UDP:User Datagram Protocol [RFC 768] "no frills,""bare bones" Internet transport Why is there a UDP? protocol ▣no connection "best effort"service,UDP establishment (which can segments may be: add delay) o lost simple:no connection state o delivered out of order at sender,receiver to app ▣small segment header ▣connectionless: no congestion control:UDP o no handshaking between can blast away as fast as UDP sender,receiver desired o each UDP segment handled independently of others Transport Layer 3-16Transport Layer 3-16 UDP: User Datagram Protocol [RFC 768]  “no frills,” “bare bones” Internet transport protocol  “best effort” service, UDP segments may be:  lost  delivered out of order to app  connectionless:  no handshaking between UDP sender, receiver  each UDP segment handled independently of others Why is there a UDP?  no connection establishment (which can add delay)  simple: no connection state at sender, receiver  small segment header  no congestion control: UDP can blast away as fast as desired