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Declarative TransportA Customizable Transport Service for the Future Internet

Karim MattarIbrahim Matta

John DayVatche IshakianGonca Gursun

Department of Computer ScienceBoston University

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A Quote

TCP is a kludge and it is one heck of a thesis generator!

-- John Day

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A Question

What is inherently so difficult about designing transport solutions?

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Current Internet Architecture is Misleading

ApplicationTransport

Network

LinkPhysical

ApplicationTransport

Network

LinkPhysical

Let us consider an alternate organizing structure…

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Recursive Internet Architecture (RINA)

BA C N-level DI F

(N-1)-level DI Fs

shared state

applicationprocesses

I PC process(sender/ receiver)

I PC process(sender/ receiver)

I PC process(sender/ receiver/ proxy)

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 End HostRouter

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Functions within a RINA Layer

routing, monitoring,resource allocation, access control, etc.

I PC

Transfer

I PCControl I PC Management

Delimiting

Transfer

Relaying/ Muxing

PDU Protection

DTSV RI B

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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.

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Quick Questions

What is transport state?

Isn’t that a lot of state to be maintained by the nodes in the network?

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Recursive Internet Architecture (RINA)

BA C N-level DI F

(N-1)-level DI Fs

shared state

applicationprocesses

I PC process(sender/ receiver)

I PC process(sender/ receiver)

I PC process(sender/ receiver/ proxy)

borderrouters

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

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Decomposing Transport Solutions

Transport Packet

Info that is independent from the user’s data

(e.g., win size, rtt estimate)

Info that must be sentwith the user’s data

(e.g., checksum, seqnum)

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Decomposing Transport Solutions

Data TransferProtocol

(DTP)Transport

Data TransferControl Protocol

(DTCP)

ManagementProtocol

This is independent from any implementation

Only transport control and management information need to be manipulated declaratively

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P2 System and NDLog

MUX

Queue

UDP Rx

CC Rx

ACK

Demux

Rule strands specifying protocol behavior

Join Project Aggregate

Join Select Project

Relation A Relation CRelation B

Queue

Retry

CC Tx

UDP Tx

Demux

Local

Remote

Net

wo

rk In

Netw

ork O

ut

Insert Insert Insert

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

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Transport Policies in P2

Source Destination

Seqnums Sent

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1213

10

Sack{11,13}

Selective Acks

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Transport Policies in P2

Source Destination

Seqnums Sent

1213

10

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Cumulative Acks

CumAck{12}

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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

1213

10

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Acks Sent10

Smart Acks

Cellular Channel

CumAck{12}

CumAck{10}

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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

1213

10

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Seqnums Sent

1213

10

11

Local Retransmission

CumAck{12}

Pkt{13}

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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 BW10

Rate Control

minBW

Min BW5

Min BW8

Rate14

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Transport Policies in P2

A

R4

R3

R2

R1

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)

Receiver (b)

Receiver (b+e)

Streamsb

Streamsb+e

Streamsb+eb

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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