3-15
Cisco SIP IP Phone Administrator Guide
Chapter 3 Managing Cisco SIP IP Phones
Modifying the Phone’s SIP Settings
image_version
Required
Firmware version that the Cisco SIP IP phone should run.
Enter the name of the image version (as it is released by
Cisco). Do not enter the extension. You cannot change
the image version by changing the file name, because the
version is also built into the file header. Trying to change
the image version by changing the file name causes the
firmware to fail when it compares the version in the
header against the file name.
logo_url
Optional
Location of the company logo file. This logo appears on
the phone display. The background space allocated for
the image is 90 x 56 pixels. Images that are larger than
this will automatically be scaled down to 90 x 56 pixels.
The recommended file size for the image is 5 to 15k.
For
example, use logo_url:
“http://10.10.10.10/companylogo.bmp”.
Note
This parameter supports Windows 256 color
bitmap format only. CMXML PhoneImage
objects are not supported for this parameter.
Using anything other than a Windows bitmap
(.bmp) file can cause unpredictable results.
messages_uri
Optional
Number to call to check voice mail. This number is
called when the Messages key is pressed.
nat_address
Optional
The WAN IP address of the Network Address Translation
(NAT) or firewall server. You can use either a dotted
IP address or a DNS name (A record only).
nat_enable
Optional
Use 0 to disable NAT and 1 to enable NAT. Default is 0.
When NAT is enabled, the Contact header appears like
this:
Contact:
sip:lineN_name@nat_address:voip_control_port
If nat_address is invalid or UNPROVISIONED, then the
Contact header appears like this:
Contact:
sip:lineN_name@phone_ip_address:voip_control_port
and the Via header appears like this:
Via: SIP/2.0/UDP
phone_ip_address:voip_control_port
If NAT is enabled, the Session Description Protocol
(SDP) message uses the nat_address and an RTP port
between the start_media_port and the end_media_port
range in the C and M fields. All RTP traffic is sourced
from the port advertised in the SDP.
Table 3-3
Default SIP Configuration File Parameters (continued)
Parameter
Required or
Optional
Description