social media enables people to quickly and conveniently obtain and share information, and it also brings about the rapid spread of false information. A large number of online rumors flooded the social network media, which had a serious impact on people’s lives and social stability. The research on the detection technology of network rumors has become a hot research topic in recent years. The capsule network can clearly view the hierarchical structure of the data by viewing the activated path. This paper proposes a rumor detection model based on a hierarchical capsule network. The model can use static routing and dynamic routing to obtain clear input signals and accurately determine data information; the model fully takes into account the spatial structure characteristics of the text, effectively identify the content of the text. Therefore, this model can effectively improve the accuracy of rumor detection. This experiment uses twitter public datasets, under different conditions of dynamic routing and static routing, compared with the existing typical rumor detection models, the accuracy of the proposed model is improved by 6.1% and 5.6%.

Design and Implementation of LEO Micro-Satellite Network Routing Protocol based on Virtual Topology

Abstract: According to the typical constellation configuration, this paper analyzes the constellation network topology, and designs a routing protocol with convergence capabilities and a Media Access Control layer protocol which uses time division multiple access to allocate different time slots to control data flow. A routing mechanism with a virtual topology is established, and a static routing table is set according to the predictable characteristics of the orbit, which is suitable for the same orbit as well as for different orbits. This article uses OPNET simulation software to model the entire network system, simulate the multi-hop constellation network, and obtain and analyze the network's time delay, throughput and other indicators. The simulation results show that the routing protocol has a good performance in the constellation network.

Dynamic routing for accelerated deep learning

Abstract: Techniques in dynamic routing for advanced deep learning provide improvements in one or more of accuracy, performance, and energy efficiency. An array of processing elements comprising a portion of a neural network accelerator performs flow-based computations on wavelets of data. Each processing element comprises a compute element enabled to execute programmed instructions using the data and a router enabled to route the wavelets via static routing, dynamic routing, or both. The routing is in accordance with a respective virtual channel specifier of each of the wavelets and controlled by routing configuration information of the router. The static techniques enable statically specifiable neuron connections. The dynamic techniques enable information from the wavelets to alter the routing configuration information during neural network processing.

Network quality measurement method and device, server, and computer readable medium

Abstract: Embodiments of the present application provides a network quality measurement method, comprising: determining a suspected path of a service flow for measurement according to a preset static routing database; sending a subscription command to a network element device on the suspected path; receiving data sent from the network element device in response to the subscription command; determining a real path of the service flow according to the data, the static routing database, and the suspected path; and measuring the network quality on the real path according to the data and a preset index threshold. The embodiments of the present application also provide a network quality measurement device, a server, and a computer readable medium.

Rapid and verifiable network configuration repair

Abstract: Discussed herein is technology for verifiable network configuration repair. A method can include adding a routing adjacency or route redistribution edge to a router of an aETG to generate an enhanced aETG (eaETG), adding, for each dETG of dETGs, static route edges to a destination of the dETG to generate an enhanced dETG (edETG), determining, for each of the edETGs, all simple paths from all sources to the destination of the edETG, determining a set of paths (pathtset) over the determined simple paths that satisfies the policies, and translating the edge additions and/or removals in the eaETG and in the edETGs to an addition and/or removal of one or more of a routing adjacency, routing filter, or static route based on the determined pathset.

Advantages of Method of Collective Dynamic Routing in IP Networks

Abstract: This article discusses the main features of the collective dynamic routing method. Expressions are given for the implementation of the main stages of the collective dynamic routing method. Examples of constructing valid one-dimensional and multidimensional routes for an arbitrary IP network, as well as the features of the collective dynamic routing implementation in classical and software-defined networking are considered. The analysis was provided, showing the decreasing mean delivery time for the collective dynamic routing method compared with static routing for various traffic types. It is also shown that using collective dynamic routing method reduces the mean delivery time and increases the network throughput as a whole for the broadband radio access network fragment when transmitting real traffic.

A method and an apparatus for routing data packets in a network

Abstract: The embodiments herein relate to a method and a router device (700, 101) for routing data packets using virtual routing and forwarding (VRF). The method includes; configuring (601) a first loopback interface and assigning a first VRF (VRF1); configuring (602) a second loopback interface and assigning a second VRF (VRF2); configuring (603, 604) first and second GRE tunnels and assigning the tunnels to respective VRF; assigning (605, 605) for each GRE tunnel a source and a destination point, configuring (607) source and destination IP addresses of both GRE tunnels to use the same routing table from a routing table of VRF1 or from a routing table of VRF2; configuring (608) a first static to route data packets destined to a network behind VRF2; and configuring (609) a second static route to route data packets destined to a network behind VRF1.