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Supported NAT and SIP Standards

The Junos OS substantially supports the following Network Address Translation (NAT) and Session Initiaion Protocol (SIP) standards. NAT supports SIP dialogs and UDP/IP version 4 (IPv4) transport of SIP messages.


This is applied to Junos routers equipped with one or more Adaptive Services PICs (both standalone and integrated versions), Multiservices PICs or DPCs, and services cards (SPC) of a security device (i.e. SRX).

Junos OS substantially supports the following RFC and Internet draft.

  • RFC 3261, SIP: Session Initiation Protocol

  • Internet draft draft-mrw-behave-nat66-01.txt, IPv6-to-IPv6 Network Address Translation (NAT66)

The following RFCs do not define standards, but provide information about NAT. The IETF classifies them variously as “Best Current Practice,” “Historic,” or “Informational.”

  • RFC 1631, The IP Network Address Translator (NAT)

  • RFC 2663, IP Network Address Translator (NAT) Terminology and Considerations

  • RFC 2766, Network Address Translation - Protocol Translation (NAT-PT)

  • RFC 2993, Architectural Implications of NAT

  • RFC 3022, Traditional IP Network Address Translator (Traditional NAT)

  • RFC 4787, Network Address Translation (NAT) Behavioral Requirements for Unicast UDP

  • RFC 5382, NAT Behavioral Requirements for TCP

  • RFC 5508, NAT Behavioral Requirements for ICMP