General Security Measures

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General Security Measures

This switch supports many methods of segregating traffic for clients attached to
each of the data ports, and for ensuring that only authorized clients gain access to
the network. Private VLANs and port-based authentication using IEEE 802.1X are
commonly used for these purposes. In addition to these methods, several other
options of providing client security are supported by this switch. These include
port-based authentication, which can be configured for network client access
by specifying a fixed set of MAC addresses. The addresses assigned to DHCP
clients can also be carefully controlled using static or dynamic bindings with the IP
Source Guard and DHCP Snooping commands.
This switch provides client security using the following options:
Private VLANs – Provide port-based security and isolation between ports within the
assigned VLAN. (See "Configuring Private VLANs" on page 3-184.)
Port Security – Configure secure addresses for individual ports.
802.1X – Use IEEE 802.1X port authentication to control access to specific ports.
(See "Configuring 802.1X Port Authentication" on page 3-80.)
Network Access - Configures MAC authentication and dynamic VLAN assignment.
ACL - Access Control Lists 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).
DHCP Snooping – Filters IP traffic on insecure ports for which the source address
cannot be identified via DHCP snooping. (See "Filtering IP Addresses for
Management Access" on page 3-99.)
IP Source Guard – Filters untrusted DHCP messages on insecure ports by building
and maintaining a DHCP snooping binding table. (See "IP Source Guard" on
page 3-107.)
Note: The priority of execution for the filtering commands is Port Security, Port
Authentication, Network Access, Access Control Lists, IP Source Guard, and then
DHCP Snooping.