An enhanced dynamic multilayer routing for networks with protection requirements (original) (raw)
Related papers
Incorporating Protection Mechanisms in the Dynamic Multi-layer Routing Schemes
Lecture Notes in Computer Science, 2007
In the next generation backbone networks, IP/MPLS over optical networks, the ability to maintain an acceptable level of reliability has become crucial since a failure can result in a loss of several terabits of data per second. Although routing schemes with protection exist, they generally relate to a single switching layer: either wavelength or packet switching oriented. This paper presents a new dynamic and multi-layer routing scheme with protection that considers cooperation between IP/MPLS and optical switching domains. A complete set of experiments proves that the proposed scheme is more efficient when compared to routing algorithms with full optical protection or full IP/MPLS protection.
Dynamic protection using integrated-routing approach in IP-over-WDM networks
Computer Networks, 2003
This paper presents an efficient protection scheme to dynamically allocate restorable bandwidth-guaranteed paths in integrated IP-over-wavelength division multiplexing (WDM) networks. A restorable bandwidth-guaranteed path implies an active path and another link-disjoint backup path both with the required bandwidth. In this paper, we propose two integrated-routing algorithms: hop-based integrated-routing algorithm (HIRA) and bandwidth-based integrated-routing algorithm (BIRA) to allocate the paths. We use connection blocking probability and number of optical-electrical-optical (o-e-o) conversions as performance metrics. Through extensive simulation experiments, we demonstrate that our algorithms perform better than other existing approaches.
An Efficient Routing Method for Protection Data Flow in the MPLS Network
Journal of Science and Technology, 2017
This paper presents an efficient method for rerouting traffic in the Multiprotocol Label Switching (MPLS) network, when a fault occurs in the working link. The method has been designed to handle both single and multiple faults based on the protection switching and rerouting techniques. The proposed method leads to less packets loss, has better Packet Delivery Ratio (PDR), good throughput and eliminates packet disorder. The proposed method has been simulated using the Network Simulator (NS2) version 2.34 and the simulation results have shown that the proposed method significantly improves the network performance in comparison to similar existing methods.
Lecture Notes in Computer Science, 2004
We investigate the problern of Label Switched Path (LSP) protection using online integrated routing in IP over WDM networks. While certain mission-and time-critical applications require guaranteed 100% protection, other applications may have less stringent protection requirements. We consider these two kinds of protection seenarios and refer them as full protection (FP) and partial protection (PP), respectively. We first consider the full protection scenario and develop two integrated routing algorithms to select primary LSPs and backup LSPs, respectively. Next we consider the partial protection scenario, particularly, the partial spatial-protection (PSP) wherein the working traffic is unprotected against the failure of certain links along the primary LSPs according to the specified connection protection requirements. We develop an algorithm to determine the set of unprotected links with the objective of improving the backup resource sharing efficiency. We evaluate the performance of the proposed algorithms on the NSFNET and Pan-European optical networks.
A novel path protection scheme for MPLS networks using multi-path routing
Computer Networks, 2009
Multi-protocol label switching (MPLS) is an evolving network technology that is used to provide traffic engineering (TE) and high speed networking. Internet service providers, which support MPLS technology, are increasingly demanded to provide high quality of service (QoS) guarantees. One of the aspects of QoS is fault tolerance. It is defined as the property of a system to continue operating in the event of failure of some of its parts. Fault tolerance techniques are very useful to maintain the survivability of the network by recovering from failure within acceptable delay and minimum packet loss while efficiently utilizing network resources. In this paper, we propose a novel approach for fault tolerance in MPLS networks. Our approach uses a modified (k, n) threshold sharing scheme with multi-path routing. An IP packet entering MPLS network is partitioned into n MPLS packets, which are assigned to node/link disjoint LSPs across the MPLS network. Receiving MPLS packets from k out of n LSPs are sufficient to reconstruct the original IP packet. The approach introduces no packet loss and no recovery delay while requiring reasonable redundant bandwidth. In addition, it can easily handle single and multiple path failures.
Lecture Notes in Computer Science, 2004
In this paper we propose the concept of an end-to-end (e2e) Self-Protecting Multi-Path (SPM) as a protection switching mechanism that may be implemented, e.g., in Multiprotocol Label Switching (MPLS) networks. In case of local outages, resilient networks redirect the traffic from a failed link over an e2e backup path to its destination. In this case, Quality of Service (QoS) can only be provided if sufficient extra capacity is available. If backup capacity can be shared among different backup paths, multi-path routing allows for considerable savings regarding this extra capacity. The SPM consists of disjoint paths that carry the traffic bothin normal operation mode and during local outages. If a partial path is affected by a network failure, the traffic is just distributed to the remaining working paths. This structure is easy to configure and the switching to failure mode operation is simple since no signalling is required. Based on analytical results, we show that Ioad balancing of the traffic across the disjoint paths can reduce the required backup capacity significantly. The backup performance depends strongly on the network topology, and the SPM outperforms simple Open Shortest Path First (OSPF) rerouting by far.
Optical Switching and Networking, 2005
This paper investigates the problem of dynamic survivable lightpath provisioning against single node/link failures in optical mesh networks employing wavelength-division multiplexing (WDM). We unify various forms of segment protection into generalized segment protection (GSP). In GSP, the working path of a lightpath is divided into multiple overlapping working segments, each of which is protected by a node/link disjoint backup segment. We design an efficient heuristic which, upon the arrival of a lightpath request, dynamically divides a judiciously-selected working path into multiple overlapping working segments and computes a backup segment for each working segment while accommodating backup sharing. Compared to the widely-considered share-path protection scheme, GSP achieves much lower blocking probability and shorter protection-switching time for a small sacrifice in control and management overhead. Based on generalized segment protection, we present a new approach to provisioning lightpath requests according to their differentiated quality-of-protection (QoP) requirements. We focus on one of the most important QoP parameters-namely, protection-switching timesince lightpath requests may have differentiated protectionswitching-time requirements. For example, lightpaths carrying voice traffic may require 50-ms protection-switching time while lightpaths carrying data traffic may have a wide range of protection-switching-time requirements. Numerical results show that our approach achieves significant performance gain which leads to a remarkable reduction in blocking probability. While our focus is on optical WDM network, the basic ideas of our approaches can be applied to Multi-Protocol Label Switching (MPLS) networks with appropriate adjustments, e.g., differentiated bandwidth granularities.
Reliable services with fast protection in IP/MPLS over optical networks
Journal of Optical Networking, 2006
We define new quality-of-service (QoS) routing schemes with protection in Internet Protocol (IP)/Multiprotocol Label Switching (MPLS) over optical networks. The novelty of the proposed routing schemes is the use of the knowledge of the logical links already protected by the optical layer. The logical topology defined by the optical layer is given and fixed, and we assume that it is partially protected. Thereby, at the IP/MPLS layer, spare capacity is reserved to protect only those links that are unprotected. Moreover, we also characterize the traffic services based on their level of reliability and QoS requirements. In order to guarantee fast protection, segment protection and shared backups are combined, resulting in suitable fault recovery time and resource consumption. A complete set of experiments proves that the proposed schemes are more efficient than the previous ones in terms of resources used to protect the network, failure impact, and blocking probability.
Designing fast and bandwidth efficient protection scheme for WDM optical networks
2006
In this paper, we introduce the Pre-cross-connected Segment First-PXSFirst protection scheme; a new path-based protection schemes for WDM optical networks. The goal of the PXSFirst scheme is to achieve fast recovery, while maximizing bandwidth sharing to improve bandwidth utilization. Similar to pre-cross-connected trails (PXTs) protection scheme, PXSFirst ensures that all backup paths are pre-crossconnected, and hence eliminates the switching configuration delay along backup paths. However, unlike the PXT scheme, where backup paths can only share trails, PXSFirst breaks backup paths into smaller segments by existing end nodes, and hence, increases the possibility of bandwidth sharing. Extensive simulation results for different network topologies and under different traffic patterns show that the proposed scheme has better blocking performance and less bandwidth utilization (an average of 11.0% reduction) compared to existing PXT protection schemes.