Microsoft ES4649 Switch User Manual


 
Glossary-5
Glossary
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 via 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.
Quality of Service (QoS)
QoS refers to the capability of a network to provide better service to selected traffic
flows using features such as data prioritization, queuing, congestion avoidance and
traffic shaping. These features effectively provide preferential treatment to specific
flows either by raising the priority of one flow or limiting the priority of another flow.
Protocol-Independent Multicasting (PIM)
This multicast routing protocol floods multicast traffic downstream, and calculates
the shortest-path back to the multicast source network via reverse path forwarding.
PIM uses the router’s IP routing table rather than maintaining a separate multicast
routing table as with DVMRP. PIM - Sparse Mode is designed for networks where
the probability of a multicast client is low, such as on a Wide Area Network. PIM -