Before you begin
Access the phone administration web page. See
Access the Phone Web Page, on page 92
Procedure
Step 1
Select
Voice
>
Ext(n)
.
Step 2
Set up the fields as described in
Step 3
Click
Submit All Changes
.
NAT Mapping with Session Border Controller
We recommend that you choose an service provider that supports NAT mapping through a Session Border
Controller. With NAT mapping provided by the service provider, you have more choices in selecting a router.
NAT Mapping with SIP-ALG Router
NAT mapping can be achieved by using a router that has a SIP Application Layer Gateway (ALG). By using
a SIP-ALG router, you have more choices in selecting an service provider.
NAT Mapping with the Static IP Address
You can configure NAT mapping on the phone to ensure interoperability with the service provider.
• You must have an external (public) IP address that is static.
• The NAT mechanism used in the router must be symmetric. For more information, see
Symmetric or Asymmetric NAT, on page 74
.
Use NAT mapping only if the service provider network does not provide a Session Border Controller
functionality.
Before you begin
Access the phone administration web page. See
Access the Phone Web Page, on page 92
Procedure
Step 1
Select
Voice
>
SIP
.
Step 2
In the
NAT Support Parameters
section, set
Handle VIA received
,
Insert VIA received
,
Substitute VIA
Addr
,
Handle VIA rport
,
Insert VIA rport
, and
Send Resp To Src Port
fields to
Yes
.
Step 3
In the
NAT Support Parameters
section, set a value for the
NAT Keep Alive Intvl
field.
Step 4
Enter the public IP address for your router in the
EXT IP
field.
Step 5
Click the
Ext(n)
tab.
Step 6
In the
NAT Settings
section, set
NAT Mapping Enable
to
Yes
.
Step 7
(Optional) Set
NAT Keep Alive Enable
to
Yes
.
Cisco IP Phone 6800 Series Multiplatform Phones Administration Guide
72
Phone Installation
NAT Mapping with Session Border Controller
