Specifications

58
Release Notes for Cisco 7000 Family for Cisco IOS Release 12.1 T
78-10811-05
New and Changed Information
NTP MIB
Platforms: Cisco 7100 series and Cisco 7500 series routers
The Network Time Protocol (NTP) is used to synchronize timekeeping among a set of distributed time
servers and clients. The Cisco NTP MIB enables users to remotely monitor an NTP server using the
Simple Network Management Protocol (SNMP), provided the MIB itself is implemented on that server.
Use of the NTP MIB to monitor the NTP status of routing devices is accomplished using software on a
Network Management System (NMS). There are no new or modified Cisco IOS software commands
associated with this feature.
The Cisco implementation of the NTP MIB is based on NTP version 3 (RFC-1305). The MIB objects
are all read-only. SNMP requests are processed by reading the corresponding variables from the NTP
subsystem and returning them in the response. The NTP MIB defines a set of NTP server system
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 (CISCO-NTP-MIB.my, available
through Cisco.com at http://www.cisco.com/public/mibs/v2/).
Parser Cache
Platforms: Cisco 7100 series, Cisco 7200 series, and Cisco 7500 series routers
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 lists (ACLs)
are required. The parser chain cache can rapidly recognize and translate configuration lines which 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 12.1(5)T or later. A new
command, [no] parser cache, allows the disabling or re-enabling of this feature.
PIM Dense Mode State Refresh
Platforms: Cisco 7200 series and Cisco 7500 series routers
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 Radius Port Identification
Platforms: Cisco 7200 series and Cisco 7500 series routers
The PPPoE RADIUS Port Identification feature extends the concepts of NAS port and NAS port type
to include VLAN ID for PPPoE over 802.1Q VLANs. It also adds the NAS port format-d extension,
which was originally created for PPPoE over ATM and PPPoVLAN, to LACs and allows an LNS to
forward to a RADIUS server the NAS port format-d information sent to it by an LAC.
The PPPoE RADIUS Port Identification feature brings consistency to the command-line keywords and
value formats used to identify a NAS port and port type to a RADIUS server for the PPPoE over ATM,
PPPoE over 802.1Q VLAN, and PPPoE over L2TP tunnels.