microwaves
Very short radio waves used to transmit data over 890MHz.
modem A device used to modulate and demodulate the signals that pass through it. It converts the direct
current pulses of the serial digital code from the controller into the analog signal that is compatible
with the telephone network.
multicast
A single packet transmission from one sender to a specific group of destination nodes.
multilayer switches
A combination of Layer 2, 3, and 4 switches that use the concept of route once, switch many.
multiprocessor
Support for multiple processors in a single machine.
Multiprotocol Over ATM (MPOA)
An ATM forum standard that includes enhancements to LANE and adds Layer 3 switching
capabilities to ATM switches.
Multistation Access Unit (MAU or MSAU)
A concentrator or hub used in a Token Ring network. It organizes the connected nodes into an internal
ring and uses the RI (ring in) and RO (ring out) connectors to expand to other MAUs on the network.
NetFlow Switching
A feature incorporated into the Multilayer Switching Module (MSM), NetFlow Feature Card (NFFC),
and NFFC II that was originally instituted and developed for Cisco’s enterprise routers. NetFlow
allows for transparent switching in hardware while incorporating QoS features including security,
multicast forwarding, multilayer switching, NetFlow data exporting, and packet filtering at Layer 3
and Layer 4 application ports.
NetWare Core Protocol (NCP)
NetWare protocol that provides a method for hosts to make calls to a NetWare server for services and
network resources.
network down
Situation in which the clients are unable to utilize the services of the network. This can be
administrative, scheduled downtime for upgrades or maintenance, or it can be the result of a serious
error.
Network Driver Interface Specification (NDIS)
Microsoft proprietary specification or standard for a protocol−independent device driver. These
drivers allow multiple protocols to be bound to the same NIC, allowing the card to be used by
multiple operating systems. NDIS is similar to Open Data−Link Interface (ODI).
network ID
The part of the TCP/IP address that specifies the network portion of the IP address. It is determined
by the class of the address, which is determined by the subnet mask used.
Network Interface Card (NIC)
The hardware component that serves as the interface, or connecting component, between your
network and the node. It has a transceiver, a MAC address, and a physical connector for the network
cable. Also known as a network adapter.
Network Interface layer
The bottom layer of the TCP/IP architectural model, which maps to the bottom two layers of the OSI
Reference Model. It’s responsible for sending, receiving, and interacting with bits at the Physical
layer.
Network layer
The third layer of the OSI Reference Model, where routing based on node addresses (IP or IPX
addresses) occurs.
Network Management Processor (NMP)
A feature of the Catalyst Supervisor Engine that is responsible for general control and some
management functions of the switch. It is responsible for executing the system’s configuration
changes, the Command Line Interface (CLI), and running diagnostics on boot components as well as
new components.
Network Time Protocol (NTP)
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