Use of DPI technology for server congestion control and reduction of power consumption by servers

Deep packet inspection (DPI) technology has conventionally been introduced for traffic monitoring, bandwidth control, bandwidth allocation, access control of specific types of traffic, etc. By installing a DPI equipment at any arbitrary point in a network, it is possible to monitor communications of many servers simply and this could simplify dramatically the conventional work load for system management and reduction of power consumption by servers. As a new potential application of DPI technology, this paper explores the possibility of applying DPI technology to server congestion control and reduction of power consumption by servers, and presents implementation examples of these applications. This paper first proposes an example of server congestion control method, in which the DPI equipment estimates the CPU usage of each server by constantly monitoring the number of live TCP connections established by each server, and moves some of virtual machines on the congested server to other servers through remote control timely. Next, this paper proposes an example of reducing power consumption by servers, in which the DPI equipment constantly monitors the traffic sent or received in each area with multiple servers. Finally, the feasibility of the proposed methods is demonstrated by an evaluation system with a real DPI equipment.