1. 1 Declarative Transport A Customizable Transport Service for the Future Internet Karim Mattar Ibrahim Matta John Day Vatche Ishakian Gonca Gursun Department of Computer Science Boston University

2. 2 A Quote TCP is a kludge and it is one heck of a thesis generator! -- John Day

3. 3 A Question What is inherently so difficult about designing transport solutions?

4. 4 Current Internet Architecture is Misleading Application Transport Network Link Physical Application Transport Network Link Physical Let us consider an alternate organizing structure…

5. 5 Recursive Internet Architecture (RINA) J. Day, I. Matta, and K. Mattar. Networking is IPC: A Guiding Principle to a Better Internet. In Re-Architecting the Internet (ReArch), December 2008. End Host Router

6. 6 Functions within a RINA Layer

7. 7 Key Insight from RINA Transport is a service provided by all nodes in the network to support applications. Transport state is distributed. It can be collected, stored, manipulated and queried by all nodes.

8. 8 Quick Questions What is transport state? Isn’t that a lot of state to be maintained by the nodes in the network?

9. 9 Recursive Internet Architecture (RINA) J. Day, I. Matta, and K. Mattar. Networking is IPC: A Guiding Principle to a Better Internet. In Re-Architecting the Internet (ReArch), December 2008. ISP-wide DIF

10. 10 Decomposing Transport Solutions Transport Packet Info that is independent from the user’s data (e.g., win size, rtt estimate) Info that must be sent with the user’s data (e.g., checksum, seqnum)

11. 11 Decomposing Transport Solutions Data Transfer Protocol (DTP) Transport Data Transfer Control Protocol (DTCP) Management Protocol This is independent from any implementation Only transport control and management information need to be manipulated declaratively

12. 12 P2 System and NDLog T. Condie, J. Hellerstein, P. Maniatis, S. Rhea, and T. Roscoe. Finally, a Use for Componentized Transport Protocols. In HotNets-IV, November 2005.

13. 13 Transport Policies in P2 Source Destination Seqnums Sent 11 12 13 10 Sack{11,13} Selective Acks

14. 14 Transport Policies in P2 Source Destination Seqnums Sent 12 13 10 11 Cumulative Acks CumAck{12}

15. 15 Transport Policies in P2 Source Destination Ack Regulator Mun Choon Chan and Ramachandran Ramjee. TCP/IP Performance over 3G Wireless Links with Rate and Delay Variation. In ACM MOBICOM, September 2002. Seqnums Sent 12 13 10 11 Acks Sent 10 Smart Acks Cellular Channel CumAck{12} CumAck{10}

16. 16 Transport Policies in P2 Source Destination Local Retransmission H. Balakrishnan, S. Seshan, E. Amir, and R. H. Katz. Improving TCP/IP Performance over Wireless Networks. In ACM MOBICOM, November 1995. Seqnums Sent 12 13 10 11 Seqnums Sent 12 13 10 11 Local Retransmission CumAck{12} Pkt{13}

17. 17 5 Transport Policies in P2 Source Destination N. Riga, I. Matta, A. Medina, C. Partridge, and J. Redi. JTP: An Energy-conscious Transport Protocol for Multi-hop Wireless Networks. In CoNEXT, December 2007. Min BW 10 Rate Control minBW Min BW 5 8 Rate 14

18. 18 Transport Policies in P2 A R4R4 R3R3 R2R2 R1R1 Source J. Byers, G. Kwon, M. Luby, and M. Mitzenmacher. Fine-grained Layered multicast with STAIR. IEEE/ACM Trans. Netw., 14(1):81-93, 2006. Multicast B S Receiver (b) Receiver (b+e) Streams b b+e Streams b+e b

19. 19 Final Thoughts Extensions to NDLog: (1) support for timers (2) support for transactions Some open problems: (1) trade-off between maintaining state at the nodes or passing it in headers (2) selection of optimal locations for maintaining transport state