Setting A Time Range - Edge-Core ECS4110-28T Management Manual

precisely determined. It depends on the amount of hardware resources
reserved at runtime for this purpose.
Auto ACE Compression is a software feature used to compress all the
ACEs of an ACL to utilize hardware resources more efficiency. Without
compression, one ACE would occupy a fixed number of entries in TCAM.
So if one ACL includes 25 ACEs, the ACL would need (25 * n) entries in
TCAM, where "n" is the fixed number of TCAM entries needed for one
ACE. When compression is employed, before writing the ACE into
TCAM, the software compresses the ACEs to reduce the number of
required TCAM entries. For example, one ACL may include 128 ACEs
which classify a continuous IP address range like 192.168.1.0~255. If
compression is disabled, the ACL would occupy (128*n) entries of
TCAM, using up nearly all of the hardware resources. When using
compression, the 128 ACEs are compressed into one ACE classifying
the IP address as 192.168.1.0/24, which requires only "n" entries in
TCAM. The above example is an ideal case for compression. The worst
case would be if no any ACE can be compressed, in which case the used
number of TCAM entries would be the same as without compression. It
would also require more time to process the ACEs.
The order in which active ACLs are checked is as follows:
User-defined rules in IP and MAC ACLs for ingress or egress ports are
1.
checked in parallel.
Rules within an ACL are checked in the configured order, from top to
2.
bottom.
If the result of checking an IP ACL is to permit a packet, but the result
3.
of a MAC ACL on the same packet is to deny it, the packet will be
denied (because the decision to deny a packet has a higher priority for
security reasons). A packet will also be denied if the IP ACL denies it
and the MAC ACL accepts it.
Use the Security > ACL (Configure Time Range) page to sets a time range
S
ETTING A
during which ACL functions are applied.
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CLI R
EFERENCES
"Time Range" on page 782
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OMMAND
If both an absolute rule and one or more periodic rules are configured for
the same time range (i.e., named entry), that entry will only take effect if
the current time is within the absolute time range and one of the periodic
time ranges.
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HAPTER
Access Control Lists