Link Failure Recovery in SDN: High Efficiency, Strong Scalability and Wide Applicability

Abstract

Link failures are commonly observed in computer networks, including the newly emerging Software Defined Network (SDN). Considering that failure recovery methods used in traditional networks cannot be applied to SDN networks directly, we propose a method named pro-VLAN in this paper, which calculates a backup path and assigns a unique VLAN id for each link of the network based on the protection mechanism. It makes the most of SDN’s features and can recover a single link failure in SDN with the advantages of high efficiency, strong scalability and wide applicability. More specifically, high efficiency (i.e., a fast failure recovery with a low memory consumption) is achieved by calculating backup paths for each link instead of each flow and using group tables to switch backup paths automatically and locally when failures occur. Strong scalability (i.e., the amount of backup flow entries per switch is stable) is achieved by keeping the amount of links per switch no matter how the network scale extends or how the amount of flows increases. Wide applicability is achieved by always finding a path available without modifying any hardware or protocol as long as the network is still reachable after a link failure. Simulation results and mathematical analysis demonstrate that both pro-VLAN and a flow-based protection method achieve a fast failure recovery, while pro-VLAN consumes less than 1% of the forwarding entries to store backup paths as compared to the flow-based method. Moreover, when the network scale increases from 10 to 60 switches by 500%, the increase of the number of backup flow entries per switch built by pro-VLAN is only less than 50%.

Survey of optimizing dynamic virtual local area network algorithm for software-defined wide area network

“…Chen et al [34] propose a protection VLAN (pro-VLAN) solution that determines an exact backup path and assigns a single VLAN ID to each network connection that the security system supports. It takes advantage of the most critical features of SDN and can recover one connection loss in SDN, all while offering high performance, scalability, and applicability.…”

Data plane failure and its recovery techniques in SDN: A systematic literature review

“…Although it performs on a small-scale network, It has scalability issues. The researcher [72] proposed the pro-Vlan methods for single link failure by using group tables to calculate the backup path for each link only by assigning a vlan id. Reduce memory consumption, improve scalability, and be free of flows-based protection.…”

Recovery and Reconstruction of Multicast Tree in Software-Defined Network: High Speed and Low Cost

“…Capone et al [48] and Cascone et al [49] import the concept of a stateful switch (named ''OpenState'') to execute the programmed recovery behaviors directly which can promise packets are forwarded along shortest backup paths after failures. Our previous work proposes a method named ''Pro-VLAN'' [42], [50] which is suitable for the unicast scenario, based on the protection mechanism and calculates a backup path for each link, resulting in a fast failure recovery and less consumption of TCAMs when compared with other protection-based methods.…”

“…This paper adopts the method which has been introduced in our previous paper [42] in detail. We call the proposed method by ''Pro-VLAN'' as it is based on the protection mechanism and each network component is assigned a unique VLAN ID for distinguishing from each other.…”

“…• In a grid network [42], [50], there is more than one path between any two nodes. A grid network can be seen as a special case of a mesh network: a mesh network without end point nodes.…”