Glossary
Glossary-4
Multicast Switching
A process whereby the switch filters incoming multicast frames for services for
which no attached host has registered, or forwards them to all ports contained within
the designated multicast VLAN group.
Network Time Protocol (NTP)
NTP provides the mechanisms to synchronize time across the networ k. The time
servers operate in a hierarchical-master-slave configuration in orde r to synchronize
local clocks within the subnet and to national time standards via wire or radio.
Out-of-Band Management
Management of the network from a station not attached to the network.
Port Authentication
See IEEE 802.1x.
Port Mirroring
A method whereby data on a target port is mirrored to a monitor port for
troubleshooting with a logic analyzer or RMON probe . This allows data on the target
port to be studied unobstructively.
Port Trunk
Defines a network link aggregation and trunking method which specifies how to
create a single high-speed logical link that combines several lower-sp eed physical
links.
Private VLANs
Private VLANs provide port-based security and isolation between ports within the
assigned VLAN. Data traffic on downlink ports can only be forwarded to, and from,
uplink ports.
Remote Authentication Dial-in User Service (RADIUS)
RADIUS is a logon authentication protocol that uses software running on a central
server to control access to RADIUS-c ompliant devices on the network.
Remote Monitoring (RMON)
RMON provides comprehensive network monitoring capabilities. It eli minates the
polling required in standard SNMP, and can set alarms on a variety of traffic
conditions, including specific error types.
Rapid Spanning Tree Protocol (RSTP)
RSTP reduces the convergence time for network topology changes to a bout 10% of
that required by the older IEEE 802.1D STP standard.