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Network Protocols

When it comes to communication among applications, all of it is done on either TCP or UDP or even both protocols. Both of these protocols are at Transport layer level (L4).

Basics of Protocols

TCP - Transport Control Protocol. Connection-oriented. Data delivery is guaranteed.

  • FTP [20/21] (File Transfer Protocol) -
  • TFTP [69] (Trivial File Transfer Protocol) - Does not ask for user-id pwd
  • SFTP [22] (Secure File Transfer Protocol) - Information is sent encrypted
  • SSH [22] (Secure Shell) - To connect to another computer in a secured way
  • Telnet [23] - To connect to another computer in unsecured way
  • SMTP [25/465] (Simple Mail Transfer Protocol) - Mail protocol. Mail server to mail server.
  • Second port is used when using secured connection with encryption TLS/SSL
  • IMAP4 [143/993] (Internet Message Access Protocol) - Mail protocol. Downloads a copy of message from the server
  • POP3 [110/995] (Post Office Protocol) - Mail protocol. Downloads original message from the server, deleting from the server.
  • HTTP [80] (Hypertext Transfer Protocol) -
  • HTTPS [443] (Hypertext Transfer Protocol Secure) - Uses SSL over HTTP

UDP - User Datagram Protocol. Connection-less. Data delivery is not guaranteed.

  • SNMP [161/162] (Simple Network Management Protocol) - Used to sends infrastructure operation information
  • NTP [123] (Network Time Protocol) - Server-sync is done over it
  • SIP [5060/5061] (Session Initiation Protocol) - Video and Voice
  • RTSP [554] (Real Time Streaming Protocol) - Stream media like YouTube or Hulu
  • DHCP [67/68] (Dynamic host Configuration Protocol) - Provides an IP address to a computer/hardware

Both (TCP and/or UDP)

  • LDAP [389] (Lightweight Directory Access Protocol) -
  • RDP [3389] (Remote Desktop Protocol) - Uses Windows.
  • DNS [53] (Domain Name System) -

List of Protocols

  • Ethernet Protocol - Link
  • IP - Internet
    • UDP - Transport
    • TCP - Transport
    • HTTP - Application
    • POP3 - Application

TLS (Transport Layer Security)

SSL (Secure Socket Layer)

Communication Protocols

  • P4
  • LDAP
  • Telnet
  • HTTP
  • RFC
  • JDBC
  • Session

API Protocols

  • SOAP
  • REST
  • JSON-RPC
  • gRPC
  • GraphQL
  • Thrift

IoT Protocols

  • MQTT
  • AMQP
  • REST
  • OPC UA
  • DHTP