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Match CoS for Non-IPv4 Traffic
The match class of service (CoS) feature helps a service provider to classify packets based on CoS values while preserving its customers’
packet differentiated services code point (DSCP) values inside the service provider network. The match Cos for non-IPv4 feature provides
uniform class-level quality-of-service (QoS) semantics irrespective of traffic type on a dot1q-tunnel and regular trunk ports. This is
typically deployed in a Q-in-Q environment, where double-tagged IPv4 packets are forwarded as non-IPV4 packets.
L2PT over Trunk
Layer 2 Protocol Tunneling (L2PT) allows customer switches to participate in L2 protocols across a Service Provider network. This is
achieved by encapsulating Layer 2 protocol packets, such as Cisco Discovery Protocol (CDP), Spanning -Tree Protocol (STP), or VLAN
Trunking Protocol (VTP), before sending them across the service provider network. As a result the CPE switches on either side of the SP
network can continue to process the L2 protocol control packets as if they were being received from a directly connected neighboring
switch. The existing implementation allowed L2PT to be used only on tunnel ports. This feature will extend the functionality so that
L2PT will be available on trunk ports configured with dot1q encapsulation.
CoS Mutation
The CoS mutation feature enables Service Providers to provide differentiated services for video, voice, and data within the SP network. In
a typical L2 VPN offered by service providers, double tagged Q-in-Q traffic is forwarded with the outer tag representing service provider’s
VLAN and inner tag representing the customer’s VLAN. SPs could either retain the CoS values from the customer tag in the service
provider tag or change the CoS value of the outer service provider tag based on inner customer QoS matching and classification. As a
result, Differentiated levels of service can be provided within the service provider network.
IP Unnumbered for SVI
IP unnumbered interface configuration enables IP processing on an interface without assigning it an explicit IP address. IP Unnumbered
for SVI extends the current support for point-to-point links to switched virtual interfaces (SVIs). This feature is crucial in large service
provider environments where SVIs are used to terminate L2 traffic from the CPE. This feature helps to conserve IP addresses space and,
simplify configuration and address management.
CISCO IOS SOFTWARE PACKAGING FOR THE CISCO CATALYST 4500 SERIES
A new Cisco IOS Software package for Cisco Catalyst 4500 Series switches was introduced in Cisco IOS Software Release 12.2(25)SG.
It is a new foundation for features and functionality and provides consistency across all Cisco Catalyst switches. The new Cisco IOS
Software release train is designated as 12.2SG.
Prior Cisco IOS Software images for the Cisco Catalyst 4500 Series, formally known as “Basic Layer 3” and “Enhanced Layer 3” images,
now map to “IP Base” and “Enterprise Services,” respectively. BGP is now included in the “Enterprise Services” image. Unless otherwise
specified, all currently shipping Cisco Catalyst 4500 software features based on Cisco IOS Software are supported in the IP Base image of
Release 12.2(31)SGA, with a few exceptions:
The IP Base image does not support any enhanced routing-related features (including NSF/SSO, BGP, EIGRP, OSPF, IS-IS, Internetwork
Packet Exchange [IPX] protocol, AppleTalk, VRF-lite, and PBR). The IP Base image supports EIGRP-Stub for limited routing on Cisco
Catalyst 4500 Series Supervisor Engines II-Plus, II-Plus-TS, II-Plus-10GE, IV, V, and V-10GE. For more information on EIGRP-Stub
functionality, go to
http://www.cisco.com/en/US/technologies/tk648/tk365/technologies_white_paper0900aecd8023df6f.shtml
.