CS536-2009-02-19

CS536-2009-02-19 - CS536: Transport Layer Charles Killian...

Info iconThis preview shows pages 1–12. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: CS536: Transport Layer Charles Killian Slides used from Kurose-Ross, Computer Networking, a Top Down Approach Transport Layer 1 Announcements Programming assignment 1 (2/28, 11:59pm) Rescheduled class (April 21,23) Wednesday, April 15 th , 6-9pm, BRNG B222 Reading assignment TCP Vegas: Due 2/24 XCP: Due 3/3 Mid-term (Thursday, March 12 th , in class) Let me know if you must schedule a make-up. Transport Layer 2 Recap Fast-retransmit 3-way handshaking Cumulative acks Byte ranges, not packet numbers Initial sequence numbers Delayed acking RTT estimation (and timeout computation) Transport Layer 3-3 Transport Layer 3-4 Transport Layer 3-5 TCP Connection Management (cont) TCP client lifecycle TCP server lifecycle Transport Layer 3-6 Transport Layer 3-7 Chapter 3 outline 3.1 Transport-layer services 3.2 Multiplexing and demultiplexing 3.3 Connectionless transport: UDP 3.4 Principles of reliable data transfer 3.5 Connection-oriented transport: TCP segment structure reliable data transfer flow control connection management 3.6 Principles of congestion control 3.7 TCP congestion control Transport Layer 3-8 Principles of Congestion Control Congestion: informally: too many sources sending too much data too fast for network to handle different from flow control! manifestations: lost packets (buffer overflow at routers) long delays (queueing in router buffers) a top-10 problem! Transport Layer 3-9 Causes/costs of congestion: scenario 1 two senders, two receivers one router, infinite buffers no retransmission large delays when congested maximum achievable throughput unlimited shared output link buffers Host A in : original data Host B out Transport Layer 3-10 Causes/costs of congestion: scenario 2 one router, finite buffers sender retransmission of lost packet finite shared output link buffers Host A in : original data Host B out ' in : original data, plus retransmitted data Transport Layer 3-11 Causes/costs of congestion: scenario 2 always: (goodput) perfect retransmission only when loss: retransmission of delayed (not lost) packet makes larger (than perfect case) for same in out = in out > in out costs of congestion: more work (retrans) for given goodput unneeded retransmissions: link carries multiple copies of pkt R/2 R/2 in out b....
View Full Document

Page1 / 31

CS536-2009-02-19 - CS536: Transport Layer Charles Killian...

This preview shows document pages 1 - 12. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online