Transport Layer Flow

Socket Connections

UDP Segment Structure

NTP Network Time Protocol –Uses port 123 UDP (User Datagram Protocol) Atomic Clock Synchronization Multiple Master Servers Used for –Distributed Databases –Client/Server –Security –Authentication

Clock Synchronization Time Server Time Client mt mr Tround = mt + mr time = t Clock set is t + Tround/2

Alternating bit protocol

Stop and Wait/Pipelined

Go-Back-N

Selective Repeat

SR Operation

SR windowing

TCP segment structure

TCP Segmentation

Sequence and Acknowledgement

Retransmission

Not Transmitted

Cumulative Acknowledgement

TCP Handshake

TCP Close

TCP sequences

Routing traffic

Multiple routers

TCP Slow Start

A Typical Wiring Closet Hubs & Switches - No routers

Transport Layer The End