Multi Tech Equipment MTA128ST manual PPPMultilink Protocol or MP-is an Internet

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Glossary

organization that prepares standards for resolving communications issues and problems.

L

LAPB (Link Access Procedure Balanced)—Based on the X.25 Layer 2 specification. A full-duplex, point- to-point, bit-synchronous protocol commonly used as a data link control protocol to interface X.25 DTEs.

LAPB is the link initialization procedure that estab- lishes and maintains communications between the DTE and the DCE.

LAPD (Link Access Protocol for the

D-Channel)—Based on the ISDN Q.921 specification. A full-duplex point-to-point bit-synchronous link-level protocol for ISDN connections; different from LAPB in its framing sequence. Transmission is in units calledframes, and a frame may contain one or more X.25

packets.

link optimization—An ISDN feature that permits only user data to open the communications link and keeps administrative packets from opening the link. A cost saving feature that ensures that remote connections are not unnecessarily utilized.

local loop—A transmission path, typically twisted- pair wire, between an individual subscriber and the nearest public telecommunications network switching center. Also called the subscriber loop.

LT (loop termination)—A device, similar to an NT1, that terminates the local loop at the carrier’s central switching office. The LT provides the interface to the ISDN U reference point. Contrast ET (exchange termination).

MP+(MultiLink Protocol Plus)—An extension to the PPP Multilink Protocol (MP) convered in IETF RFC 1717. MP+ is a new control protocol for managing multiple data links that are bundled by MP. Also called the Multichannel Protocol Plus or MPP.

MS-CHAP—Microsoft version of CHAP.

multilink—In point-to-point protocol, literally many links. A procedure used to route data packets over many links for increased bandwidth (e.g., two B-channels on a single BRI for 128 Kbps).

mux (multiplexer)—A device that merges several signals into one composite signal for transmission over a single medium or channel. A demultiplexer, built into most muxes, reverses the process at the receiving end.

N

nailed connection—A permanent or dedicated circuit of a previously switched circuit or circuits.

nailed-upcircuit—A semi-permanent circuit established through a circuit-switching facility for point-to-point connectivity.

NAK (negative acknowledgment)—A communications code used to indicate that a message was not properly received, or that a terminal does not wish to transmit. Contrast with ACK.

network—A group of computers connected by cables or other means and using software that enables them to share equipment, such as printers and disk drives to exchange information.

NI-1(National ISDN-1)—A physical standard to make all compliant ISDN lines appear the same. With ISDN-1 installed, additional costs are not incurred when changing from prestandard ISDN to standard ISDN. Most RBOCs now are moving to ISDN-1.

 

M

NI-2(National ISDN-2)—A physical standard subsequent to

 

MD5(MD5 Message-Digest Algorithm)—Takes a

NI1. When tested and deployed, NI-2 will provide additional

 

features and enhanced plug and play capabilities.

 

message if arbitrary length as input and produces it

 

as output as a 128-bit fingerprint or message digest

node—Any point within a network that has been

 

of the input. The MD5 algorithm is used for digital

assigned an address.

 

signature applications where a large file must be

NT (network termination)—Devices that form the boundary

 

compressed in a secure manner before being

between customer premise equipment and telephone

 

encrypted with a private (secret) key under

company equipment. Two types of NTs are used: NT1 and

 

public-key cryptisystem.

NT2.

 

MLPPP (Multilink Point-to-Point Protocol, also the

NT1 (Network TerminationType 1)—An interface device used

 

PPPMultilink Protocol or MP)—is an Internet

in the BRI portion of ISDN to connect four-wire (S/T) ISDN

 

standards track protocol for a methyod of splittingm

devices to the two-wire (2BIQ U) IDN. It provides basic rate

 

recombining, and sequencing datagrams across

access in a 2B+D format with two 64 bps channels for voice,

 

multiple logical data links, giving you additional

data, and video communications. It also provides one 16 Kbps

 

bandwithon-demand. Originally, MLPPP was used to

channel for packet-mode signalling, low-speed data and

 

combine two ISDN BRI channels into a single high-

telecommunications services at the OSI Layer 1 level.

 

speed data path, but now is also used anywhere

Similar in function to a DSU/CSU device. NT2 (Network

 

multiple PPP links connect two systems, including

TerminationType 2)—A device at the customer premise

 

async links. This is done with new PPP options and

(user) side responsible for the ISDN network connection and

 

protocols. Also knows as MPPP and PPP Multilink,

for functions such as multiplexing and switching (may be an

 

MLPPP is an effective means of bonding channels for

intelligent device).

 

providing bandwith-on-demand.

NTE (network terminating equipment)—A set of ISDN

 

modem—A communications device that enables a

functions residing at the boundary of the IDN and the

 

computer to transmit information over a telephone

subscriber.

 

line. It converts the computer’s digital signals into

NUI (network user identification)—A unique alphanumeric

 

analog signals to send over a telephone line and

number provided to dial-up users to identify them to packet-

 

converts them back to digital signals at the receiving

switched networks world-wide. The number is used for

 

end. Modems can be internal and fit into an

network access and billing.

 

expansion slot, or external and connect to a serial

O

 

port.

 

 

 

MTA128ST/NT

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Contents Page Trademarks Model MTA128ST/NT S000305C Rev. CRevision Date Description Contents Introduction and Description Product DescriptionFeatures Spid Service Profile IDIsdn BRI Line NT1 ConnectionPin Pin TE SignalInterlace LED Indicators LED P1 LED P2 LED Switch Compatibiltiy LED IndicatorsCommand Interface ConnectorsConnecting your TA Hardware InstallationSafety Warnings Connect the TA to Your PC RS-232 Connection Configuration Utilities Network ConfigurationIntroduction Before You StartCall Control Configuration Voice TEICOM Port Settings Dialing NumbersDCD Drop Time Configuring your TA Page Page Page Page Page Page Page Page MTA128S T/NT Commands and S-Registers AT CommandsAT Commands by Function Digital Data Call Commands a Analog Pots Call CommandsRegisters Register SummaryAT Commands, S-Registers, and Result Codes Using AT Commands to Operate the MTA128ST/NT Result CodesMaking a Call Answering a CallAnswering Automatically Hanging UpAnswering Manually Troubleshooting the TA Specific Troubleshooting SituationsTroubleshoot ing IntroductionDebugging/Logging/Troubleshooting Commands Debugging/Logging/Troubleshooting S-RegistersNone of the LEDs light when the MTA128ST/NTis on Debugging/Logging/Troubleshooting Command Summary ATMTA128ST/NT does not respond to commands MTA128ST/NT dials but cannot make a connection You can place data calls but not voice calls or vice versaMTA128ST/NT cannot connect when answering You cannot place two simultaneous data callsMTA128ST/NT disconnects while online File transfer appears slower than it should beApple Macintosh Compatibility Bonding Using the &, I and + Characters Making PPP/MLPPP ConnectionsSoftware Applications that can Format PPP Data Dynamic Bandwidth Allocation DBADBA Features Bandwidth-on-Demand BOD-S60, S61, S62, and S63 DBA Data ProtocolsPPP/MLPPP Repair Procedures for U.S. and Canadian Customers Warranty, Service, and Tech SupportWarranty Replacement Parts Repair Procedures for International DistributorsQuick Setup Example AppendixAConfiguration ProfilesQuick Setup Factory Profiles Loop Qualification Bearer ServiceAppendix B Ordering Your Isdn Li ne Using Isdn Ordering Codes IOCs M5 previously Generic Data M-1DN J3 previously Generic Data J-1DNCapability S previously Generic Data M Ordering Isdn Without IOCs Appendices Appendices AppendixC FCCand Canadian Regulation FCCCanadian Limitations Notice AppendixD Configuration Methods Firmware-based Configuration UtilityConfiguration via AT Commands Using AT Commands to Configure the MTA128ST/NTSymbol GlossaryGlossary IETFInternet Engineering Task Force PPPMultilink Protocol or MP-is an Internet Glossary TA-Seeterminal adapter Information pages from a central resource. See also Isdn Index Canadian Regulation 56 AppendixUart