Linksys Voice System Administration Guide
41
Network Address Translation (NAT) and Voice over IP (VoIP)
Configuring the SPA9000 for ITSP Interoperability
NAT Mapping with Session Border Controller
It is strongly recommended that you choose an ITSP that supports NAT mapping through a
Session Border Controller (see
Figure 3-3
). With NAT mapping provided by the ITSP, you have
more choices in selecting a router.
Figure 3-3 NAT Support with Session Border Controller Provided by ITSP
Configuring NAT Mapping with a Static IP Address
Configuring NAT mapping in the SPA9000 is recommended only if the ITSP network does not
provide a Session Border Controller functionality. In this case, and if the external (public) IP
address is static, then it is recommended to perform a static (permanent) mapping on SPA9000.
This setting is also recommended if NAT mechanism used in the router is symmetric.
Note
The LAN switch needs to be configured to enable Spanning Tree
Protocol and Port Fast on the ports to which the SPA9000 and the
SPA9xx phones are connected.
1. Connect to the SPA9000 administration web server, and choose Admin access with
Advanced settings. (See
”Connecting to the SPA9000 Administration Web Server,” on
page 24
.)
2. Click
Voice tab > SIP
.
3. Scroll down to the
NAT Support Parameters
section, and then enter the following settings to
support static mapping to your public IP address:
•
Handle VIA received, Insert VIA received, Substitute VIA Addr:
yes
•
Handle VIA rport, Insert VIA rport, Send Resp To Src Port:
yes
•
EXT IP:
Enter the public IP address for your router.
SIP Proxy
Internet
ITSP
NAT Device
SPA9000
192.168.1.102
ISP
DHCP
server
192.168.1.101
192.168.1.100
Session Border
Controller
Private IP address
192.168.1.1
External IP address
assigned by ISP
Router and
DHCP Server
Summary of Contents for Linksys SPA9000
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