Intelligent Application Switch Supporting TCP

Recent programmable switches allow developers to profoundly optimize network elements. In this paper, we introduce a concept of an application switch that supports a network application based on programmable switches. A developer can optimize not only server computers but also network switches in order to improve application performance by implementing part of functions of the network application with an application switch. We then propose a method to apply an application switch for a database management system (DBMS) using TCP. The method migrates a TCP connection from a server computer to the application switch when the switch replies a query. The method reversely migrates it to the server computer again when a query is processed by the server. The application switch manages the TCP sequence number and the Ack number for these migrations. We constructed key-value store (KVS), which is one of DBMSs, using Cassandra and evaluated our method. Our evaluation showed that the proposed method improved the performance by 69% at most.