User manual

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GLOSSARY
ACL Access Control List. ACLs can limit network traffic and restrict access to
certain users or devices by checking each packet for certain IP or MAC (i.e.,
Layer 2) information.
ARP Address Resolution Protocol converts between IP addresses and MAC
(hardware) addresses. ARP is used to locate the MAC address
corresponding to a given IP address. This allows the switch to use IP
addresses for routing decisions and the corresponding MAC addresses to
forward packets from one hop to the next.
COS Class of Service is supported by prioritizing packets based on the required
level of service, and then placing them in the appropriate output queue.
Data is transmitted from the queues using weighted round-robin service to
enforce priority service and prevent blockage of lower-level queues.
Priority may be set according to the port default, the packet’s priority bit
(in the VLAN tag), TCP/UDP port number, IP Precedence bit, or DSCP
priority bit.
DHCP Dynamic Host Control Protocol. Provides a framework for passing
configuration information to hosts on a TCP/IP network. DHCP is based on
the Bootstrap Protocol (BOOTP), adding the capability of automatic
allocation of reusable network addresses and additional configuration
options.
DHCP OPTION 82 A relay option for sending information about the requesting client (or an
intermediate relay agent) in the DHCP request packets forwarded by the
switch and in reply packets sent back from the DHCP server. This
information can be used by DHCP servers to assign fixed IP addresses, or
set other services or policies for clients.
DHCP SNOOPING A technique used to enhance network security by snooping on DHCP server
messages to track the physical location of hosts, ensure that hosts only use
the IP addresses assigned to them, and ensure that only authorized DHCP
servers are accessible.