TCP Incast in Data Center Networks: Issue and Existing Solutions

Abstract

Data centers networks supports heterogeneous kind of applications like social networking, e-commerce, web search, video data hosting, computation-intensive and data-storage. It has high-bandwidth links, low propagation delay and commodity switches with small-size buffers. Under cluster-based storage environment, data center supports barrier-synchronized many-to-one communication pattern where multiple worker nodes simultaneously transmit bulk of data to single aggregator node by running standard TCP protocol. This synchronized transmission may overload aggregator’s switch buffer, which leads to severe packet loss and overall throughput fall. This is called as TCP Incast problem. This paper analyses issue of TCP Incast and provides detailed survey about several solutions at link, transport and application layer to mitigate impact of TCP Incast in data center network. Solutions are described with their procedural approach for alleviating Incast. Comparative evaluation between these solutions provides understanding about their merits, demerits and applicability under various implementation circumstances.