Simulation and Evaluation of Load-Adaptive Traffic Engineering
Protocols on Overlay Networks
(Simulation und Evaluierung lastadaptiver Traffic Engineering
Protokolle auf Overlay-Netzwerken)
One major issue in computer networking is to balance load evenly among the available resources. Methods for actively balancing the load by reassigning it to the network resources according to the current traffic situation are generally referred to as traffic engineering. Current traffic engineering protocols operate on the time scale of several hours which is too slow to react to realistic bursty traffic.
On the other hand, recent theoretical results show that flow can be assigned evenly among a network in a distributed fashion quickly by applying a simple and selfish improvement policy locally. There is also experimental evidence showing that this policy when applied as a rerouting protocol improves the throughput of the network. The protocol proceeds by meauring the link utilisation of adjacent links, transmits aggregated information for every route to neighbouring routers, and in turn receives information from its own neighbours. Based on this information the routers shift traffic carefully from overloaded to underloaded routes. This protocol, however, requires routers to cooperate. It is therefore only effective if implemented by a larger set of routers which presents a major obstacle in deploying such protocols. Hence, two questions arise:
- Can we implement a similar protocol that does not rely on communication between routers? This would make it necessary to gather more data at the individual routers.
- Can this protocol be applied in settings where end hosts are in control of the routing? This would allow for an easier deployment of the protcol in practice. Such settings include Peer-To-Peer or, more generally, overlay networks.
A Java implementation of the routing protocol on router level exists for the Scalable Simulation Framework (SSFNet). The idea is now to add implementations of similar routing protocols for P2P applications and evaluate their performance by means of simulation. This also has the perspective of being implemented in one of the open-source P2P systems.
Requirements: The diploma student should have good knowledge of network protocols and algorithms from either a theoretical or practical perspective. Good programming skills in Java and the ability to find your way through a complex simulation framework are a necessity.
Kontakt: Berthold Vöcking oder Simon Fischer