A Winlink Glossary

802.11
A wireless data communications standard specified by the IEEE. Also known as WiFi. Amateur radio operators modify consumer 802.11 equipment to use power levels permitted under the amateur radio rules (FCC Part 97), when it is often called HSMM (High Speed MultiMedia). In Europe, 802.11 networks are often referred to by the term HAMNET.

AFSK
Audio Frequency Shift Keying.

AGC
Automatic Gain Control. An automatic circuit in a receiver, or in firmware in some receivers and modems, used to maintain a constant level of audio gain output even though the incoming analog signal may be varying in strength.

AirMail
The oldest and most popular client software for Winlink 2000 system users. It provides access to the WL2K system via telnet, VHF/UHF gateways, or HF Pactor gateway stations. It is a stand-alone program providing peer-to-peer connections between AirMail stations, propagation forecasting, a bulletin catalog, and canned forms for WL2K and MARS services. AirMail is a third-party program written and supported by Jim Corenman, KE6RK (see www.airmail2000.com) and is free of charge for amateur and MARS use.

AM
Amplitude Modulation. An old, broad bandwidth type of voice modulation used by shortwave and familiar 'AM' broadcast stations. Audio fluctuations cause changes in wave amplitude.

AMTOR
Amateur Teleprinting Over Radio. Uses error correction techniques (ARQ and FEC). Similar to marine SITOR in format.

ARQ
Automatic Repetition on Request. An error correction mode used in AMTOR, SITOR and PACTOR. An interactive mode requiring feedback from a receiving station as a communication is sent.

ARRL
The American Radio Relay League. The US national organization for amateur radio.

AX.25
The signaling protocol used by Winlink 2000 for passing data on VHF/UHF Packet channels. Winlink 2000 uses the AX.25 Pactor protocol to carry its B2F Format.

Band
A designated range of frequencies within which operation is authorized.

Bandwidth
The effective or usable range of a resonant circuit, bandpass filter, transmitted signal, or antenna. For an antenna, the frequency range is either side of a resonant frequency where the SWR is below 2 to 1.

Blacklist
A list of email addresses or domains that will be rejected when sending mail inbound to a WL2K user from the internet. Each WL2K user account has a Blacklist and a Whitelist. The entire Spam-Control mechanism is sometimes referred to as the "WL2K Whitelist". Also, "reject list". See Whitelist, Spam.

CMS
The Common Message Servers (CMS) are the common coordinating engines at the heart of the Winlink 2000 "star" Network configuration. They coordinate the traffic between network radio server stations (RMS gateway stations), and provide the e-mail, telnet, bulletin and position reporting services. All this is done over the Internet using TCP/IP for speed, and to use the amateur radio spectrum efficiently. Winlink gets synergy of both the internet and radio spectrum without suffering connectivity failures or crowding the amateur bands. Each of the existing Common Message Servers is a mirror image of the other, providing continual redundancy should one of these servers become inoperative. The CMS Telnet server is compatible with AirMail, Paclink, Outpost, Windows Telpac, Telpac Node/LinuX, Linux RMS Gateway, RMS Packet, and RMS Pactor gateway software. There can be up to five active CMS sites. The sites are geogaphically distributed worldwide, are synchronized, and any single site is capable of handling all traffic for the entire network.

Co-located
Running on the same computer, LAN, or over short distance Ethernet links. Or, located at the same site in close proximity.

CW
Continuous Wave. Also known as Morse code. It is a mode where the radio carrier is simply switched on and off with no modulation.

D-Star
Digital Smart Technologies for Amateur Radio. This is a digital voice and data protocol specification developed by the Japan Amateur Radio League. D-Star is one of the first on-air standards to be widely deployed and sold by a major radio manufacturer that is designed specifically for amateur service use. D-Star compatible radios operate on VHF and UHF and microwave amateur radio bands. In addition to the over-the-air protocol, D-Star also provides specifications for network connectivity, enabling D-Star radios to be connected to the Internet or other networks and provisions for routing data streams of voice or data via amateur radio callsigns. The D-Star DD mode (Digital Data) is particularly useful as a high-speed substitute for VHF or UHF packet radio on short-haul WL2K user connections, or as medium-distance high-speed TCP/IP wireless data links.

Demodulator
A device used to decode or remove intelligent meaning from a radio or audio signal. Sometimes TNCs are referred to as a modulator/demodulator or modem.

Duplex
A type of radio communication using two-way simultaneous traffic on two channels or frequencies. Half Duplex indicates commuication on one frequency where one side then the other transmits. The telephone is full duplex. Most two-way radio links, except when using VHF/UHF repeaters, are half-duplex.

FAX
Facsimile. A mode of transmission used to transmit pictures, documents, and visual data. Used for weather maps and satellite pictures.

FCC
Federal Communications Commission. The US regulatory agency for radio and other broadcast communications.

FEC
Forward Error Correction. A data correction technique used in AMTOR, SITOR and PACTOR.

FM
Frequency Modulation. A transmission mode of high clarity of audio, normally used at VHF and UHF frequencies. Audio fluctuations cause changes in wave frequency.

FSK
Frequency Shift Keying. A special transmission technique used in HF RTTY and some PACTOR modes. Two frequencies, a high/low pair called "mark" and "space", are used in alternating fashion to transmit encoded data.

Ham
The affectionate term for a licensed amateur radio operator.

Health & Welfare
Also called H&W. Type of traffic on a net where information on the well-being of a person or property is exchanged.

HF
High Frequency - Frequencies between 3 and 30 megahertz.

LSB
Lower Sideband. One mode used in single sideband (SSB) transmissions. The upper sideband an the carrier are suppressed. LSB is the 'standard' voice mode used in amateur radio below 10 MHz.

Manager programs
The term used for any of the programs that support the management of the WL2K system. Manager programs are only used by System Administrators or some sysops.

MAYDAY
International voice distress signal used only in cases involving grave and imminent danger to life or property where immediate assistance is required. MAYDAY is spoken three times prior to the distress message.

MID
A message identification number that uniquely identifies each message that flows into and out of the Winlink 2000 system.

MBO
An abbreviation for 'mailbox'. It applies specifically to radio-based mailboxes operated by amateurs.

Modem
See TNC below.

Modulator
A device used to encode or add intelligent meaning to a radio or audio signal. Sometimes TNCs are referred to as a modulator/demodulator or modem.

Net
A radio network. A group of operators who have agreed to meet, at a certain time and frequency to exchange information or move traffic.

Packet Radio
A digital mode of transmission using the protocol called AX.25. Most popular on VHF and UHF frequencies, but also used on HF. Winlink uses this mode for short-haul user links to RMS Packet gateway stations on VHF and UHF frequencies.

Paclink
The latest version of this client/server radio email application is named simply "Paclink". Paclink is a streamlined radio e-mail client with a built-in POP/SMTP server that allows you to use most popular e-mail client programs, like Microsoft Live Mail, Outlook Express and Mozilla Thunderbird. It is a single- or multi-user client. It is exceptionally easy to install and use. Paclink supports telnet (for amateur radio High Speed Multimedia [HSMM], D-Star DD mode, or internet), VHF/UHF packet radio, and HF Pactor radio connections to WL2K servers and the user interface is through any common e-mail client program.

Paclink AGW & Paclink Postoffice
A Winlink 2000 client/server email application that enables the use of a single or multiple computers with email programs such as MS Outlook, MS Outlook Express, Netscape, Eudora, etc. to exchange email via Telnet or VHF/UHF Packet. Paclink AGW utilizes the AGW Packet Engine to drive Packet modems, including computer sound cards. With one single Paclink installation on a LAN, multiple computers running standard email programs may be enabled with radio email when used with the Winlink 2000 network system. Paclink AGW was replaced by Paclink MP.

Paclink MP
A second-generation Winlink client program that replaces Paclink AGW & Paclink Post Office. 'MP' means multi-port. Paclink MP has been replaced by a newer program called simply "Paclink". This software provides client access to WL2K for either a single or multiple users on a LAN with the individual users accessing the system from common email client programs using POP3/SMTP. Paclink will provide priority weighted access to any number of potential WL2K channels including telnet, packet, or Pactor. Paclink MP is particularly useful in EmComm applications.

Pactor 1, 2, 3, 4
The signaling protocols used by Winlink 2000 to carry its B2F format on HF radio channels. Pactor is the invention of SCS GmbH & Co. KG. Pactor 1 is an "open" mode available on many manufacturer's TNCs. Pactor 2, 3 and 4 are proprietary to SCS and only available on SCS PTC range of products.

PMBO
A Winlink 2000 participating network MBO. This term normally applies to the first generation of Winlink 2000 radio mail server software, and its use is replaced by "RMS" or Radio Mail Server. PMBOs or Radio Message Servers, exchange messages with each other through the CMS's in a "star" network configuration via the Internet, and with the end-users over radio, over the Internet using Telnet, or WebMail via this site.

Radial
A 1/4 wavelength tuned wire used in an antenna system to create a counterpoise or artificial RF ground.

Reciprocal License
A license issued by one country to a licensed amateur from another country. These are only issued by countries with mutual agreements.

Repeater
A transmitter-receiver device which received signals and re-transmits them over a wide geographical area. Used on the 10-meter amateur band and above.

RF
Radio Frequency. The frequencies in the electromagnetic spectrum commonly used for transmitting intelligent content. Also used to refer to RF Energy, or energy that alternates polarity at radio frequencies.

RMS
RMS is short for Radio Message Server. The general term "RMS" for 'Radio Mail Server' has replaced "PMBO" for 'Packet (or Pactor) Mail Box Operator'.

RMS Gateway
"RMS Gateway" refers to any RMS station connected to one or more CMS (Common Mail Server) in the "cloud". Or, it can refer to an HSMM or D-Star gateway connecting to any CMS using the Telnet protocol. These stations are "gateways" to the CMS for user (client) stations.

RMS HF
RMS HF was once the name of a Winlink 2000 software application, but has been deprecated. The replacement is RMS Pactor.

RMS HF Stations
"RMS HF Stations" refers generally to all Winlink gateway stations in the high frequency bands, which may run either RMS Pactor, RMS WINMOR, RMS Linux Gateway software, or other HF BBS software. They use either Pactor I, II, III, or WINMOR protocols. This is seen on status reports and maps on the Winlink website.

RMS Packet
A second-generation Winlink 2000 software application that generally duplicates the functions of Telpac with numerous improvements. RMS Packet is a stand alone program that connects AX.25 packet links through to the CMS sites. It is intended to replace Windows-based Telpac and PMBO packet ports. RMS Packet will interface a packet TNC supporting multiple simultaneous connections on a VHF channel or two VHF channels if it is a dual port TNC. Alternatively an RMS Packet instance may optionally interface to a single or multi-port AGW Packet Engine installation. There can be any number of RMS Packet program instances in a single computer running at a site limited only by the computer and site s resources. The programs will run on a Windows 2000 or later operating system.

RMS Packet Stations
"RMS Packet Stations" always refers to VHF or UHF gateway stations in the Winlink network running RMS Packet, RMS Linux Gateway software, or other BBS software. They always use Packet Radio (AX.25) protocol.

RMS Pactor
A second-generation Winlink 2000 software application that provides a gateway for HF Pactor 1, 2, or 3 stations to the Winlink 2000 system's CMS cluster. RMS stations include a computer-controlled HF transceiver, a Pactor modem, and a TCP/IP connection to Winlink CMS servers. Second-generation stations running RMS Pactor are referred to as RMS gateway stations and not PMBOs. Each instance of RMS Pactor will support a single SCS PTC controller (any model) and an HF radio with optional scanning and antenna switching. There can be any number of RMS Pactor program instances in a single computer running at a site limited only by the computer and site's resources.

RMS WINMOR
A second-generation Winlink 2000 software application that provides a gateway for HF WINMOR stations to the Winlink CMS cluster. RMS WINMOR stations are similar to RMS Pactor stations, except they are configured with a sound card interface and the WINMOR TNC, a special 'soft' TNC that implements the WINMOR protocol over radio.

RMS Relay
This is a supplemental program that can provide temporary storage of messages and local routing in the event TCP/IP access to all of the CMS sites is lost. It will normally only be used with co-located RMS Packet and Paclink MP programs in EmComm applications. The relay program becomes active when TCP/IP links are lost to CMS sites. When active it provides temporary message storage and routing. Optionally, it will also exchange messages with a CMS using links to distant RMS HF programs over HF. The RMS Relay program can share the same Pactor controller and radio used by an RMS HF program running on the same computer. (When no TCP/IP connection to a CMS is available, the RMS HF's inbound portal is deactivated, freeing the modem and radio to serve in HF relay service for the local area VHF ports.

RTTY
Radio Teletype. A mode of transmission used to transmit text messages. Uses FSK or AFSK emission types. Mainly used for keyboard-to-keyboard communications.

SAR
Search and Rescue. Special activity to locate and save distressed individuals, aircraft, vessels at sea and remote locations or disaster sites.

SHF
Super High Frequency, a term that generally refers to frequencies higher than Ultra High Frequency (UHF) but below other microwave frequencies.

Simplex
One-way-at-a-time communications on a single frequency. See also Duplex.

SITOR
Simplex Telex Over Radio. A RTTY-like communication mode used to pass text messages. May be run in interactive (ARQ) or broadcast (FEC) mode. Uses special error correction techniques.

SOS
International Morse Code (CW) Distress Signal. Same as MAYDAY for voice.

Spam
A computer term meaning unwanted and unsolicited mail or content. Named after the canned meat product.

Spam Filter
Mechanism to read and sort mail to separate (or destroy) unwanted mail in the incoming stream. WL2k employs several methods, including a "Whitelist/Blacklist" method that each user can control. The user-controlled spam filter for Wl2K users is popularly called the "WL2K Whitelist".

SSB
Single Sideband. A voice radio modulation mode normally used on HF and VHF frequencies. It provides a narrow signal bandwidth for efficient spectrum use compared to AM. Either USB or LSB may be used.

SYSOP
A system operator - the amateur control operator who operates a Radio Mail Server (RMS) gateway station or PMBO.

Telpac
An obsolete Winlink 2000 software application that acts as a gateway between packet radio and the Winlink System via Telnet over any TCP/IP connection, including the Internet and high-speed TCP/IP radio. A Telpac station contains a VHF/UHF transceiver, a radio modem (TNC) and a connection by TCP/IP to a CMS or PMBO.

Third Party Traffic
Message or phone patch traffic passed from a third person or entity via one amateur to another. Between hams in different countries, third party traffic on amateur frequencies is prohibited unless a formal agreement to allow it has been reached between the respective countries.

TNC
Terminal Node Controller. A device that converts a computer's digital signals into audio signals for radio while providing control signals to key the radio and optionally, to change frequencies and other radio functions. Also referred to as a radio modem, modem, or modulator/demodulator. Multi-mode TNCs transmit and copy many digital modes including WXFAX, CW, SITOR, RTTY, NAVTEX, PACTOR, CLOVER, AX.25 packet radio, and others.

UHF
Ultra High Frequency. The band of frequencies above VHF. 300 to 3000 MHz. At 450 MHz, the 70 cm amateur band is considered in the UHF range. 1000 to 3000 is sometimes referred to as SHF or Super High Frequency.

USB
Upper Sideband. One mode of SSB transmission. The carrier and lower sideband are suppressed. This is the normal mode for ham voice transmissions above 10 MHz, and for many digital data modes, regardless of frequency.

VE
Volunteer Examiner. In the US, a licensed amateur, General Class or above, who agrees to give Amateur Radio licensing examinations. VE's must be registered and work with an FCC-approved VEC group to administer examinations.

VEC
Volunteer Examiner Coordinator. A US organization that coordinates VE's administering amateur radio licensing examinations. They must be registered and approved by the FCC.

VHF
Very High Frequency. The range of frequencies from 30 to 300 MHz. They have short-range, near-line-of-sight propagation characteristics.

WARC
World Administrative Radio Conference. Special meetings held by ITU members to determine international radio spectrum usage. The "WARC bands" are the amateur bands on 10, 18 and 24 MHz authorized by WARC-79.

Whitelist
A list of email addresses or domains that will be accepted when sending mail inbound to a WL2K user from the internet. Each WL2K user account has a Blacklist and a Whitelist. The entire Spam-Control mechanism is sometimes referred to as the "WL2K Whitelist". Also, "reject list". See Whitelist, Spam, Spam Filter.

WX
Weather.