Installation guide

21
Release Notes for Cisco uBR7200 Series for Cisco IOS Release 12.1 T
78-10643-04 Rev. B0
New and Changed Information
objects, including an NTP server peers table and an NTP server filter register table. For complete details
on the Cisco implementation of the NTP MIB, see the MIB file itself at
ftp://ftp.cisco.com/pub/mibs/v2/CISCO-NTP-MIB.my.
Parser Cache
The Parser Cache feature optimizes the parsing (translation) of Cisco IOS software configuration
command lines by remembering how to parse recently encountered command lines. This feature was
developed to improve the scalability of the Cisco IOS software command-line interface (CLI) parser
when processing large configuration files. This improvement is especially useful for those cases in
which thousands of virtual circuits must be configured for interfaces, or hundreds of access control lists
(ACLs) are required. The parser chain cache can rapidly recognize and translate configuration lines that
differ slightly from previously used configuration lines (for example, pvc 0/100, pvc 0/101, and so on).
Testing indicates an improvement to load time of between 30% and 36% for large configuration files
when using the parser cache.
The parser cache is enabled by default on all platforms using Cisco IOS Release 12.1(5)T or later. A
new global configuration command, [no] parser cache, allows the disabling or reenabling of this
feature.
PIM Dense Mode State Refresh
The PIM Dense Mode State Refresh feature keeps the pruned state in PIM dense mode from timing out
by periodically forwarding a control message down the source-based distribution tree. The control
message refreshes the prune state on the outgoing interfaces of each router in the distribution tree.
PPPoE Termination on Cable interfaces
The PPPoE on Cable Interfaces feature adds support for PPPoE by allowing a direct connection to cable
interfaces. PPPoE provides service-provider digital-subscriber line (DSL) support. The support of
PPPoE on cable interfaces of the Cisco uBR7200 series routers allows customer premises equipment
(CPE) behind the cable modem to use PPP as a mechanism to get their IP addresses and use it for all
subsequent data traffic, just like a dial-up PPP client. In a PPP dial-up session, the PPPoE session is
authenticated and the IP address is negotiated between the PPPoE client and the server, which could be
either a Cisco uBR7200 series router or a Home Gateway.
Router-Port Group Management Protocol
The Router-Port Group Management Protocol (RGMP) feature introduces a Cisco protocol that restricts
IP multicast traffic in switched networks. RGMP is a Layer 2 protocol that enables a router to
communicate to a switch (or a networking device that is functioning as a Layer 2 switch) the multicast
group for which the router would like to receive or forward traffic.
No New Hardware Features in Release 12.1(3)T
There are no new hardware features supported by the Cisco uBR7200 Series Universal Broadband
Routers in Cisco IOS Release 12.1(3)T.