Ericsson ECN330, User Manual

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Glossary
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Modal Bandwidth
Bandwidth for multimode fiber is referred to as
modal bandwidth because it varies with the
modal field (or core diameter) of the fiber.
Modal bandwidth is specified in units of MHz
per km, which indicates the amount of
bandwidth supported by the fiber for a one km
distance.
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 Diameter
Wire distance between two end stations in the
same collision domain.
Network Time Protocol (NTP)
NTP provides the mechanisms to synchronize
time across the network. The time servers
operate in a hierarchical-master-slave
configuration in order to synchronize local
clocks within the subnet and to national time
standards through wire or radio.
Open Shortest Path First (OSPF)
OSPF is a link-state routing protocol that
functions better over a larger network such as
the Internet, as opposed to distance-vector
routing protocols such as RIP. It includes
features such as unlimited hop count,
authentication of routing updates, and Variable
Length Subnet Masks (VLSM).
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-speed 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.
Protocol-Independent Multicasting
(PIM)
This multicast routing protocol floods multicast
traffic downstream, and calculates the
shortest-path back to the multicast source
network through reverse path forwarding. PIM
uses the router’s IP routing table rather than
maintaining a separate multicast routing table