7-1
Chapter 7: Access Control Lists
Access Control Lists (ACL) provide packet filtering for IPv4 frames (based on
address, protocol, Layer 4 protocol port number or TCP control code), IPv6 frames
(based on address, next header type, or flow label), 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 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:
• Each ACL can have up to 32 rules.
• The maximum number of ACLs is also 32.
• The maximum number of rules that can be bound to the ports is 96 for each of the
following list types: MAC ACLs, IP ACLs (including Standard and Extended ACLs),
IPv6 Standard ACLs, and IPv6 Extended ACLs. For the SMC8926EM, all ports
share this quota. For the SMC8950EM, ports 1-24 share a quota of 96 rules, and
ports 25-50 share another quota of 96 rules (since there are two switch chips in this
system).
The order in which active ACLs are checked is as follows:
1. User-defined rules in IP and MAC ACLs for ingress ports are checked in parallel.
2. Rules within an ACL are checked in the configured order, from top to bottom.
3. If the result of checking an IP ACL is to permit a packet, but the result 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.
Setting the ACL Name and Type
Use the ACL Configuration page to designate the name and type of an ACL.
Command Attributes
•
Name
– Name of the ACL. (Maximum length: 16 characters)
•
Type
– There are three filtering modes:
-
IP Standard
: IPv4 ACL mode that filters packets based on the source IPv4
address.
Summary of Contents for 8926EM
Page 6: ...ii ...
Page 34: ...Getting Started ...
Page 44: ...Introduction 1 10 1 ...
Page 62: ...Initial Configuration 2 18 2 ...
Page 64: ...Switch Management ...
Page 76: ...Configuring the Switch 3 12 3 ...
Page 118: ...Basic Management Tasks 4 42 4 ...
Page 164: ...User Authentication 6 28 6 ...
Page 176: ...Access Control Lists 7 12 7 ...
Page 284: ...Quality of Service 14 8 14 ...
Page 294: ...Multicast Filtering 15 10 15 ...
Page 300: ...Domain Name Service 16 6 16 ...
Page 310: ...Dynamic Host Configuration Protocol 17 10 17 ...
Page 320: ...Configuring Router Redundancy 18 10 18 ...
Page 344: ...IP Routing 19 24 19 ...
Page 356: ...Unicast Routing 20 12 20 Web Click Routing Protocol RIP Statistics Figure 20 5 RIP Statistics ...
Page 386: ...Unicast Routing 20 42 20 ...
Page 388: ...Command Line Interface ...
Page 400: ...Overview of the Command Line Interface 21 12 21 ...
Page 466: ...SNMP Commands 24 16 24 ...
Page 520: ...Access Control List Commands 26 18 26 ...
Page 546: ...Rate Limit Commands 30 2 30 ...
Page 612: ...VLAN Commands 34 24 34 ...
Page 626: ...Class of Service Commands 35 14 35 ...
Page 670: ...DHCP Commands 39 16 39 ...
Page 716: ...IP Interface Commands 41 36 41 ...
Page 768: ...IP Routing Commands 42 52 42 ...
Page 770: ...Appendices ...
Page 791: ......