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Glossary
NetBIOS
Network Basic Input/Output System: The
API employed by applications residing on an IBM
LAN to ask for services, such as session termination or
information transfer, from lower-level network pro-
cesses.
netflow switching
Collects detailed data for use
with circuit accounting and application-utilization
information. Because of all the additional data that
Netflow collects (and may export), expect an increase
in router overhead--possibly as much as a five-percent
increase in CPU utilization.
NetView
A mainframe network product from IBM,
used for monitoring SNA (Systems Network Architec-
ture) networks. It runs as a VTAM (Virtual Telecom-
munications Access Method) application.
NetWare
A widely used NOS created by Novell,
providing a number of distributed network services
and remote file access.
network address
Used with the logical network
addresses to identify the network segment in an inter-
network. Logical addresses are hierarchical in nature
and have at least two parts: network and host. An
example of a hierarchical address is 172.16.10.5,
where 172.16 is the network and 10.5 is the host
address.
network analyzer
Also known as protocol analyz-
ers. A device that collects and analyzes data on a con-
nected broadcast domain. The information provided
is a packet decode of data transiting the network. This
data is used to troubleshoot network problems.
Network layer
In the OSI reference model, it is
Layer 3--the layer in which routing is implemented,
enabling connections and path selection between two
end systems. See also: Application layer, Data-Link
layer, Physical layer, Presentation layer, Session layer,
and Transport layer.
Network Monitor
This software-based tool simply
monitors the network. It can do this in several ways,
including the Simple Network Management Protocol
(SNMP) and the Internet Control Message Protocol
(ICMP).
NFS
Network File System: One of the protocols in
Sun Microsystems' widely used file system protocol
suite, allowing remote file access across a network.
The name is loosely used to refer to the entire Sun pro-
tocol suite, which also includes RPC, XDR (External
Data Representation), and other protocols.
NHRP
Next Hop Resolution Protocol: In a non-
broadcast multi-access (NBMA) network, the proto-
col employed by routers in order to dynamically locate
MAC addresses of various hosts and routers. It
enables systems to communicate directly without
requiring an intermediate hop, thus facilitating
increased performance in ATM, Frame Relay, X.25,
and SMDS systems.
NHS
Next Hop Server: Defined by the NHRP pro-
tocol, this server maintains the next-hop resolution
cache tables, listing IP-to-ATM address maps of
related nodes and nodes that can be reached through
routers served by the NHS.
NIC
network interface card: An electronic circuit
board placed in a computer. The NIC provides net-
work communication to a LAN.
NLSP
NetWare Link Services Protocol: Novell's
link-state routing protocol, based on the IS-IS model.
NMP
Network Management Processor: A Catalyst
5000 switch processor module used to control and
monitor the switch.
NMS
Network Management Systems: A software/
hardware package that is used to monitor availability,
network performance, security, services, and policies.
node address
Used to identify a specific device in
an internetwork. Can be a hardware address, which is
burned into the network interface card or a logical net-
work address, which an administrator or server
assigns to the node.
nondesignated port
The Spanning-Tree Protocol
tells a port on a Layer-2 switch to stop transmitting
and creating a network loop. Only designated ports
can send frames.
non-stub area
In OSPF, a resource-consuming area
carrying a default route, intra-area routes, interarea
routes, static routes, and external routes. Non-stub
areas are the only areas that can have virtual links con-
figured across them and exclusively contain an anon-
ymous system boundary router (ASBR). Compare
with: stub area. See also: ASBR
and OSPF.
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