Use of Devolved Controllers in Data Center Networks
For data center network operators, this work offers a potential solution to the scalability bottleneck of centralized control, though it is a preliminary proof-of-concept without quantitative results.
The paper proposes using multiple independent controllers instead of a single centralized controller to manage resources in data center networks, addressing scalability issues. It demonstrates the feasibility of this approach through a proof-of-concept for flow allocation, showing that controllers can be configured to cover the entire network while each only manages a small portion.
In a data center network, for example, it is quite often to use controllers to manage resources in a centralized man- ner. Centralized control, however, imposes a scalability problem. In this paper, we investigate the use of multiple independent controllers instead of a single omniscient controller to manage resources. Each controller looks after a portion of the network only, but they together cover the whole network. This therefore solves the scalability problem. We use flow allocation as an example to see how this approach can manage the bandwidth use in a distributed manner. The focus is on how to assign components of a network to the controllers so that (1) each controller only need to look after a small part of the network but (2) there is at least one controller that can answer any request. We outline a way to configure the controllers to fulfill these requirements as a proof that the use of devolved controllers is possible. We also discuss several issues related to such implementation.