UDP

User Datagram Protocol

• Designed in conjunction with IP
• Interface to services
  • If I want to allow an IPsec negotiation we have to use IKE
  • Executable running in memory waiting for our commands
• Unreliable delivery
  • In real time applications we use unreliable delivery
  • It is what UDP is built for.
  • Has less overhead than a TCP would have.

Use Cases

• Domain name queries
• Realtime audio applications
• Realtime video applications
• Simple transfers
  • FTP
    • It's clear text
    • Requires authentication
  • TFTP
    • File repository that you can easily read and write for.
    • Send a query and it doesn't care who you are so you are granted access.
    • VoIP
• Polling
  • Simple Network Management Protocol (SNMP)
    • Query the device for:
      • CPU %, MEM %, Storage %, INT0, INT1
      • How are your resources? how do we check that? By polling
    • The more often you polling the best but the more often you poll the greater the bandwidth.
    • Clients want to see performance.
• Multicast
  • Typically for streaming video and audio

UDP Header Diagram