Information Technology Reference
In-Depth Information
the two implementations support. When you use ACLs for prefix filtering, only the source
and destination addresses are relevant. It is also important to note that wildcard bits are not
supported.
Table 12-3
IPv6 ACL Field Matching
Before Releases
12.2(13)T and 12.0(23)S
Releases 12.2(13)T or
12.0(23)S and Later
Field
Protocol
X
Source Address
X
X
Destination Address
X
X
Source Port
X
Destination Port
X
Flow-label
X
Fragment Header
X
Timeout
X
Routing Header
X
Sequence
X
DSCP
X
The prefix list functionality has been extended to support IPv6 route filtering. Prefix lists
with IPv6 are used only for prefix filtering, not for packet filtering, just like IPv4 prefix
lists. Example 12-2 shows an IPv6 prefix list.
Example 12-2
IPv6 Prefix List Example
ipv6 prefix-list FILTER_IN seq 5 permit 2001:400::/29
ipv6 prefix-list FILTER_IN seq 10 permit 2001:600::/29
ipv6 prefix-list FILTER_IN seq 15 permit 2001:800::/29
ipv6 prefix-list FILTER_IN seq 20 permit 3FFE::/16
ipv6 prefix-list FILTER_IN seq 25 permit 2002::/16
ipv6 prefix-list FILTER_IN seq 30 permit ::/80
ipv6 prefix-list FILTER_IN seq 35 deny ::/0
Cisco IOS software automatically abbreviates IPv6 addresses if possible.
NOTE
The preferred method of prefix filtering is the use of prefix lists. ACLs are used primarily
for packet filtering.
