P-2608HWL-Dx Series User’s Guide
Chapter 11 SIP
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11.1.7 NAT and SIP
The ZyXEL Device must register its public IP address with a SIP register server. If there is a
NAT router between the ZyXEL Device and the SIP register server, the ZyXEL Device
probably has a private IP address. The ZyXEL Device lists its IP address in the SIP message
that it sends to the SIP register server. NAT does not translate this IP address in the SIP
message. The SIP register server gets the ZyXEL Device’s IP address from inside the SIP
message and maps it to your SIP identity. If the ZyXEL Device has a private IP address listed
in the SIP message, the SIP server cannot map it to your SIP identity. See
for more information about NAT.
Use a SIP ALG (Application Layer Gateway), use NAT, STUN, or outbound proxy to allow
the ZyXEL Device to list its public IP address in the SIP messages.
11.1.7.1 SIP ALG
See
.
11.1.7.2 Use NAT
If you know the NAT router’s public IP address and SIP port number, you can use the Use
NAT feature to manually configure the ZyXEL Device to use them in the SIP messages. This
eliminates the need for STUN or a SIP ALG.
You must also configure the NAT router to forward traffic with this port number to the
ZyXEL Device.
11.1.7.3 STUN
STUN (Simple Traversal of User Datagram Protocol (UDP) through Network Address
Translators) allows the ZyXEL Device to find the presence and types of NAT routers and/or
firewalls between it and the public Internet. STUN also allows the ZyXEL Device to find the
public IP address that NAT assigned, so the ZyXEL Device can embed it in the SIP data
stream. STUN does not work with symmetric NAT routers or firewalls. See RFC 3489 for
details on STUN.
The following figure shows how STUN works.
1
The ZyXEL Device (A) sends SIP packets to the STUN server (B).
2
The STUN server (B) finds the public IP address and port number that the NAT router
used on the ZyXEL Device’s SIP packets and sends them to the ZyXEL Device.
3
The ZyXEL Device uses the public IP address and port number in the SIP packets that it
sends to the SIP server (C).
Summary of Contents for P-2608HWL-D1
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Page 32: ...P 2608HWL Dx Series User s Guide 32 List of Figures ...
Page 38: ...P 2608HWL Dx Series User s Guide 38 List of Tables ...
Page 44: ...P 2608HWL Dx Series User s Guide 44 Chapter 1 Getting To Know the ZyXEL Device ...
Page 66: ...P 2608HWL Dx Series User s Guide 66 Chapter 3 Internet and Wireless Setup Wizard ...
Page 72: ...P 2608HWL Dx Series User s Guide 72 Chapter 4 VoIP Wizard And Example ...
Page 78: ...P 2608HWL Dx Series User s Guide 78 Chapter 5 Bandwidth Management Wizard ...
Page 88: ...P 2608HWL Dx Series User s Guide 88 Chapter 6 Status Screens ...
Page 118: ...P 2608HWL Dx Series User s Guide 118 Chapter 8 LAN Setup ...
Page 138: ...P 2608HWL Dx Series User s Guide 138 Chapter 9 Wireless LAN ...
Page 166: ...P 2608HWL Dx Series User s Guide 166 Chapter 11 SIP ...
Page 176: ...P 2608HWL Dx Series User s Guide 176 Chapter 12 Phone ...
Page 184: ...P 2608HWL Dx Series User s Guide 184 Chapter 13 Phone Book ...
Page 220: ...P 2608HWL Dx Series User s Guide 220 Chapter 17 Content Filtering ...
Page 276: ...P 2608HWL Dx Series User s Guide 276 Chapter 20 Static Route ...
Page 288: ...P 2608HWL Dx Series User s Guide 288 Chapter 21 Bandwidth Management ...
Page 292: ...P 2608HWL Dx Series User s Guide 292 Chapter 22 Dynamic DNS Setup ...
Page 306: ...P 2608HWL Dx Series User s Guide 306 Chapter 23 Remote Management Configuration ...
Page 318: ...P 2608HWL Dx Series User s Guide 318 Chapter 24 Universal Plug and Play UPnP ...
Page 324: ...P 2608HWL Dx Series User s Guide 324 Chapter 25 System ...
Page 344: ...P 2608HWL Dx Series User s Guide 344 Chapter 27 Tools ...
Page 348: ...P 2608HWL Dx Series User s Guide 348 Chapter 28 Diagnostic ...
Page 360: ...P 2608HWL Dx Series User s Guide 360 Chapter 29 Troubleshooting ...
Page 378: ...P 2608HWL Dx Series User s Guide 378 Appendix B Setting up Your Computer s IP Address ...
Page 402: ...P 2608HWL Dx Series User s Guide 402 Appendix F Triangle Route ...
Page 440: ...P 2608HWL Dx Series User s Guide 440 Appendix H Internal SPTGEN ...