Accton Technology ES4710BD - Manual (Page 267)

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E ES4710BD 10 Slots L2/L3/L4 Chassis Switch
Chapter 12 ACL Configuration
12.1 Introduction to ACL
ACL (Access Control List) is an IP packet filtering mechanism employed in switches, providing
network traffic control by granting or denying access through the switches, effectively safeguarding
the security of networks. The user can lay down a set of rules according to some information
specific to packets, each rule describes the action for a packet with certain information matched:
“permit” or “deny”. The user can apply such rules to the incoming or outgoing direction of switch
ports, so that data streams in the specific direction of specified ports must comply with the ACL
rules assigned.
12.1.1 Access list
Access list is a sequential collection of conditions that corresponds to a specific rule. Each rule
consists of filter information and the action when the rule is matched. Information included in a rule
is the effective combination of conditions such as source IP, destination IP, IP protocol number and
TCP port. Access lists can be categorized by the following criteria:
z Filter information based criterion: IP access list (layer 3 or higher information), MAC
access list (layer 2 information), and MAC-IP access list (layer 2 or higher). The current
implementation supports IP access list only, the other two functions will be provided later.
z Configuration complexity based criterion: standard and extended, the extended mode
allows more specific filtering of information.
z Nomenclature based criterion: numbered and named.
Description of an ACL should cover the above three aspects.
12.1.2 Access-group
When a set of access lists are created, they can be applied to traffic of any direction on all ports.
Access-group is the description to a the binding of an access list to the specified direction on a
specific port. When an access-group is created, all packets from in the specified direction through
the port will be compared to the access list rule to decide whether to permit or deny access.
12.1.3 Access list Action and Global Default Action
There are two access list actions and default actions: “permit” or “deny”