200-Series Remote Access Device Remote Access Server with Integrated WAN Devices Model MTASR3-200 User Guide
User Guide 88301100 Revision A RASFinder 200-Series (Model No. MTASR3-200) This publication may not be reproduced, in whole or in part, without prior expressed written permission from Multi-Tech Systems, Inc. All rights reserved. Copyright © 1998, by Multi-Tech Systems, Inc. Multi-Tech Systems, Inc. makes no representations or warranties with respect to the contents hereof and specifically disclaims any implied warranties of merchantability or fitness for any particular purpose.
Contents Chapter 1 - Introduction and Description Introduction ....................................................................................................................................................... 6 Preview of this Guide .................................................................................................................................. 6 Related Documentation ......................................................................................................................
Chapter 6 - Router Management Introduction ..................................................................................................................................................... 42 Router Management ........................................................................................................................................ 43 Dial-Out .....................................................................................................................................................
200-Series Remote Access Device Chapter 1 - Introduction and Description
RASFinder User Guide Introduction Welcome to Multi-Tech's new RASFinder™ 200-Series, model number MTASR3-200, a Remote Access Server (RAS) for remote dial-in access and LAN-to-LAN routing capability. The RASFinder 200-Series is a remote access device that supports up to three concurrent dial-in sessions and IP or IPX remote access. The RASFinder 200-Series features a 10BaseT or 10Base2 port for local LAN connection, Command Port for configuration, and three internal K56flexTM modems*.
Chapter 1 - Introduction and Description Chapter 5 - Remote Configuration This chapter provides procedures for changing the configuration of a remote RASFinder, located elsewhere on a LAN or at the other end of a modem connection. Chapter 6 - Router Management Chapter 6 describes typical Telnet Client and WEB-browser management of the RASFinder.
RASFinder User Guide TCP/IP (Transmission Control Protocol/Internet Protocol) TCP/IP is a protocol suite and related applications developed for the U.S. Department of Defense in the 1970s and 1980s specifically to permit different types of computers to communicate and exchange information with one another. TCP/IP is currently mandated as an official U.S. Department of Defense protocol and is also widely used in the UNIX community.
Chapter 1 - Introduction and Description The Application Layer protocols are examples of common TCP/IP applications and utilities, which include: • Telnet (Telecommunication Network): a virtual terminal protocol allowing a user logged on to one TCP/IP host to access other hosts on the network, described in RFC 854 ( ftp:// ds.internic.net/rfc/rfc854.txt). • FTP: the File Transfer Protocol allows a user to transfer files between local and remote host computers per IETF RFC 959 ( ftp://ds.internic.
RASFinder User Guide Internet Protocol (IP) IP is the Internet standard protocol that tracks Internetwork node addresses, routes outgoing messages and recognizes incoming messages, allowing a message to cross multiple networks on the way to its final destination. The IPv6 Control Protocol (IPV6CP) is responsible for configuring, enabling, and disabling the IPv6 protocol modules on both ends of the point-to-point link. IPV6CP uses the same packet exchange mechanism as the Link Control Protocol (LCP).
Chapter 1 - Introduction and Description A Typical Network Application A typical application of a RASFinder 200-Series is shown in Figure 1-2. In this application, the LAN port is connected to a TCP/IP LAN. A remote node client is able to dial into WAN 1 on the RASFinder. A PPP client is connected to WAN 2 and a Win95 Netware client is using WAN 3. All three remote users are able to access shared services on the LAN and access the internet via a shared internet port. Internet T1-MUX IP Address = 199.24.
RASFinder User Guide Front Panel The front panel contains three groups of LEDs that provide the status of the LAN connection, link activity, and general status of the RASFinder. The EtherNet LAN LEDs display the activity of the LAN in whether the RASFinder is connected to the LAN, transmitting or receiving packets, and if a collision is in progress. The Link LEDs display the status of the three links that can be connected to the RASFinder with whether a link is ready to transmit or receive serial data.
Chapter 1 - Introduction and Description Back Panel The cable connections for the RASFinder are made at the back panel. Three groups of cables are used on the RASFinder: the Command Port, Link 1 (2 and 3) RJ11, and the EtherNet. The cable connections are shown in Figure 1-3 and defined in the following groups.
RASFinder User Guide Specifications The RASFinder conforms to the following specifications: • Routing Protocols - IP and IPX, and bridging for all others • EtherNet LAN Interface - 10Base-T (twisted pair) or 10Base2 (ThinNet) AUI • WAN Interface - 3 async or sync Links (RS232C/V.35) • Frame relay networks for SLIP, PPP, Async and HDLC Sync devices • Frame relay trunk speeds up to T1/E1 synchronous • Command Port - 19.
200-Series Remote Access Device Chapter 2 - Installation
RASFinder User Guide Introduction This chapter is organized in the way you will unpack and cable your RASFinder. The unpacking section describes the contents of the shipping box and shows how the RASFinder is packaged. The installation procedure describes each cable connection and shows where that cable is connected to the RASFinder. If additional RAM is needed on your RASFinder, a detailed procedure is provided describing how to install a second SIMM.
Chapter 2 - Installation Installation The installation procedure in Table 2-1 is organized so that if you need to open the RASFinder enclosure to install additional RAM, you do this before you connect your cables. Table 2-2 provides procedures on how to add additional RAM. The installation procedure provides the cable connections for up to three WANs, two types of connections for your Ethernet, a short adapter cable to connect to your PC for software loading, and finally your power connection. Table 2-1.
RASFinder User Guide Adding Additional RAM A second SIMM connector is provided for adding additional RAM to the RASFinder. The procedure for adding additional RAM is provided in Table 2-2. Table 2-2. Adding Additional RAM Procedure Step Procedure 1 Ensure that the external power supply is disconnected from the RASFinder. 2 Turn the RASFinder upside down and remove the cabinet mounting screw at the center back of the cabinet. Cabinet Mounting Screw (center, back) Figure 2-3.
200-Series Remote Access Device Chapter 3 - Software Loading and Configuration
RASFinder User Guide Introduction The following loading procedure does not provide every screen or option in the process of installing the MultiRouter software. The assumption is that a technical person with a thorough knowledge of Windows and the software loading process is doing the installation. Loading your Software 1. Run Windows on the PC that is connected to the Command Port of the RASFinder. 2. Insert the MultiRouter 200-Series diskette into the disk drive on the PC connected to the Command Port.
Chapter 3 - Software Loading and Configuration 6. The MultiRouter Setup Installation dialog box appears which states, "Please select a communication port for the setup utility to use." In other words, select which COM port on your PC is connected to the Command Port of the RASFinder. Select the COM port (COM1,COM2,COM3, or COM4) for the setup utility. The default port is COM1. Click on OK when you are satisfied with your selection. 7.
RASFinder User Guide 11. Ethernet: You can enable Auto Learn Network Numbers by leaving the default Yes or you can manually assign the network numbers by clicking on No in the Auto Learn Network Numbers field. If no file server is connected to the Ethernet segment, then this field should be No (recommended). If you enable Auto Learn (Yes), the RASFinder will learn the IPX network numbers from the file server.
Chapter 3 - Software Loading and Configuration 21. The WAN Ports Default Setup dialog box is displayed with all the WAN Ports enabled, Asynchronous mode enabled, the speed set at 115200, and the Modem Type defaulted to Socket Modem K56flex. Each WAN port can be configured independently; e.g., one can dial a specific number, another could answer a call, and the third could dial a different number.
RASFinder User Guide Setting Up Your Remote User Database The remote user database lets you gather information about your remote users. You can add remote users, remove users from the database, or you can edit information in the database. 1. Win3.1 users - From the Program Manager, click on the Remote User Data Base icon. Win95 users - From your desktop, click on the Start button, point to Programs, then MultiRouter, and then click on Remote User Data Base. The Users List dialog box is displayed. 2.
Chapter 3 - Software Loading and Configuration 3. Build your user database by filling in the following fields for each user. User Name The User Name can have as many as 39 characters. All printable characters are permitted with the restriction that no blanks are allowed in the user name. In dial-in and dial-out applications, the user name is treated as a case insensitive string. User Password. The User Password can have as many as 7 characters.
RASFinder User Guide 26 MTASR3-200
200-Series Remote Access Device Chapter 4 - MultiRouter Software
RASFinder User Guide Introduction This chapter describes the RASFinder’s MultiRouter software from an applications standpoint, showing how to make changes in the configuration with recommendations on the impact of any such changes. The major configuration parameters were set when the software was loaded into your PC and the setup configuration was downloaded to the RASFinder at the conclusion of the software installation. The MultiRouter software is designed for the Microsoft ® Windows ® environment.
Chapter 4 - MultiRouter Software IP Setup The IP Port Setup dialog box allows you change the IP routing capabilities, add or delete logical WANs, enable the DHCP server, assign DNS address, and define default routes. The initial routing capabilities were established during the software installation. You can change IP routing parameters by clicking on the Advanced tab and changing, for example, the RIP Response Time or RIP Route Aging Time.
RASFinder User Guide The IP General Setup dialog box controls the timers, DHCP (dynamic Host Configuration Protocol) and Domain Name System (DNS) servers, the default route, filters, and Static Routes. In most cases, you should not have to change any of the timers (i.e., default TTL, reassembly timeout, RIP response time and RIP route aging time). The DNS Resolver is supplied for remote Telnet clients when the router is configured for remote access and the terminal server application is enabled.
Chapter 4 - MultiRouter Software IPX Setup The IPX Virtual Port Setup dialog box is used to control the four frame types and set up the three WAN ports of the RASFinder. The Advanced button opens an IPX General Setup window used to enable or disable IPX routing and auto learn of Ethernet network numbers; also, the distributed name of the RASFinder can be designated here. For most applications, the RIP and SAP default timers should not have to be changed.
RASFinder User Guide Spanning Tree Setup When Bridging is enabled, the Spanning Tree Setup dialog box controls simple transparent bridging between two remote Ethernet LANs. However, if your internetwork contains any loops or redundant links, then the Spanning Tree Algorithm must also be enabled. If you use only the IP and IPX protocols, leave bridging disabled to allow the RASFinder to operate more efficiently.
Chapter 4 - MultiRouter Software WAN Port Setup The WAN Port Setup dialog box controls how each WAN port is configured. If a port is configured for point-to-point operation, then the mode can be either synchronous or asynchronous. If the mode is asynchronous, then the connection method can be either Answering or Dialing. If the connection method is dialing, then a number to be dialed has to be entered in the Dial Number field and the correct modem type designated in the Modem Types field.
RASFinder User Guide Point-to-Point Setup The PPP Port Setup dialog box controls the WAN port protocol, dial on demand, and remote port setup. The WAN port protocol can be either Point-to-Point Protocol (PPP) or Serial Line Internet Protocol (SLIP). Of these two protocols, PPP is the more robust as it allows the end-points to negotiate the use of the link and protocol parameters in a standardized way and also allows for standardized encapsulation of the packets.
200-Series Remote Access Device Chapter 5 - Remote Configuration
RASFinder User Guide Introduction This chapter provides procedures for changing the configuration of a remote unit. Remote configuration allows a PC at one site (local site) to dial a remote RASFinder and change the configuration of that remote unit. Remote configuration can be accomplished either directly through the LAN or remotely using modems. To remotely configure a RASFinder, a local PC needs to be connected to a dial-up line and the MultiRouter software configured to call the remote RASFinder.
Chapter 5 - Remote Configuration If your Modem Initialization String, Initialization Response, or Connect Response values are different from the defaults in the dialog box, refer to your modem user documentation and change the default values to match your modem. Click on OK when you are satisfied with all your selections. 6 You are returned to the Windows program. Start the MultiRouter Configuration program. Windows 3.1x: Double click on the Router Configuration icon in the Program Manager.
RASFinder User Guide LAN-Based Remote Configuration Windows Sockets Compliant TCP/IP Stack The configuration program requires a Windows Sockets compliant TCP/IP stack. Microsoft provides a TCP/IP stack free for Windows for Workgroups 3.11. TCP/IP protocol software must be installed and functional before the configuration program can be used. 1 You must assign an internet (IP) address for the PC and for each node that will be managed by the configuration program.
Chapter 5 - Remote Configuration 6 The MultiRouter Setup dialog box is then displayed. This is the dialog box of the remote RASFinder. You can select any of the Protocol Stacks, Device drivers, or other buttons and change the configuration of the remote RASFinder. Refer to Chapter 4 for a description of the MultiRouter software. For definitions of each dialog box or fields within a dialog box, refer to the on-line helps provided in the software.
RASFinder User Guide 40 MTASR3-200
200-Series Remote Access Device Chapter 6 - Router Management
RASFinder User Guide Introduction A typical Telnet client application, and typical WEB-browser management of the RASFinder are described in this chapter. The RASFinder has a built-in Telnet Server for access through Telnet clients. A typical Telnet client is allowed to configure the RASFinder and its data ports. In addition, the RASFinder can be remotely accessed and configured from anywhere on the Internet through its WEB interface.
Chapter 6 - Router Management Router Management The Router Management Menu provides four functional options in addition to the option of escaping and closing the Telnet session. Dial-Out The Dial-out option (Option 1) on the Router Management Menu enables a Telnet user to configure one of the WAN ports for a dial-out session. The default configuration of 115200 bps, 8N1 can be used for the dial-out session, or the user can specify each parameter for the port (e.g.
RASFinder User Guide Applications The Applications option on the Router Configuration menu allows you to enable or disable various types of servers. Choosing the Applications option (Option 4) in the Router Configuration menu displays the Applications Menu. The Applications Menu displays six server options and allows the user to enable or disable the servers as necessary. Initially, all the server options are enabled.
Chapter 6 - Router Management WAN Device Configuration The WAN Device Configuration option (Option 3 on the Router Management Menu) allows a remote user to gain access to any available WAN port on the RASFinder. The user can select either Port 1, Port 2, or Port 3, depending on what port(s) are currently available.
RASFinder User Guide WEB Browser Management The RASFinder can be accessed from anywhere on the connected Internet via its built-in WEB Browser interface. To enable this function, you must check this option in Other setup. Depending on the rights of the user (read/write, or read only), it is possible to view the current parameters and statistics of the RASFinder as well as configure and download setup changes to the unit.
200-Series Remote Access Device Chapter 7 - Service, Warranty and Tech Support
RASFinder User Guide Introduction This chapter starts out with statements about your RASFinder 2-year warranty. The next section, Tech Support, should be read carefully if you have questions or problems with your RASFinder. It includes the technical support telephone numbers, space for recording your product information, and an explanation of how to send in your RASFinder should you require service.
Chapter 7 - Service Warranty and Tech Support Tech Support Multi-Tech has an excellent staff of technical support personnel available to help you get the most out of your Multi-Tech product. If you have any questions about the operation of this unit, call 1-800-9722439. Please fill out the RASFinder information (below), and have it available when you call. If your RASFinder requires service, the tech support specialist will guide you on how to send in your RASFinder (refer to the next section).
RASFinder User Guide Service If your tech support specialist decides that service is required, your RASFinder may be sent (freight prepaid) to our factory. Return shipping charges will be paid by Multi-Tech Systems. Include the following with your RASFinder: • a description of the problem. • return billing and return shipping addresses. • contact name and phone number. • check or purchase order number for payment if the RASFinder is out of warranty.
Chapter 7 - Service Warranty and Tech Support 4. Answer Y or N to the automatic logoff question. 5. Select a file transfer protocol by typing the indicated letter, such as Z for Zmodem (the recommended protocol). 6. If you select Zmodem, the transfer will begin automatically. If you select another protocol, you may have to initiate the transfer yourself. (In most datacomm programs, the PAGE DOWN key initiates the download.) 7. When the download is complete, press ENTER to return to the File Menu. 8.
RASFinder User Guide About CompuServe In addition to the BBS, Multi-Tech provides support through CompuServe’s Modem Vendor Forum (GO MODEMVEN). Refer to your Compuserve documentation for special operating procedures. About the Internet If you prefer to receive technical support via the Internet, you can contact Tech Support via e-mail at the following address: http:\\www.multitech.com\_forms\email_tech_support.htm Multi-Tech’s presence includes a Web site at: http://www.multitech.
200-Series Remote Access Device Appendices
RASFinder User Guide Appendix A - Cabling Diagrams Command Port Cable COMMAND 12345678 PIN NO. To COMMAND PORT Connector PIN NO. 1 1 2 2 TRANSMIT DATA (BA) 3 3 RECEIVE DATA (BB) 4 4 5 5 6 6 7 7 8 8 SIGNAL GROUND (AB) To DTE Device (Terminal Device; e.g.
Appendices Appendix B - Script Language The script file can be used to automate certain operations. The script file is a text file containing a sequence of commands. The structure of a script file is succinctly expressed by the following grammar.
RASFinder User Guide Argument to procedures can be passed by value or address. To pass an argument by address, prefix the argument name in the formal parameter list by the keyword VAR; otherwise the argument is passed by value. Only variables can be passed by address. Expressions like A+B, where A and B are integer variables can be passed by value but cannot be passed by address.
Appendices Appendix C - Regulatory Information FCC Declaration NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a residential installation.
RASFinder User Guide 5. The telephone company may make changes in its facilities, equipment, operations, or procedures that could affect the operation of the equipment. If this happens, the telephone company will provide advance notice in order for you to make necessary modifications in order to maintain uninterrupted service. 6. If trouble is experienced with this equipment (the model of which is indicated below) please contact MultiTech Systems, Inc.
Appendices Canadian Limitations Notice Notice: The ringer equivalence number (REN) assigned to each terminal device provides an indication of the maximum number of terminals allowed to be connected to a telephone interface. The termination of an interface may consist of any combination of devices subject only to the requirement that the sum of the ringer equivalence numbers of all the devices does not exceed 5. Notice: The Industry Canada label identifies certificated equipment.
RASFinder User Guide European Community Directives The CE mark is affixed to the enclosed MultiTech product to confirm compliance with the following European Community Directives: Council Directive 89/336/EEC of 3 May 1989 on the approximation of the laws of Member States relating to electromagnetic compatibility; and Council Directive 73/23/EEC of 19 February 1973 on the harmonization of the laws of Member States relating to electrical equipment designed for use within certain voltage limits; both amended
Appendices Appendix D - AT Command Summary This section summarizes your modem’s AT commands. For detailed information on the commands, download ZPXHELP.EXE from the Multi-Tech BBS (see “Call the Multi-Tech BBS” in Chapter 3). AT Commands Command: +++AT Escape Sequence Values: n/a Description: Puts the modem in command mode (and optionally issues a command) while remaining online. Type +++AT and up to ten command characters, then press ENTER. Used mostly to issue the hang-up command: +++ATH.
RASFinder User Guide Command: Ds Values: Default: Description: Dial s = dial string (phone number and dial modifiers) none Dial telephone number s, where s may up to 40 characters long and include the 0–9, *, #, A, B, C, and D characters, and the L, P, T, V, W, S, comma (,), semicolon (;), !, @, ^ and $ dial string modifiers. Dial string modifiers: L Redial last number. (Must be placed immediately after ATD.) P Pulse-dial following numbers in command . T Tone-dial following numbers in command (default).
Appendices Command: Ln Values: Default: Description: L0 L1 L2 L3 Monitor Speaker Volume n = 0, 1, 2, or 3 2 Select low volume. Select low volume. Select medium volume. Select high volume. Command: Mn Values: Default: Description: M0 M1 M2 M3 Monitor Speaker Mode n = 0, 1, 2, or 3 1 Speaker always off. Speaker on until carrier signal detected. Speaker always on when modem is off-hook. Speaker on until carrier is detected, except while dialing.
RASFinder User Guide Command: Xn Values: Default: Description: X0 X1 X2 X3 X4 X5 X6 X7 Result Code Selection n = 0–7 4 Basic result codes (e.g., CONNECT); does not look for dial tone or busy signal. Extended result codes (CONNECT 56000 V42bis, CONNECT 33600 V42bis, etc.); does not look for dial tone or busy signal. Extended result codes with NO DIALTONE; does not look for busy signal. Extended result codes with BUSY; does not look for dial tone. Extended result codes with NO DIALTONE and BUSY.
Appendices Command: &Jn Values: Default: Description: &J0 &J1 Auxiliary Relay Control n=0 0 The auxiliary relay is never closed. Not supported—responds ERROR. Command: &Kn Values: Defaults: Description: &K0 &K3 &K4 Local Flow Control Selection n = 0, 3, or 4 3 Flow control disabled. Enable CTS/RTS hardware flow control. Enable XON/XOFF software flow control. Command: &Mn Values: Defaults: Description: &M0 &M1 Communications Mode n=0 0 Asynchronous mode. Reserved—responds ERROR.
RASFinder User Guide Command: \Gn Values: Default: Description: \G0 \G1 Modem Port Flow Control n=0 0 Returns an OK for backward compatibility with some software. Not supported—responds ERROR. Command: \Jn Values: Default: Description: \J0 \J1 Data Buffer Control n=0 0 Enable data buffer—serial port speed is independent of connect speed. Not supported—responds ERROR.
Appendices Command: %B Values: Description: View Numbers in Blacklist n/a If blacklisting is in effect, this command displays the numbers for which the last call attempted in the previous two hours failed. In countries that do not require blacklisting, the ERROR result code appears. Command: %Cn Values: Default: Description: %C0 %C1 Data Compression Control n = 0 or 1 1 Disable V.42bis/MNP 5 data compression. Enable V.42bis/MNP 5 data compression.
RASFinder User Guide 68 MTASR3-200
200-Series Remote Access Device Glossary of Terms
RASFinder User Guide A Access: The T1 line element made up of two pairs of wire that the telephone company brings to the customer premises. The Access portion ends with a connection at the local telco (LEC or RBOC). Accunet Spectrum of Digital Services (ASDS): The AT&T 56K bps leased (private) line service. Similar to services of MCI and Sprint. ASDS is available in nx56/64K bps, where n=1, 2, 4, 6, 8, 12.
Glossary Basic Rate Interface (BRI): An ISDN access interface type comprised of two B-channels each at 64K bps and one Dchannel at 64K bps (2B+D). Bell Operating Companies (BOC): The family of corporations created during the divestiture of AT&T. BOCs are independent companies which service a specific region of the US. Also called Regional Bell Operating Companies (RBOCs).
RASFinder User Guide Channel: A data communications path between two computer devices. Can refer to a physical medium (e.g., UTP or coax), or to a specific carrier frequency. Channel Bank: A device that acts as a converter, taking the digital signal from the T1 line into a phone system and converting it to the analog signals used by the phone system. A channel bank acts as a multiplexer, placing many slowspeed voice or data transactions on a single high-speed link.
Glossary Dataphone Digital Service (DDS): A private line digital service that offers 2400, 4800, 9600 and 56K bps data rates on an inter-LATA basis by AT&T and on an intra-LATA basis by the BOCs. Data Service Unit (DSU): A device that provides a digital data service interface directly to the data terminal equipment. The DSU provides loop equalization, remote and local testing capabilities, and a standard EIA/CCITT interface. Dedicated Line: A communication line that is not switched.
RASFinder User Guide ESF Error Event: A T1 error condition that is logged when a CRC-6 error or an out-of-frame (OOF) error occurs. Ethernet: A 10-megabit baseband local area network that allows multiple stations to access the transmission medium at will without prior coordination, avoids contention by using carrier sense and deference, and resolves contention by using collision detection and transmission. Ethernet uses carrier sense multiple access with collision detection (CSMA/CD).
Glossary Frame Relay Forum: A non-profit organization of 300+ vendors and service providers, based in Foster City, CA, that are developing and deploying frame relay equipment. Frame Relay Implementors Forum: A group of companies supporting a common specification for frame relay connection to link customer premises equipment to telco network equipment. Their specification supports ANSI frame relay specs and defines extensions such as local management.
RASFinder User Guide ISDN (Integrated Services Digital Network): An International telecommunications standard for transmitting voice, video and data over a digital communications line. ISDN is a world-wide telecommunications service that uses digital transmission and switching technology to support voice and digital data communications. Frame relay was partially based on ISDN’s data link layer protocol (LAPD).
Glossary Long Haul Communications: The type of phone call reaching outside of a local exchange (LE). M Management Information Base (MIB): A database of network management information used by the Common Management Information Protocol (CMIP) and the Simple Network Management Protocol (SNMP). Megacom: An AT&T service with a normal WATS line (typically T1) between the customer premise and the AT&T serving class 4 CO are the customer’s responibility. MegaLink: BellSouth’s leased T1 service.
RASFinder User Guide Out-of-band: Signaling that is separated from the channel carrying the information (e.g., the voice/data/video signal is separate from the carrier signal). Dialing and various other “supervisory” signals are included in the signaling element. Contrast “In-band” signaling. Out of Frame (OOF): A T1 alarm condition that is logged on the loss of 2, 3 or 4 of 5 consecutive FT framing bits. P Packet: 1.
Glossary Q Quantizing: The process of analog-to-digital conversion by assigning a range, from the contiguous analog values, to a discrete number. R Random Access Memory (RAM): A computer’s primary workspace. All data must be stored in RAM (even for a short while), before software can use the processor to manipulate the data. Before a PC can do anything useful it must move programs from disk to RAM. When you turn it off, all information in RAM is lost.
RASFinder User Guide Simple Network Management Protocol (SNMP): TCP/IP protocol that allows network management. Simultaneous Voice Data (SVD): A technology for letting a user send data via a modem, and use a handset to talk to another user at the same time over the same connection. The alternative, making a second call, can be expensive or even impossible. The uses for SVD are telecommuting, videoconferencing, distant learning, tech support, etc.
Glossary Transmission Control Protocol / Internet Program (TCP/IP): A multi-layer set of protocols developed by the US Department of Defense to link dissimilar computers across dissimilar and unreliable LANs. Terminal: The screen and keyboard device used in a mainframe environment for interactive data entry. Terminals have no “box”, which is to say they have no file storage or processing capabilities. Terminal Adapter (TA): An ISDN DTE device for connecting a non-ISDN terminal device to the ISDN network.
RASFinder User Guide W Wide Area Network (WAN): 1. A network that provides communication services to a geographic area larger than that served by a local area network or a metropolitan area network, and that may use or provide public communication facilities. 2. A data communications network designed to serve an area of hundreds or thousands of miles; for example, public and private packet-switching networks, and national telephone networks. Contrast with local area network (LAN).
