H3C S5500-SI Series, Operation Manual

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ACL Overview
In order to filter traffic, network devices use sets of rules, called access control lists (ACLs), to identify
and handle packets.
When configuring ACLs, go to these chapters for information you are interested in:
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ACL Overview
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IPv4 ACL Configuration
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IPv6 ACL Configuration
Unless otherwise stated, ACLs refer to both IPv4 ACLs and IPv6 ACLs throughout this document.
Introduction to ACL
Introduction
As network scale and network traffic are increasingly growing, network security and bandwidth
allocation become more and more critical to network management. Packet filtering can be used to
efficiently prevent illegal users from accessing networks and to control network traffic and save network
resources. Access control lists (ACL) are often used to filter packets with configured matching rules.
ACLs are sets of rules (or sets of permit or deny statements) that decide what packets can pass and
what should be rejected based on matching criteria such as source MAC address, destination MAC
address, source IP address, destination IP address, and port number.
Application of ACLs on the Switch
The switch supports two ACL application modes:
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Hardware-based application: An ACL is assigned to a piece of hardware. For example, an ACL is
applied to an Ethernet interface or VLAN interface for packet filtering or is referenced by a QoS
policy for traffic classification. Note that when an ACL is referenced to implement QoS, the actions
defined in the ACL rules, deny or permit, do not take effect; actions to be taken on packets
matching the ACL depend on the traffic behavior definition in QoS. For details about traffic behavior,
refer to the QoS part in QoS Volume .
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Software-based application: An ACL is referenced by a piece of upper layer software. For example,
an ACL can be referenced to configure login user control behavior, thus controlling Telnet, SNMP
and Web users. Note that when an ACL is reference by the upper layer software, actions to be
taken on packets matching the ACL depend on those defined by the ACL rules. For details about
login user control, refer to the part about login configuration in System Volume .