Cisco 7609-S Software Configuration Guide - Page 498

Configuring IPv6 Address Compression Chapter 34 Understanding Cisco IOS ACL Support Table 34-1 Compressible Address Types and Methods Address Type EUI-64 based on MAC address Embedded IPv4 address Link Local Others Compression Method This address is compressed by removing 16 bits from bit locations [39:24]. No information is lost when the hardware compresses these addresses. This address is compressed by removing the upper 16 bits. No information is lost when the hardware compresses these addresses. These addresses are compressed by removing the zeros in bits [95:80] and are identified using the same packet type as the embedded IPv4 address. No information is lost when the hardware compresses these addresses. If the IPv6 address does not fall into any of the above categories, it is classified as other. If the IPv6 address is classified as other, the following occurs: • If the compress mode is on, the IPv6 address is compressed similarly to the EUI-64 compression method (removal of bits [39:24]) to allow for the Layer 4 port information to be used as part of the key used to look up the QoS TCAM, but Layer 3 information is lost. • If the global compression mode is off, the entire 128 bits of the IPv6 address are used. The Layer 4 port information cannot be included in the key to look up the QoS TCAM because of the size constraints on the IPv6 lookup key. To turn on the compression of IPv6 addresses, enter the mls ipv6 acl compress address unicast command. To turn off the compression of IPv6 addresses, enter the no form of this command. This example shows how to turn on address compression for IPv6 addresses: Router(config)# mls ipv6 acl compress address unicast Router(config)# This example shows how to turn off address compression for IPv6 addresses: Router(config)# no mls ipv6 acl compress address unicast Router(config)# 34-4 Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX OL-4266-08