An adaptive receiver-driven flow control mechanism in content-centric network

Abstract

Content-centric networking (CCN) is the newly designed network to mitigate the problems of the Internet such as the duplicated dissemination of contents. Since it is just started to redesign and reconstruct at the very beginning, every layers and protocols are required to define according to its characteristics. Flow control mechanisms in CCN are classified into two categories: receiver-driven and hop-by-hop. Receiver-driven flow control is driven by receiver side controlling the number of Interest messages requested to the network while hop-by-hop Interest shaping is controlled by CCN routers on the network regulating the data rate of each flow depending on the in/out link status. Because of the characteristics that a content is devided into small pieces of packets called chunks and CCN routers do not cache a whole of a content but a few chunks of the content, content is delivered by multiple content sources. Therefore, flow control mechanisms in CCN should address the problems caused by transitions of multiple content sources when it delivers a flow. If a flow is serviced by multiple content sources, there can be unexpected Interest timer expirations when a transition occurs caused by unstable RTTs. Or, a flow experiences relatively long time to approach an available data rate and to deliver content completely. Most of the previous receiver-driven flow control algorithms, however, do not address the fact that chunks are delivered by multiple content sources so they suffer from a performance degradation of content delivery caused by frequent Interest timer expirations. On the other flow control mechanism, hop-by-hop Interest shaping, may mitigate the problems by keeping the states of flows at each CCN router. However, keeping per-flow states is a burden to CCN routers and CCN suffers from the scalability issues and the deployment of the funtion in routers. Therefore, a pure receiver-driven flow control algorithm is required to be completely independent to the...