Adaptive Link Rate Switching Based on Traffic Splitting Method for Power Saving
Shingo Uchida, Shigetomo Kimura · 2020
In recent years, power consumption from network devices has increased as Internet traffic has grown. In order to address this problem, many researchers have proposed schemes that switch the link rate for OpenFlow networks. For example, we previously proposed a method based on the adaptive link rate switching concept which switches between high and low rates based on the usage of the link. Furthermore, the method provided a middle rate, which is constructed from multiple low rate links but consumes less power than that of a high rate link. It showed that power consumption can be reduced from that of simple adaptive link rate switching, but provided only for communications over MPTCP (Multipath TCP). To provide the method for other protocols such as TCP and UDP, this paper proposes a new adaptive link rate switching method based on traffic splitting, which uses OpenFlow meter tables. The meter tables measure traffic speeds and can change the DSCP (Differentiated Services Code Point) field in IP headers if the speeds exceed a pre-defined value such as a link bandwidth. The traffic splitting method assigns a different route for each DSCP value depending on the traffic volume, so dividing a traffic flow into multiple routes. On dividing a traffic flow, the proposed method switches the adaptive link rate from the low rate to the middle rate. When the traffic speed exceeds the middle rate, the proposed method also switches the rate of the shortest link to the high rate and aggregates all divided links onto the high rate link. The paper verifies the feasibility of the proposed method on an emulated network and also calculates the power consumption reduction over a typical traffic pattern to show that power consumption may be reduced from that of a simple adaptive link rate.