Cisco Cisco IOS Software Release 12.0(27)S

Software images for Cisco 12000 series Internet routers have been deferred to Cisco IOS Release 
12.0(27)S1.

Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image 
support. Access Cisco Feature Navigator at 

. You must have an account on 

Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at 
the login dialog box and follow the instructions that appear. 

12.0(26)S

The following new features were introduced:

Support for connecting disparate attachment circuits. See L2VPN Interworking 
for more information. 

QoS functionality with AToM for the Cisco 7200 series routers.

Support for FECN and BECN marking with Frame Relay over MPLS. (See 
BECN and FECN Marking for Frame Relay over MPLS for more information.)

12.0(27)S

The following new features were introduced:

ATM Cell Relay over MPLS: Packed Cell Relay for VC, VP, and port mode for 
the Cisco 12000 series router.

Support for ATM over MPLS on the Cisco 12000 series 4-Port OC-12X/STM-4 
ATM ISE line card. 

Cisco 7200 series, Cisco 7500 series, Cisco 12000 series, Cisco 10720 Internet router

See the sections that describe the features to determine the platforms that support the features. 

See 

 for the supported port adapters and line cards.