Network edge:connectionless service Goal:data transfer App's using TCP: between end systems ▣HTTP(Web),FTP(file same as before! transfer),Telnet 口UDP-User Datagram (remote login),SMTP Protocol [RFC 768]: (email) connectionless *unreliable data App's using UDP: transfer 口streaming media, no flow control teleconferencing,DNS, *no congestion control Internet telephony Introduction 1-14Introduction 1-14 Network edge: connectionless service Goal: data transfer between end systems ❖ same as before! ❑ UDP - User Datagram Protocol [RFC 768]: ❖ connectionless ❖ unreliable data transfer ❖ no flow control ❖ no congestion control App’s using TCP: ❑ HTTP (Web), FTP (file transfer), Telnet (remote login), SMTP (email) App’s using UDP: ❑ streaming media, teleconferencing, DNS, Internet telephony