Application Layer

The Application Layer is the seventh level of the seven-layer OSI model, and the top layer of the TCP/IP model. It interfaces directly to and performs common application services for the application processes; it also issues requests to the Presentation Layer (OSI).

The common application layer services provide semantic conversion between associated application processes. Note: Examples of common application services of general interest include the virtual file, virtual terminal, and job transfer and manipulation protocols.

The application layer of the TCP/IP model corresponds to the entire group of application layer, Presentation Layer, and Session Layer in the seven layer OSI model



Protocol examples

* 9P, Plan 9 from Bell Labs distributed file system protocol
* AFP, Apple Filing Protocol
* APPC, Advanced Program-to-Program Communication
* AMQP, Advanced Message Queuing Protocol
* Basenet
* BitTorrent
* Atom Publishing Protocol
* BOOTP, Bootstrap Protocol
* CFDP, Coherent File Distribution Protocol
* DDS, Data Distribution Service
* DHCP, Dynamic Host Configuration Protocol
* DeviceNet
* DNS, Domain Name System (Service) Protocol
* eDonkey
* ENRP, Endpoint Handlespace Redundancy Protocol
* FastTrack (KaZaa, Grokster, iMesh)
* Finger, User Information Protocol
* Freenet
* FTAM, File Transfer Access and Management
* FTP, File Transfer Protocol
* Gopher, Gopher protocol
* HL7, Health Level Seven
* HTTP, HyperText Transfer Protocol
* H.323, Packet-Based Multimedia Communications System
* IMAP, IMAP4, Internet Message Access Protocol (version 4)
* IRCP, Internet Relay Chat Protocol
* Kademlia
* LDAP, Lightweight Directory Access Protocol
* LPD, Line Printer Daemon Protocol
* MIME (S-MIME), Multipurpose Internet Mail Extensions and Secure MIME
* Modbus
* Netconf
* NFS, Network File System
* NIS, Network Information Service
* NNTP, Network News Transfer Protocol
* NTCIP, National Transportation Communications for Intelligent Transportation System Protocol
* NTP, Network Time Protocol
* OSCAR, AOL Instant Messenger Protocol
* PNRP, Peer Name Resolution Protocol
* POP, POP3, Post Office Protocol (version 3)
* Rlogin, Remote Login in UNIX Systems
* RTPS, Real Time Publish Subscribe
* RTSP, Real Time Streaming Protocol
* SAP, Session Announcement Protocol
* SDP, Session Description Protocol
* SIP, Session Initiation Protocol
* SLP, Service Location Protocol
* SMB, Server Message Block
* SMTP, Simple Mail Transfer Protocol
* SNMP Simple Network Management Protocol
* SNTP, Simple Network Time Protocol
* RDP, Remote Desktop Protocol
* SSH, Secure Shell
* TCAP, Transaction Capabilities Application Part
* TDS, Tabular Data Stream
* TELNET, Terminal Emulation Protocol of TCP/IP
* TFTP, Trivial File Transfer Protocol
* TSP, Time Stamp Protocol
* VTP, Virtual Terminal Protocol
* Waka, an HTTP replacement protocol
* Whois (and RWhois), Remote Directory Access Protocol
* WebDAV
* X.400, Message Handling Service Protocol
* X.500, Directory Access Protocol (DAP)
* XMPP, Extensible Messaging and Presence Protocol