Nat And Sip; Diffserv - ZyXEL Communications MAX-207HW2 User Manual

Chapter 10 The Service Configuration Screens
Client device A then sends the call invitation to client device C.
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Figure 50 SIP Redirect Server
A

10.4.6 NAT and SIP

The WiMAX Modem must register its public IP address with a SIP register server. If
there is a NAT router between the WiMAX Modem and the SIP register server, the
WiMAX Modem probably has a private IP address. The WiMAX Modem 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
WiMAX Modem's IP address from inside the SIP message and maps it to your SIP
identity. If the WiMAX Modem has a private IP address listed in the SIP message,
the SIP server cannot map it to your SIP identity. See
Configuration Screens
Use a SIP ALG (Application Layer Gateway), Use NAT, STUN, or outbound proxy to
allow the WiMAX Modem to list its public IP address in the SIP messages.

10.4.7 DiffServ

DiffServ is a class of service (CoS) model that marks packets so that they receive
specific per-hop treatment at DiffServ-compliant network devices along the route
based on the application types and traffic flow. Packets are marked with DiffServ
Code Points (DSCPs) indicating the level of service desired. This allows the
intermediary DiffServ-compliant network devices to handle the packets differently
depending on the code points without the need to negotiate paths or remember
state information for every flow. In addition, applications do not have to request a
particular service or give advanced notice of where the traffic is going.
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for more information.
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Chapter 8 The NAT
User's Guide