Abstract. This paper proposes an integrated network management framework for interdomain outbound traffic engineering. The framework consists of three functional blocks (monitoring, optimization and implementation) to make the outbound traffic engineering adaptive to network condition changes such as inter-domain traffic demand variation, routing changes and link failure. The objective is to keep inter-domain link utilization load balanced under any of these changes while reducing service disruptions and reconfiguration overheads. Simulation results demonstrate that using the proposed framework can successfully achieve better load balancing with less service disruptions and re-configuration overheads compared to the alternative approaches.
IntroductionOutbound Traffic Engineering (TE) [1,2,3,4] has become increasingly important and been well studied, and is a set of techniques for controlling traffic exiting a domain by assigning the traffic to the best egress points (i.e. routers or links).. The general problem formulation of outbound TE is: given the network topology, BGP routing information and inter-domain Traffic Matrix (TM), determine the best Egress Point (EP) for each traffic demand so as to optimize the overall network performance [2]. Since inter-domain links are the most common bottlenecks in the Internet [2], optimizing their resource utilization becomes a key objective of outbound TE.In practice, network conditions change dynamically, which can make the current outbound TE solutions obsolete and subsequently cause some inter-domain links to become congested over time. One such dynamic change is inter-domain traffic variation, which is typically caused by changes in user or application behavior, adaptations from the TCP congestion control or even routing changes from other domains [5]. In addition to these traffic variations, transient and non-transient inter-domain peering link failures might occur. According to [7] transient inter-domain link failures are common events and their duration is less than a few minutes. Upon failure on a peering link, there may be a large amount of traffic shifted to other available EPs, potentially leading to congestion on these new serving EPs if they are not carefully chosen. In theory, although it is possible to perform outbound TE based on the other proposals in the literature [2,3,4] whenever any of those changes occur, it may require huge computational overheads and a large number of EP reconfigurations given that previous proposals have not considered the reduction of reconfiguration changes and overheads. This can lead to excessive service disruptions and is not practical. As a consequence, lack of TE solutions that react to those dynamic changes rapidly will leave the network unmanaged. It is thus the focus of this paper to make outbound TE more adaptive to fast-changing IP networks by taking into consideration practical network operation and management constraints such as time-efficiency, reconfiguration overheads and service disruptions.In this paper, we pro...