Skip to content

Application Layer

  • use
    • provide service to user
    • software generate the data
  • protocols
    • Telnet/SSH
    • FTP/SFTP/SCP
    • SMTP/POP3/IMAP
    • HTTP/HTTPS
    • BGP
    • DNS
    • SNMP
    • NetBIOS
    • NTP
    • WINS
    • RIP/RIP2/RIPRng
  • pdu
    • data
  • use
    • format of the data
    • compression and decompression
    • encrypt and decrypt data
    • for translation,encryption ,compression
  • pdu
    • data
  • use
    • maintain the session via port numbers
    • like same website on different tabs on browser
    • or different application
    • data will not get intermixed
    • used to manage , establish ,terminate session
    • it allows the communication between two processes which can be either half-duplex or full-duplex.
    • adds some checkpoints when transmitting the data in a sequence.
    • Synchronization and recovery process - if error occurs in middle of transmission, then the transmission will resume from the checkpoint.
  • pdu
    • data

HTTP/HTTPS