Specifications

59
Release Notes for Cisco 7000 Family for Cisco IOS Release 12.1 T
78-10811-05
New and Changed Information
PPP Over Fast Ethernet 802.1Q
Platforms: Cisco 7200 series and Cisco 7500 series routers
The PPPoE over IEEE 802.1Q Encapsulation feature adds support for running PPP over Ethernet over
IEEE 802.1Q encapsulation. IEEE 802.1Q encapsulation enables you to interconnect a VLAN capable
router with another VLAN capable device.
Quality of Service for Virtual Private Networks
Platforms: Cisco 7100 series and Cisco 7200 series routers
With the introduction of the Quality of Service for Virtual Private Networks (QoS for VPNs) feature,
packets can now be classified before tunneling and encryption occur (a process known as
preclassification). The preclassification process is important because all tunnel traffic that is not
preclassified is treated identically, making traffic flows impossible to adjust in congested environments.
When the QoS for VPN feature is enabled, the QoS features on the output interface classify packets
before encryption, allowing traffic flows to be adjusted in congested environments. The end result is
more effective packet tunneling.
For additional information on the QoS for VPNs feature, see the Quality of Service for Virtual Private
Networks feature module on Cisco.com and the Documentation CD-ROM.
Router-Port Group Management Protocol
Platforms: Cisco 7100 series, Cisco 7200 series, and Cisco 7500 series routers
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. RGMP restricts multicast traffic at
the ports of RGMP-enabled switches that lead to interfaces of RGMP-enabled routers. RGMP is
designed for switched Ethernet backbone networks running Protocol Independent Multicast (PIM)
sparse mode.
RSVP Support for Frame Relay
Platforms: Cisco 7200 series and Cisco 7500 series routers
Queueing manages congestion on a router interface or a virtual circuit (VC). In a Frame Relay
environment, the congestion point may not be the interface itself, but it may be the VC because of the
committed information rate (CIR). For real-time traffic (voice flows) to be transmitted in a timely
manner, the data rate must not exceed the CIR or packets might be dropped causing voice quality issues.
Frame Relay traffic shaping (FRTS) is configured on the interfaces to control the outbound traffic rate
by preventing the router from exceeding the CIR. This means that fancy queueing such as class-based
weighted fair queueing (CBWFQ), low latency queueing (LLQ), and weighted fair queueing (WFQ),
can run on the VC to provide the quality of service (QoS) guarantees for the traffic.
Previously, RSVP reservations were not constrained by the CIR of the flow’s outbound VC. As a result,
oversubscription could occur when the sum of the RSVP traffic and other traffic exceeded the CIR.