
URGENT READ THIS BEFORE USING IP PHONE SOFTWARE 
-----------------------------------------------

Cisco IP Phone firmware images now contain a
Cisco digital signature to provide authentication for
improved security. Once firmware version 5.0 is
loaded onto a phone, all subsequent firmware
versions will be checked for authenticity.

Firmware images prior to release 5.0 do not contain
a Cisco digital signature and therefore once version
5.0 is loaded onto a phone, all prior firmware
releases will be rejected.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
! This means that you will NOT be able to downgrade the  !
! firmware to a release prior to 5.0 once 5.0 or greater !
! is installed onto a phone.                             !  
!                                                        !
! Cisco recommends the following procedure               ! 
! for upgrading to release 5.2                           !
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Upgrading to Release 5.2
When you upgrade to Release 5.2, you will download 
a ZIP archive instead of a firmware image file as in earlier releases. 
Contained in the archive are the unsigned (.bin) and signed (.sbn) binary 
images. 

Release 5.2
Release 5.2 is a maintenance release follow up to Release 5.1.
The following issues have been addressed in Release 5.2:

SIP Issues
----------
Phone removes dots in the IP address when sending ACK

MGCP Issues
-----------
phone reboots after failure with external transfer
Parser does not handle global and specific c lines

Platform Issues
---------------
Memory leak issues related to DNS query failures
Phone crashes upon any menu exit
DSP mismatch with upgrade failure

 

Procedure
--------------------------------------------------------------------------------
Step 1   Unzip the ZIP archive to extract the binary images and any notes or 
         readme text files. Read these text files for any special directions 
         regarding the images.

Step 2   Copy the new images P0S3-xx-y-zz.sbn (signed binary) and P0S3-xx-y-zz.bin 
         (unsigned binary), where xx is the release major version, y is the release 
         minor version, and zz is the maintenance number, to the root directory 
         of the TFTP server.

Step 3   Using a text editor, open the configuration file and update the image version 
         specified in the image_version variable. The version name in the image_version 
         variable should match the version name (without the .sbn extension) of the 
         latest firmware that you downloaded (for example, P0S3-xx-y-zz).

Step 4   Reset each phone.

The phone contacts the TFTP server and requests its configuration files. The phone 
compares the image defined in the file to the image that it has stored in Flash memory. 
If the phone determines that the image defined in the file differs from the image in 
Flash memory, it downloads the image defined in the configuration file (which is stored 
in the root directory on the TFTP server). Once the new image has been downloaded, the 
phone programs that image into Flash memory and then reboots. 


For additional release 5.2 information
see the admin guides and release notes located:

SIP:
http://www.cisco.com/univercd/cc/td/doc/product/
voice/c_ipphon/english/ipp7960/addprot/sip/index.htm

MGCP:
http://www.cisco.com/univercd/cc/td/doc/product/
voice/c_ipphon/english/ipp7960/addprot/mgcp/index.htm

