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300-820 · Question #85

Which protocol should be used to verify the connectivity for different media paths found during a call using ICE?

The correct answer is A. STUN. STUN (Session Traversal Utilities for NAT), defined in RFC 5389, is the protocol used within the ICE process to perform connectivity checks on candidate pairs. After ICE gathers all candidate addresses, it sends STUN Binding Requests along each candidate pair path. A successful…

Key Concepts

Question

Which protocol should be used to verify the connectivity for different media paths found during a call using ICE?

Options

  • ASTUN
  • BRTP
  • CSNMP
  • DTURN

How the community answered

(65 responses)
  • A
    86% (56)
  • B
    8% (5)
  • C
    2% (1)
  • D
    5% (3)

Explanation

STUN (Session Traversal Utilities for NAT), defined in RFC 5389, is the protocol used within the ICE process to perform connectivity checks on candidate pairs. After ICE gathers all candidate addresses, it sends STUN Binding Requests along each candidate pair path. A successful STUN Binding Response confirms that the path is reachable and also reveals the externally-mapped (server-reflexive) address, allowing NAT bindings to be discovered. TURN (D) is used to relay media through a TURN server when direct paths fail-it is a fallback, not the verification mechanism. RTP (B) carries media after a path is selected. SNMP (C) is unrelated to call media path establishment.

Topics

#ICE#STUN#NAT Traversal#Media Connectivity

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