LevelOne GEL-5261, User Manual

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Chapter 12
| Security Measures
Access Control Lists
Figu re 175: Showing the SSH User’s Public Key
Access Control Lists
Access Control Lists (ACL) provide packet filtering for IPv4/IPv6 frames (based on
address, protocol, Layer 4 protocol port number or TCP control code), IPv6 frames
(based on address, DSCP traffic class, or next header type), or any frames (based on
MAC address or Ethernet type). To filter incoming packets, first create an access list,
add the required rules, and then bind the list to a specific port.
Configuring Access Control Lists –
An ACL is a sequential list of permit or deny conditions that apply to IP addresses,
MAC addresses, or other more specific criteria. This switch tests ingress or egress
packets against the conditions in an ACL one by one. A packet will be accepted as
soon as it matches a permit rule, or dropped as soon as it matches a deny rule. If no
rules match, the packet is accepted.
Command Usage
The following restrictions apply to ACLs:
◆ The maximum number of ACLs is 512.
◆ The maximum number of rules per system is 2048 rules.
◆ An ACL can have up to 2048 rules. However, due to resource restrictions, the
average number of rules bound to the ports should not exceed 20.
◆ The maximum number of rules that can be bound to the ports is 64 for each of
the following list types: MAC ACLs, IP ACLs (including Standard and Extended
ACLs), IPv6 Standard ACLs, and IPv6 Extended ACLs.
The maximum number of rules (Access Control Entries, or ACEs) stated above is
the worst case scenario. In practice, the switch compresses the ACEs in TCAM (a
hardware table used to store ACEs), but the actual maximum number of ACEs