Specifications

Table Of Contents

Release Notes for Cisco 7000 Family for Cisco IOS Release 12.1 T

78-10811-05

New and Changed Information

In deployment cases where IGMP v3 cannot be used (for example, if it is not supported by the receiver

host or its applications), there are two other mechanisms to enable Source Specific Multicast (SSM):

URL Rendezvous Directory (URD) and IGMP v3 lite. Both of these features were introduced with SSM

in Cisco IOS Release 12.1(5)T.

Inter-Autonomous Systems MPLS VPN Support

Platforms: Cisco 7200 series and Cisco 7500 series routers

The inter-autonomous systems for MPLS VPNs feature provides a seamless integration of autonomous

systems and service providers. Separate autonomous systems from different service providers can

communicate by exchanging IP v4 network layer reachability information (NLRI) in the form of

VPN-IP v4 addresses. The autonomous systems’ border edge routers use exterior border gateway

protocol (EBGP) to exchange that information. Then, an interior gateway protocol (IGP) distributes the

network layer information for VPN-IP v4 prefixes throughout each VPN and each autonomous system.

Interface Index Persistence

Platforms: Cisco 7200 series and Cisco 7500 series routers

One of the most commonly used identifiers used in SNMP-based network management applications is

the Interface Index (ifIndex) value. IfIndex is a unique identifying number associated with a physical

or logical interface; as far as most software is concerned, the ifIndex is the name of the interface.

Although there is no requirement in the relevant RFCs that the correspondence between particular

ifIndex values and their interfaces be maintained across reboots, applications such as device inventory,

billing, and fault detection increasingly depend on the maintenance of this correspondence.

Cisco IOS Release 12.1(5)T adds support for an ifIndex value that can persist across reboots, so that

users can avoid the workarounds previously required for consistent interface identification. The

Interface Index Persistence feature allows for greater accuracy when collecting and processing network

management data by uniquely identifying input and output interfaces for traffic flows and SNMP

statistics. Relating each interface to a known entity (such as an ISP customer) allows network

management data to be more effectively utilized.

Interface Range Specification

Platforms: Cisco 7200 series and Cisco 7500 series routers

The Interface Range Specification feature allows specification of a range of interfaces to which

subsequent commands are applied and supports definition of macros that contain an interface range. The

Interface Range Specification feature is implemented with the range keyword, which is used with the

interface command. In the interface conﬁguration mode with the range keyword, all entered commands

are applied to all interfaces within the range until you exit interface conﬁguration mode.

Interworking Signalling Enhancements for H.323 and SIP VoIP

Platforms: Cisco 7200 series and Cisco 7500 series routers

The Interworking Signaling Enhancements for H.323 and SIP VoIP feature enables VoIP networks to

properly signal the setup and tear-down of calls when interworking with PSTN networks. These

enhancements ensure that in-band tones and announcements are generated when needed so that the

voice path is cut-through at the appropriate point of call setup and that early alerting (ringing) does not

occur. In addition, support for network-side ISDN and the reducing of speech clipping is addressed.