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Configuration:
Basic Advanced TCP/IP Wireless
VT2400/VT2500 Series Voice Gateway User Guide
134
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MAC address
The Media Access Control address is a unique, 48-bit value permanently saved in ROM at the factory to
identify each Ethernet network device. It is expressed as a sequence of 12 hexadecimal digits printed
on a the bottom of the VT2400 or VT2500. You need to provide the HFC MAC address to the cable
provider. Also called an Ethernet address, physical address, hardware address, or NIC address.
MB
One megabyte; equals 1,024 x 1,024 bytes, 1,024 kilobytes, or about 8 million bits.
Mbps
Million bits per second (megabits per second). A rate of data transfer.
media
The various physical environments through which signals pass; for example, coaxial, unshielded
twisted-pair (UTP), or fiber-optic cable.
MIB
A management information base is a unique hierarchical structure of software objects used by the
SNMP manager and agent to configure, monitor, or test a device.
MHz
Megahertz — one million cycles per second. A measure of radio frequency.
MPDU
MAC protocol data unit (PDU)
MSDU
MAC service data unit
MSO
Multiple Systems Operator. A company that owns and operates more than one cable system. Also
called a group operator.
MTA
Multimedia Terminal Adapter. See
S-MTA
.
MTU
The Maximum Transmission Unit is the largest amount of data that can be transmitted in one discrete
message on a given physical network. The MTU places an upper bound on the size of a message that
can be transferred by the network in a single frame. Messages exceeding the MTU must be fragmented
before transmission, and reassembled at the destination.
multicast
A data transmission sent from one sender to multiple receivers. See also
broadcast
and
unicast
.
mW
milliwatts
NAS
network access server
NAT
Network Address Translation is an Internet standard for a LAN to use one set of IP addresses for
internal traffic and a second set of IP addresses for external traffic. NAT provides some security
because the IP addresses of VT2500 LAN computers are invisible on the Internet.
If NAT is enabled on the Gateway page, there is a one-to-one mapping between each public IP
address and client IP address.
NAPT
Network Address Port Translation is the most common form of address translation between public and
private IP addresses. NAPT is a mapping of one public IP address to many private IP addresses. If
NAPT is enabled on the Gateway page, one public IP address is mapped to an individual private
IP address for up to 245 LAN clients.
NEC
National Electrical Code (in the United States) are the regulations for construction and installation of
electrical wiring and apparatus, suitable for mandatory application by a wide range of state and local
authorities.
network
Two or more computers connected to communicate with each other. Networks have traditionally been
connected using some kind of wiring.
network driver
Software packaged with a NIC that enables the computer to communicate with the NIC.