User guide

Release Notes for Cisco 2500 Series for Cisco IOS Release 12.0 T

78-5563-07 Rev.H0

New and Changed Information

• Masquerade or protection against attempting management operations not authorized for some

principal by assuming the identity of another principal that has the appropriate authorizations

• Message Stream Modification or protection against messages getting maliciously re-ordered,

delayed or replayed in order to effect unauthorized management operations

• Disclosure or protection against eavesdropping on the exchanges between SNMP engines. Three

different types of communication mechanisms are available for this protection strategy. They are:

–

communication without authentication and privacy (NoAuthNoPriv)

–

communication with authentication and without privacy (AuthNoPriv)

–

communication with authentication and privacy (AuthPriv)

Token Ring MPOA

Token Ring Multiprotocol over ATM (MPOA) allows Token Ring hosts in an ATM network to

communicate over alternate paths (called shortcuts) through the ATM network, which bypasses

intermediate router hops that would otherwise be encountered in the default path.

Token Ring MPOA is an extension to LAN Emulation (LANE). Using the Next Hop Resolution

Protocol (NHRP), and MPOA server (MPS) on the router, and MPO clients (MPCs) on the ATM edge

devices, a direct virtual channel connection (VCC) between the ingress and egress edge devices is

established. Token Ring MPOA allows Token Ring LANE clients to forward unicast IP packets between

subnets to other Token Ring LANE clients through this shortcut VCC path on the ATM network.

Web Cache Communications Protocol Version 2 (WCCPv2)

The Web Cache Communications Protocol enables Cisco IOS routing platforms to transparently

redirect content requests (for example, web requests) from clients to a locally connected Cisco Cache

Engine (or Cache Cluster) instead of the intended origin server. When a Cache Engine receives such a

request, it attempts to service it from its own local cache if the requested information is present. If not,

the Cache Engine issues its own request to the originally requested origin server to get the required

information. When the Cache Engine retrieves the requested information, it forwards it to the requesting

client and caches it to fulfill future requests, thus maximizing download performance and significantly

reducing WAN transmission costs.