Quick Reference Guide

Reference Guide for the Model RT338 ISDN Router
Glossary
3
masquerading
A technique by which several hosts share a single IP address for access to the
Internet. This process is an extension of Network Address Translator (NAT).
See also Network Address Translator.
Maximum Receive
Unit
MRU. The size in bytes of the largest packet that can be sent or received.
Most Significant Bit or
Most Significant Byte
The portion of a number, address, or field that is farthest left when written as a
single number in conventional hexadecimal ordinary notation. The part of the
number having the most value.
Multilink Protocol
MP. An extension to the Point-to-Point Protocol (PPP) allowing the
combination of both B channels to provide a single 128 Kbps channel.
See Point-to-Point Protocol.
Multiple Subscriber
Numbering
MSN. A service of the telephone company in which a range of numbers is
assigned to one line. Each device attached to that line (for example, a phone or
router) must know which number it should answer.
National ISDN (NI-1)
Bellcore standard for first phase of ISDN interoperability among U.S.
telephone companies.
NAT
See Network Address Translator.
netmask
A number that explains which part of an IP address comprises the network
address and which part is the host address on that network. It can be
expressed in dotted-decimal notation or as a number appended to the
IP address. For example, a 28-bit mask starting from the MSB can be shown
as 255.255.255.192 or as /28 appended to the IP address.
Network Address
Translator
(or Translation)
NAT. A proposal for IP address reuse, where the local IP address is mapped to
a globally unique address. See also masquerading.
NT1 (Network
Termination 1)
Termination device that connects the user’s equipment to the ISDN network.
Converts the local equipment’s four-wire S/T interface to the two-wire
telephone company interface. The NT1 is provided by the telephone company
in most of the world, but it is provided by the user in North America.
Referred to in some areas as a DSU.
numbered links
A method of connecting two LANs by way of a WAN, where the two WAN
end points have their own IP addresses.
PAP
See Password Authentication Protocol.
POTS
See Plain Old Telephone Service.
Glossary.fm Page 3 Friday, October 6, 2000 5:36 PM