Research On Key Techniques Of Load Balancing In Datacenter Networks

Datacenters is the information infrastructure in modern society.In order to avoid the network congestion and reduce the end-to-end latency in datacenter networks,load balancing schemes are necessary to be deployed to distribute traffic evenly.At present,researchers have proposed many load balancing schemes in datacenter networks.However,due to the expensive cost of upgrading datacenter switches and the difficulty in verifying their performance in large-scale datacenter networks,most of them have not been deployed in practice.In order to make full use of existing network resources,this paper focuses on the research of the key techniques of datacenter networks load balancing.The main contributions are as follows:Firstly,for the datacenter networks constructed by traditional datacenter switches,this paper proposes the load balancing scheme for datacenter networks based on centralized routing optimization,CO-BGP.CO-BGP coordinates with the distributed routing protocol BGP(Border Gateway Protocol),and achieves load balancing by switching routes.It is a complete load balancing solution in datacenter networks,which consists of the functions of collecting network status,making decisions of routing optimization and configuring routes on switches.Aiming at the difficulty that traditional datacenter switches cannot collect flow-granularity statistics,which results in CO-BGP cannot precisely reroute traffic,this paper proposes a rerouting scheme based on the Bayes learning technique.Experimental results show that CO-BGP can be easily deployed in existing datacenter networks,and has a good effect in reducing network congestion and achieving load balancing.Secondly,for the datacenter networks constructed by traditional datacenter switches,this paper proposes load balancing scheme for datacenter networks based on cutting network prefix.The scheme can be deployed in the control plane of the datacenter switches and automatically cutting the prefixes of the destination networks to realize multi-path forwarding and load balancing,and the process of cutting prefixes is transparent to the routing protocol and data plane of the datacenter switches.the scheme solves the hard problem that the forwarding function is solidified into the ASIC chips and do not support customized multi-path forwarding schemes.Theoretical analysis and experiments have verified that this scheme can be applied to the existing datacenter networks and has good effects in reducing the flow completion time and realizing load balancing.Thirdly,for the datacenter networks constructed by programmable datacenter switches,this paper proposes a global and local integrated load balancing scheme,GLIB for datacenter networks.GLIB overcomes the shortcomings that the existing load balancing schemes cannot take into account both the global view and local view,and organically combines the global and local load balancing schemes for the first time.Aiming at the conflict of decision space between global and local load balancing schemes,this paper proposes a local load balancing scheme based on primary-backup paths and a centralized global load balancing scheme,which cooperate with each other to deal with the burst traffic and load imbalance traffic.This paper also proposes a global route initialization algorithm for calculating the optimal routes when the network is initialized or the topology changes.Experiments have verified that GLIB has a good effect in reducing flow completion time and the tail latency.