QTech QSW-2800 series, Руководство по настройке

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Chapter 37 ACL Configuration
37.1 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 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 direction of switch
ports, so that data streams of specified ports must comply with the ACL rules assigned.
37.1.1 Access-list
Access-list is a sequential collection of conditions that corresponds to a specific rule. Each rule
consist 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, UDP port. Access-lists can be categorized by the following criteria:
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 layer 3 or higher).
Configuration complexity based criterion: standard and extended, the extended mode allows
more specific filtering of information.
Nomenclature based criterion: numbered and named.
Description of an ACL should cover the above three aspects.
37.1.2 Access-group
When a set of access-lists are created, they can be applied to traffic of incoming direction on
all ports. Access-group is the description to the binding of an access-list to the incoming
direction on a specific port. When an access-group is created, all packets from in the incoming
direction through the port will be compared to the access-list rule to decide whether to permit
or deny access.
The current firmware only supports ingress ACL configuration.
37.1.3 Access-list Action and Global Default Action
There are two access-
list actions and default actions: “permit” or “deny”. The following rules
apply: