Interactive transparent networking-modeling examples of snoop and WTCP protocols

The layered rigid organization of traditional network service stack currently poses several problems in service evolution and versatility. The 'Programmable' and 'Active' network paradigms offer to solve such problems by allowing arbitrary custom codes to be embedded inside network layers. We propose a less radical approach in which required service state information can be pulled-up to the upper layer where 'actions' are performed by programmable components, and generated 'actions' are pushed down into the network layer. This approach relives lower network layers from housing costly custom components and addresses other practical issues like security and flexibility. We call this mechanism 'Interactive Transparent Networking'. In this paper, we explain the mechanism and its advantages in creating TCP-friendly applications. We also show by example how it can be used as a protocol augmentation tool by modeling two well-known protocols proposed in the literature to improve TCP performance over wireless networks: Snoop [H. Balakrishnan, S. Seshan, and R. Katz, Improving reliable transport and handoff performance in cellular wireless networks, ACM Wireless Networks 1 (1995)] and WTCP [P. Sinha, N. Venkitaraman, R. Sivakumar, V. Bharghavan, WTCP: a reliable transport protocol for wireless wide-area networks, Proceedings of ACM Mobicom'99, Seattle, WA, pp. 231-241].