Rerouting Mechanism Research Articles

Demand rerouting mechanisms with revenue management for intermodal barge transportation networks

Inland waterway transportation plays a crucial role in Europe's transportation network and economy. It is an efficient and sustainable mode of transportation, with lower emissions and energy consumption than other modes of transportation, such as road and air. However, the services provided by inland waterway transport can be significantly impacted by adverse weather conditions such as heavy rain, strong winds, and flooding. These disruptions can cause delays, cancellations, or even damage to vessels or infrastructure. To improve the system reliability, we propose a set of revenue management based (demand itinerary) rerouting mechanisms for intermodal barge transportation optimisation. Revenue Management policies including several customer categories and fare differentiation are applied. Sequential accept/reject decisions are made based on a probabilistic mixed integer programming model maximising the expected revenue of a carrier. A booking framework is defined over a rolling horizon and capacity allocation/reallocation decisions are made for a set of demands including the current and relevant past and potential future transportation requests. Several (demand) rerouting mechanisms are defined and implemented on different service network configurations. The service network status is regularly updated, in particular with respect to barge capacity variations due to changing water levels. An extensive set of experiments is performed and numerical results are analysed. The study results emphasise the added value but also the need for data availability and information sharing between the different stakeholders of Inland Waterway Transportation systems.

MOLM: Alleviating Congestion through Multi-Objective Simulated Annealing-Based Load Balancing Routing in LEO Satellite Networks

In satellite networks, existing congestion resolution methods do not consider the predictability and stability of paths, leading to frequent path switches and high maintenance costs. In this regard, we propose a novel congestion resolution approach, named MOLM, which introduces a continuous neighbor set during path updates. This set includes nodes capable of establishing sustainable connections with the predecessors and successors of congested nodes. Combined with a multi-objective simulated annealing framework, MOLM iteratively derives an optimal selection from this set to replace congested nodes. Additionally, we employ a Fast Reroute mechanism based on backup paths (FRR-BP) to address node failures. The simulation results indicate that the optimal node endows the new path with optimal path stability and path latency.

Software Defined Multicast Using Segment Routing in LEO Satellite Networks

The emerging low earth orbit (LEO) broadband satellite networks are creating new opportunities to enable superior video distribution. With numerous satellites deployed, broadband constellations are capable of distributing videos across the globe by efficient multicasting techniques. However, existing work only studied IP multicast for broadband constellations, which suffer from limited scalability and tree performance. With recent breakthroughs in software defined networking, novel software defined multicasting (SDM) techniques manage to achieve efficient data transfer through intelligent and granular management, outperforming traditional IP Multicast. This paper leverages software defined multicasting in the promising broadband constellations to empower satellite-based Internet video distribution. Based on rectilinear Steiner trees, this paper proposes a novel software defined multicasting framework for broadband satellite networks. In addition, this paper designs simple, agile, and scalable multicast segment routing protocols implementing source routing and equal cost multipath routing. The proposed protocols also adapt to frequent member updates and network failures with efficient tree recovery and local rerouting mechanisms. Comprehensive experiments demonstrate the effectiveness and efficiency of our approach when compared with traditional algorithms.

Proposed enhanced link failure rerouting mechanism for software-defined exchange point

Internet eXchange point (IXP) is a way to optimize network bandwidth. It enables a platform in the different providers like internet service providers (ISPs) and content delivery providers (CDNs) to share their traffic through a common point. A software defined exchange point (SDX) is an IXP comprising of a programmable deployed software defined network (SDN) switching fabric to enhance the management of their services, but they met the performance issues. The previous studies proposed various mechanisms and frameworks that tackled with these issues, but they don’t overcome overall challenges like link failure recovery for multi-hop-based SDX particularly packet processing delay and switch memory overhead. To cope with these issues, this paper proposed an enhanced link failure rerouting (ELFR) mechanism for multi-hop-based SDX. The objective of the proposed ELFR mechanism is to reduce the delay of packet processing to recover the link failure quickly and improve the path computation while ensuring the switch storage overhead. The present paper is an effort to retrospect and analyze the critical review of existing work for SDX. Furthermore, this paper provides a background of SDX, its components and its applications. Finally, this paper presents and compares the expected results of ELFR mechanism and related work.

Comparison of New Solutions in IP Fast Reroute

Currently, network requirements are placed on the efficiency and size of the networks. These conditions can be ensured by modern converged networks that integrate the functions of both data and telecommunication networks. Line or router failures have always been a part of transmission networks, which is no different from converged networks. As a result of outages, which can take from ms to tens of seconds, packets are lost. These outages cause degraded transmission quality, which is undesirable when transmitting real-time multimedia services (Voice over IP, video). To solve the mentioned problems, the IETF organization has developed IP Fast Reroute mechanisms to minimise the time to restore the connection after a line or node failure and, consequently, less packet loss. The article reviews and compares the latest IP Fast Reroute mechanisms deployed in the last three years. First, we have Optimistic Fast Rerouting, which calculates optimistic and fallback scenarios. The second is Post-processing Fast Reroute, which decomposes the network according to metrics such as load and route length. Third, Local Fast Reroute focused on low congestion and random access.

Existing Fast Reroute Mechanisms in SDN

Nowadays, the implementation of networks using software-defined resource environments is becoming more and more widespread. As with classic IP networks, it is necessary to consider possible complications that occur during connectivity failures (packet loss, unavailable services, congestion). A critical aspect when a connection fails is the time required to restore it. In Software-Defined Networks (SDN), where topologies are large, there are several ways to look for ways to improve network recovery speed. Fast Reroute solutions have been developed to solve negative impacts after link or node failure in SDN.This paper introduces current Fast Reroute mechanisms in Software-defined networking (SDN). The most used mechanisms include Openflow Fast Failover groups, OpenState failover technique, Loop-free Alternate (LFA) and Remote LFA (RLFA).

Segment routing for traffic engineering and effective recovery in low-earth orbit satellite constellations

Low-Earth Orbit Satellite Constellations (LEO-SCs) provide global, high-speed, and low latency Internet access services, which bridges the digital divide in the remote areas. As inter-satellite links are not supported in initial deployment (i.e. the Starlink), the communication between satellites is based on ground stations with radio frequency signals. Due to the rapid movement of satellites, this hybrid topology of LEO-SCs and ground stations is time-varying, which imposes a major challenge to uninterrupted service provisioning and network management. In this paper, we focus on solving two notable problems in such a ground station-assisted LEO-SC topology, i.e., traffic engineering and fast reroute, to guarantee that the packets are forwarded in a balanced and uninterrupted manner. Specifically, we employ segment routing to support the arbitrary path routing in LEO-SCs. To solve the traffic engineering problem, we proposed two source routings with traffic splitting algorithms, Delay-Bounded Traffic Splitting (DBTS) and DBTS+, where DBTS equally splits a flow and DBTS ​+ ​favors shorter paths. Simulation results show that DBTS ​+ ​can achieve about 30% lower maximum satellite load at the cost of about 10% more delay. To guarantee the fast recovery of failures, two fast reroute mechanisms, Loop-Free Alternate (LFA) and LFA+, are studied, where LFA pre-computes an alternate next-hop as a backup while LFA ​+ ​finds a 2-segment backup path. We show that LFA ​+ ​can increase the percentage of protection coverage by about 15%.

Cooperative Exchange-Based Platooning Using Predicted Fuel-Optimal Operation of Heavy-Duty Vehicles

Several driving situations exist where fuel-optimal driving in terms of aggregate performance can only be achieved when one or more vehicles incurs a sacrifice in its own fuel consumption. For these situations, an economic incentive is needed to entice that vehicle to participate in aggregate fuel-optimal driving. Focusing on platooning amongst automated heavy-duty vehicles and using real trucking routes, we examine the precise extent to which the benefits of platooning can be expanded through the incorporation of exchange-based incentives. We focus on two mechanisms for incentivized platooning: (i) incentivized “catch-up” along a prescribed highway route and (ii) incentivized re-routing to allow for platooning. For the incentivized “catch-up” mechanism, platoon capable vehicles begin at staggered positions, using a novel platoon catch-up algorithm capable of determining the fuel-optimal platoon engagement position and fuel-optimal velocity trajectories. Additionally, the incentivized re-routing mechanism determines the optimal route for a network of platoon-capable vehicles, allowing for a vehicle to reroute its trajectory to engage within the platoon. Because such scenarios will be shown to frequently lead to aggregate benefit, while actually hurting the fuel economy of one or more participants, we propose three methods for explicitly computing the monetary value of the exchange. Assuming a known trajectory and traffic pattern, the first uses the Shapley value to determine the exchange value. The second method adjusts the Shapley value, accounting for uncertainty associated with traffic modeling. The final method assumes a competitive market, requiring each individual operator to implement a bid.

Early detection of link failures through the modeling of the hardware deterioration process

Network failures can significantly degrade the network performance in several ways, ranging from experiencing unacceptable delays (e.g., in video conference applications) to leading to significant drops in sales for companies (e.g., airlines tickets purchases). In this paper, we focus on network failures caused by links that are prone to fail due to their advanced stage of lifetime. In particular, the formalization of the Hardware Deterioration Failure Mode (HDFM) for network line cards is provided to evaluate the penalty for network operators of handling HDFM failing links using classical methods based on Bidirectional Forwarding Detection and Fast Re-Route mechanisms. An algorithm, named Hardware Deterioration Detection (HDD), is proposed to detect if links are experiencing failures as well as to provide an estimation of their remaining lifetime. The performance evaluation over data generated by our provided network failure simulator shows that HDD is able to correctly classify links as failing or not failing, regardless of the type of failure considered. Moreover, overall descriptions for failure models in which HDD is able to produce high quality estimations of the remaining lifetime have been identified, with a trade-off between the hardware deterioration time dependence and the relationship between lifetime and packet loss probability.

Fast ReRoute on Programmable Switches

Highly dependable communication networks usually rely on some kind of Fast Re-Route (FRR) mechanism which allows to quickly re-route traffic upon failures, entirely in the data plane. This paper studies the design of FRR mechanisms for emerging reconfigurable switches. Our main contribution is an FRR primitive for programmable data planes, PURR, which provides low failover latency and high switch throughput, by avoiding packet recirculation. PURR tolerates multiple concurrent failures and comes with minimal memory requirements, ensuring compact forwarding tables, by unveiling an intriguing connection to classic “string theory” (i.e., stringology), and in particular, the shortest common supersequence problem. PURR is well-suited for high-speed match-action forwarding architectures (e.g., PISA) and supports the implementation of a broad variety of FRR mechanisms. Our simulations and prototype implementation (on an FPGA and a Tofino switch) show that PURR improves TCAM memory occupancy by a factor of 1.5 ×- 10.8 × compared to a naïve encoding when implementing state-of-the-art FRR mechanisms. PURR also improves the latency and throughput of datacenter traffic up to a factor of 2.8 ×- 5.5 × and 1.2 ×- 2 ×, respectively, compared to approaches based on recirculating packets.

Enhanced Bit Repair IP Fast Reroute Mechanism for Rapid Network Recovery

The massive development of virtualized infrastructures, Internet of Things (IoT), and Wireless Sensor Network (WSN) in recent years has led to an increase in quality requirements for the management and reliability of underlay communication networks. Existing converged networks must therefore guarantee specific quantitative and qualitative parameters of different network communication services to meet customer requirements. However, the quality of the services operated is very negatively affected by an unpredictable failure of a communication link or a network node. In such situations, communication is typically interrupted for a period that is difficult to predict, and which can lead to significant financial losses and other negative effects. Internet Protocol Fast Reroute (IP FRR) technology was developed for these reasons. The paper presents the proposal of the new Enhanced Bit Repair (EB-REP) IP FRR mechanism, which offers significant improvements over its predecessor, the B-REP mechanism. The B-REP offers protection against a single failure and only for selected critical IP flows. The EB-REP provides advanced protection against multiple failures in a protected network domain and the protection can be provided for all network flows. The EB-REP calculates alternative paths in advance based on link metrics, but also allows the construction of alternative paths independently of them. The construction of alternative FRR paths uses a standardized tunneling approach via a unique field Bit-String. Thanks to these features, EB-REP is an advanced contribution to solving IP FRR-related problems, which enables the use of EB-REP in many network deployments, but especially in network solutions that require reliable data transmission.

A New Bit Repair Fast Reroute Mechanism for Smart Sensors IoT Network Infrastructure.

Today’s IP networks are experiencing a high increase in used and connected Internet of Things (IoT) devices and related deployed critical services. This puts increased demands on the reliability of underlayer transport networks. Therefore, modern networks must meet specific qualitative and quantitative parameters to satisfy customer service demands in line with the most common requirements of network fault tolerance and minimal packet loss. After a router or link failure within the transport network, the network convergence process begins. This process can take an unpredictable amount of time, usually depending on the size, the design of the network and the routing protocol used. Several solutions have been developed to address these issues, where one of which is the group of so-called Fast ReRoute (FRR) mechanisms. A general feature of these mechanisms is the fact that the resilience to network connectivity failures is addressed by calculating a pre-prepared alternative path. The path serves as a backup in the event of a network failure. This paper presents a new Bit Repair (B-REP) FRR mechanism that uses a special BIER header field (Bit-String) to explicitly indicate an alternative path used to route the packet. B-REP calculates an alternative path in advance as a majority of existing FRR solutions. The advantage of B-REP is the ability to define an alternative hop-by-hop path with full repair coverage throughout the network, where, unlike other solutions, we propose the use of a standardized solution for this purpose. The area of the B-REP application is communication networks working on the principle of packet switching, which use some link-state routing protocol. Therefore, B-REP can be successfully used in the IoT solutions especially in the field of ensuring communication from sensors in order to guarantee a minimum packet loss during data transmission.

P4-based implementation of BIER and BIER-FRR for scalable and resilient multicast

Bit Indexed Explicit Replication (BIER) is a novel IP multicast (IPMC) forwarding paradigm proposed by the IETF. It offers a transport layer for other IPMC traffic, keeps core routers unaware of IPMC groups, and utilizes a routing underlay, e.g., an IP network, for its forwarding decisions. With BIER, core networks do not require dynamic signaling and support a large number of IPMC groups with large churn rates. The contribution of this work is threefold. First, we propose a novel fast reroute (FRR) mechanism for BIER (BIER-FRR) so that IPMC traffic can be rerouted as soon as the routing underlay is able to carry traffic again after a failure. In particular, BIER-FRR enables BIER to profit from FRR mechanisms in the routing underlay. Second, we describe a prototype for BIER and BIER-FRR within an IP network with IP fast reroute (IP-FRR). It is based on the programmable data plane technology P4. Third, we propose a controller hierarchy with local controllers for local tasks, in particular to enable IP-FRR and BIER-FRR. The prototype demonstrates that BIER-FRR reduces the protection time for BIER traffic to the protection time for unicast traffic in the routing underlay.

Enhanced Multicast Repair Fast Reroute Mechanism for Smart Sensors IoT and Network Infrastructure.

The sprawling nature of Internet of Things (IoT) sensors require the comprehensive management and reliability of the entire network. Modern Internet Protocol (IP) networks demand specific qualitative and quantitative parameters that need to be met. One of these requirements is the minimal packet loss in the network. After a node or link failure within the network, the process of network convergence will begin. This process may take an unpredictable time, mostly depending on the size and the structure of the affected network segment and the routing protocol used within the network. The categories of proposed solutions for these problems are known as Fast ReRoute (FRR) mechanisms. The majority of current Fast ReRoute mechanisms use precomputation of alternative backup paths in advance. This paper presents an Enhanced Multicast Repair (EM-REP) FRR mechanism that uses multicast technology to create an alternate backup path and does not require pre-calculation. This principle creates a unique reactive behavior in the Fast ReRoute area. The enhanced M-REP FRR mechanism can find an alternative path in the event of multiple links or nodes failing at different times and places in the network. This unique behavior can be applied in the IoT sensors area, especially in network architecture that guarantees reliability of data transfer.

Improved Fast Rerouting Using Postprocessing

To provide fast traffic recovery upon failures, most modern networks support static Fast Rerouting (FRR) mechanisms for mission critical services. However, configuring FRR mechanisms to tolerate <i>multiple</i>failures poses challenging algorithmic problems. While state-of-the-art solutions leveraging arc-disjoint arborescence-based network decompositions ensure that failover routes always reach their destinations eventually, even under multiple concurrent failures, these routes may be long and introduce unnecessary loads; moreover, they are tailored to worst-case failure scenarios. This article presents an algorithmic framework for improving a given FRR network decomposition, <i>using postprocessing</i>. In particular, our framework is based on iterative arc swapping strategies and supports a number of use cases, from strengthening the resilience (e.g., in the presence of shared risk link groups) to improving the quality of the resulting routes (e.g., reducing route lengths and induced loads). Our simulations show that postprocessing is indeed beneficial in various scenarios, and can therefore enhance today&#x2019;s approaches.

Survivability-aware routing restoration mechanism for smart grid communication network in large-scale failures

Natural disasters such as earthquakes have consecutive impacts on the smart grid because of aftershock activities. To guarantee service requirements and smart grid stable operations, it is a challenge to design a fast and survivable rerouting mechanism. There are few studies that consider concurrent rerouting aiming at multiple services in smart grid communication network, however. Firstly, we formulate the node survivability, link survivability, and path survivability model in terms of the distance from the epicenter to the node and the link of the network. Meanwhile, we introduce the indicator of site difference level which is unique in the smart grid to further restrict the service path. Secondly, to improve the algorithm efficiency and reduce rerouting time, the deep first search algorithm is utilized to obtain the available rerouting set, and then the I-DQN based on the framework of reinforcement learning is proposed to achieve concurrent rerouting for multiple services. The experimental results show that our approach has a better convergence performance and higher survivability as well as the approximate latency in comparison with other approaches.

Efficient Recovery Path Computation for Fast Reroute in Large-Scale Software-Defined Networks

With an increasing demand for resilience in software-defined networks (SDN), it becomes critical to minimize service recovery delay upon route failures. Fast reroute (FRR) mechanisms are widely used in IP and MPLS networks by computing the recovery path before a failure occurs. The centralized control plane in SDN can potentially enhance path computation, so that FRR path computation can better scale in SDN than in traditional networks. However, the traditional FRR path computation algorithms could lead to a poor performance in large-scale SDN. The problem can become more severe for a highly dynamic network, which often sees dozens of failures or configuration changes in any single day. We propose a new algorithm that exploits pruned searching to quickly compute recovery paths for all-pair switches/hosts upon a link failure. For applications requiring stringent path robustness levels, we also extend this algorithm to quickly find the shortest guaranteed-cost path, which ensures that the recovery path used upon on-path link failures has the minimum cost. Compared with traditional solutions, our evaluations show that our algorithm is about 8 ~ 81 times faster than the practical implementation, 1.93 ~ 3.11 times faster than the state-of-the-art solution. Our results also show that the shortest guaranteed-cost path can reduce the cost of the recovery path significantly. Moreover, we design a prototype to show how to deploy our algorithm in an OpenFlow network.

Load-Optimal Local Fast Rerouting for Dense Networks

Reliable and highly available computer networks must implement resilient fast rerouting mechanisms: upon a link or node failure, an alternative route is determined quickly, without involving the network control plane. Designing such fast failover mechanisms capable of dealing with multiple concurrent failures, however, is challenging, as failover rules need to be installed proactively , i.e., ahead of time, without knowledge of the actual failures happening at runtime. Indeed, only little is known today about the design of resilient routing algorithms. This paper introduces a general framework to reason about and design local failover algorithms that minimize the resulting load after failover on dense networks, beyond destination-based routing. We show that due to the inherent locality of the failover decisions at runtime, the problem is fundamentally related to the field of distributed algorithms without coordination . We derive an intriguing lower bound on the inherent network load overhead any local fast failover scheme that will introduce in the worst case, even though globally seen, much more balanced traffic allocations exist. We then present different randomized and deterministic failover algorithms and analyze their overhead load. In particular, we build upon the theory of combinatorial designs and develop a novel deterministic failover mechanism based on symmetric block design theory , which tolerates a maximal number of link failures while ensuring low loads.

Packet Loss and Packet Delivery Evaluation Using Network Simulator for Multicast Enabled Network Mobility Management

This paper investigates packet loss issue in multicast enabled network mobility management using network simulator. Network mobility management namely PMIPv6 has the capacity to reduce mobile IPv6 performance problems. But PMIPv6 basic architecture is limited to unicast communication. Therefore, this paper proposes PMIPv6 with context delivery and multicast fast reroute mechanisms to enable multicast services. In this paper, the configuration of multicast enabled PMIPv6 is done in network simulator called NS3. The aimed is to solve packet loss problem. This paper assumes that packet loss as the number of packets that are lost in a multicast communication. Packet loss is unescapable particularly in mobile multicast communication. It is a network system requirement to meet the threshold value of acceptable packet loss rate below than 5%. The packet loss ratio and the packet delivery ratio are extracted from the trace-file produced by the simulation process in NS3 simulator. The analyses of the packet loss ratio and packet delivery ratio are hereby presented. Keywords: NS3, Packet Loss, Packet Delivery, Mobile Multicast

Secure Buffer-Based Routing Protocol for WMN

Secure routing is considered as one of a key challenge in mesh networks because of its dynamic and broadcasting nature. The broadcasting nature of mesh environment invites number of security vulnerabilities to come and affect the network metrics drastically. Further, any node/link failure of a routed path may reduce the performance of the entire network. A number of secure routing protocols have been proposed by different researchers but enhancement of a single network parameter (i.e. security) may affect another performance metrics significantly i.e. throughput, end to end delay, packet delivery ratio etc. In order to ensure secure routing with improved network metrics, a Secure Buffer based Routing Protocol i.e. SBRP is proposed which ensures better network performance with increased level of security. SBRP protocol uses buffers at alternate positions to fasten re-routing mechanism during node/link failure and ensures the security using AES encryption. Further the protocol is analyzed against mAODV protocol in both static and dynamic environment in terms of security, packet delivery ratio, end to end delay and network throughput.