The Winlink 2000  (WL2K) radio-email digital network system is intended to greatly extend the ability of the Amateur Radio to provide a public service to the greater community by linking to the Internet email system.  The emphasis is to accomplish this while  providing additional features that are of particular value to amateur users for use in emergency management and everyday use to those in the Amateur service who may not otherwise have  access to the Internet.   It is a priority and commitment of the Winlink Development Team to provide  these public services to the greater  community through Amateur radio.  Below is a discussion of the primary features of the system as it is implemented today. (If needed, a glossary of terms is available.)

A Real-time View of the Winlink 2000 Network:

1. Public (only) Common Message Server (CMS) System (and main menu)
2. Real-Time Monthly Network Statistics
3.  Public (only) PMBO Real-Time Status
4.  Public (only) PMBO Real-Time Status MAP
5.  Telpac Gateway Real-Time Status
6.  Telpac Gateway Real-Time Status MAP
7.  Telpac Registration and Configuration
8.  Winlink 2000 Reporting End-Users (only) in Real-time*

 *Click on the MAP Pin markers to obtain detailed information.  For Positions, click on Pins, callsigns or GRID Squares to track the Winlink 2000 user.

Transparent Inter-working with Internet e-Mail

The primarily purpose of the Winlink 2000 network system is to assist the mobile or remotely located user, and to provide emergency email capabilities to community agencies.  Because of this, WL2K supports a clean simple interface to the Internet SMTP e-mail system.  Using its own , any message sent or received may include multiple recipients and multiple binary attachments.   The radio user's email address, however, must be known to the system as a radio user or the message will be rejected.  This simple Internet interface protocol has an added benefit in case of an emergency where local  services are interrupted and the system must be used by non-Amateur groups as an alternative to normal SMTP email.  Connecting to any one of the WL2K publicly used PMBOs via HF (radio), or the specialized non-public ARES PMBOs, can immediately and automatically connect a local amateur station to the Internet for emergency traffic.  Using MS Outlook or MS Outlook Express, the Paclink mini-email server can replace a network of computers (behind a router) as a transparent substitute for normal SMTP mail.  WL2K uses no external source for sending or receiving Internet email. It is a stand-alone function which interacts directly with the Internet rather than through any external Internet service provider.


Sophisticated Bulletin Distribution

To address the needs of mobile users for near real-time data, WL2K uses an "on-demand" bulletin distribution mechanism. (Note that such bulletins are not the same as traditional AX.25 Packet Bulletins.)  Users must first select requested bulletins from an available "catalog" list managed in Airmail.  When bulletin requests are received by a PMBO, a fresh locally cached copy of the requested bulletin is delivered.  If no freshly local cached version is available, the PMBO accesses the Internet and finds the bulletin which is then downloaded to the PMBO and then sent to the user.  The Global catalog currently includes over 700 available weather, propagation, and information bulletins, including, instructions for using the system, World  news, and piracy reports.  All WL2K PMBOs support a single Global catalog which insures users can access any bulletin from any PMBO.  Bulletins can contain basic text, graphic fax or satellite images, binary or encoded files like GRIB or WMO weather reports.  Local processing is used to re-process images to sizes suitable for HF Pactor transmission.  The system prevents bulletin duplication and automatically purges obsolete time-sensitive  weather bulletins and replaces them with the current version. 

The system also has the ability to contain bulletins with attachment information which is local to each participating PMBO.  This is especially useful for the non-public ARES PMBO which may house valuable procedural information pertinent to complex information or instruction needed by specific agencies  in any community emergency.


Access to Radio Messages with a WEB Browser

There are times when radio users needs to receive (or send) messages when separated from their radio access.  This frequently occurs on cruising yacht where they are unable to operate in port.  By visiting an 'Internet café' or by any other access to a WEB browser, an amateur can read any of his pending messages or originate new ones.  The WEB Browser Access is limited to text-based messages without the use of bulletins or file attachments.  Of course, WEB Browser access to messages is password protected.

Access to Radio Message with Telnet

Airmail provides a super-fast replica of WL2K radio operations while directly connected through the Internet to one of the participating network station (PMBO) telnet servers.  This method of obtaining messages over the Internet allows multiple attachments, catalog bulletins, and all other Winlink 2000 services normally available over radio channels, but at Internet speeds.  In order to use this service, a user must currently be listed as a radio user, and obtain the password for each PMBO Telnet server used.  Both Telpac, Paclink and Airmail support the Telnet client service to over 25 Winlink 2000 Telnet servers.
 

APRSLink: A short message system via the Automatic Position Reporting System (APRS)

The Winlink Development Team (WDT) is always looking for different ways to move messages from one point to another. After the Amateur Radio response to recent disasters, Bob Bruninga, WB4APR, presented the idea of using APRS (Automatic Position Reporting System) to enable mobile and remote APRS users to access their Winlink e-mail accounts under emergency or unusual conditions. In response, the WDT developed APRSLink.

APRSLink monitors all APRS traffic gated to the worldwide internet and watches for special commands that allow APRS users to:

• read short e-mail messages sent to their (callsign@winlink.org) account
• send short e-mail messages to any valid e-mail address or Winlink 2000 user
• perform e-mail maintenance (List, Kill, Forward, Reply, etc.)
• receive notices of pending Winlink e-mail via APRS messages
• query the APRSLink server for information on the closest Telpac or PMBO

With the addition of APRSLink, APRS users now have access to full e-mail capability—albeit, only short messages—from almost anywhere; an APRS-enabled radio or APRS client software and a path to an APRS IGate are all that is required. This link between Winlink and APRS should be useful to Amateur Radio operators who find themselves in emergency or unusual circumstances but need access to an e-mail link into or out of the area.  Learn more.

See http://www.winlink.org/aprslink.htm for additional information.

Reduction in Use of the HF Radio Spectrum

One of the most important objectives in the eyes of the Winlink development team was to reduce the use of the HF spectrum to only that required to exchange messages with a user, and to do that at full "machine" speeds.  The HF spectrum is very crowded, and limiting the forwarding of messages between WL2K PMBOs to the Internet, a great deal of radio air time is eliminated, making the time and spectrum available to individual users either for message handling or for other operations.  Efficient use of the Amateur Radio spectrum is paramount in the WL2K process.  The Winlink development team is continually striving for more effective enabling technologies to accomplish more efficient communications through Winlink 2000.  We welcome ideas, criticisms, complaints, compliments  and  suggestions that will improve the Winlink 2000 system.
 

Multiple Address Messaging

Messages handled by WL2K may have any number of addressees labeled either 'To:' or 'Cc:'  and may mix any combination of radio and Internet SMTP style addresses.  "Bcc" messages from the Internet are optionally accepted by the  Winlink user, but are converted to normal "Cc" for legal reasons.  The Winlink 2000 messaging system uses  the SMTP email format for both messages to the Internet and messages to other radio users.  However, in certain circumstances, only the call is needed for a Winlink 2000 radio user to email another radio user.  Messages addressed to calls not known to the WL2K system are not accepted.


Transparent File Attachments

Multiple binary or text-based file attachments of any type or number may be attached to a message by simply selecting the file to be sent from a Windows selection dialog in the user's HF AirMail or the Winlink 2000  VHF/UHF Paclink server with Outlook or Outlook Express.   Email message attachments sent through the Winlink 2000 system must be limited in size.  User are provided an option to allow this limit to be determined (see below, "user selectable preferences.")   When using the default B2F format, the  protocol chosen by the user usually determines the file size of an attachment. A user may also turn off the ability to receive file attachments.  Certain file attachment types are blocked from the system for the protection of the user from virus attacks.


Elimination of the Need for a "Home PMBO " with the use of "Intelligent Routing"

One of the primary design objectives of Winlink 2000 was to eliminate the need for any user to designate any  specific "home" participating Winlink 2000 "PMBO" network station.  Winlink 2000 (WL2K)  uses a message routing system the makes note of which Winlink PMBO stations a user has connected  over the past 90 days.  Whenever a message is received for a user, it is forwarded to these specific PMBOs.  When the message is read at any one of these PMBOs, a notice is automatically sent to the others  indicating that the message was delivered, thereby, allowing it to be removed from the system.  When a user stops using any specific PMBO for 90 days, messages will no longer be sent to that specific PMBO.   

If a PMBO is used for the first time, the system makes note of it and forwards all pending messages to that PMBO.   The next time the user connects to that PMBO, all of his pending messages will be there.  This is of great benefit to mobile amateurs such as RVers, cruising vessels, and amateurs in remote locations that can only reach the network via HF (radio.)  Users become known to the system simply by connecting to any WL2K PMBO.


Using a Client Program to Access the System

This is a great strength of the Winlink 2000 (WL2K) system.  By using several optional easy-to-use,  sophisticated programs at the user's station, a much more friendly and error-free interface is provided to the user and more features and services are supported than with the traditional teleprinter-style keyboard interface.  This also reduces the connect time on an HF connection where the spectrum is so valuable, allowing more users to access a given PMBO than is possible in keyboard mode.  Advanced formats may be implemented easier with the use of sophisticated client programs such as Airmail or Paclink with Outlook or Outlook Express client programs. Such user client interfaces allowing the same messages to be compressed for shorter transmission times.  It also allows messages to be written off the air so that the shortest, most efficient time is spent on the radio transferring data at speeds impossible to obtain by composing messages in real-time while on the air. As with any other email usage, off-line composition of messages is the norm.

There is a terminal mode for interactive keyboard commands, allowing a terminal rather than computer-based software to connect to a PMBO.  This method discouraged, but may be used for the listing and deletion of messages only.   On HF radio, the client of choice is the  Airmail program written and supported by Jim Corenman, KE6RK.  This is a very elegant user program that supports all of the features of WL2K as well as many other digital modes and is provided for amateur use at no charge.  For VHF/UHF "last mile" communications over AX.25 packet, both Airmail and the new Winlink 2000 Paclink server with single or multiple Outlook and Outlook Express clients  may be used, depending on the required application.


The  Winlink 2000  VHF/UHF Telpac node & Paclink server modules for Expanded Packet Radio Access.

Winlink 2000 Telpac is a new mechanism for delivering mail from the Winlink 2000 system to the wireless ham user.  "Telpac" stands for TELnet-PACket Bridge and allows the Winlink 200 user to employ VHF/UHF Packet mode with the B2F protocol to take advantage of  "last mile" coverage.  Telpac is optimized to easily interface Winlink 2000 to conventional  VHF/UHF Packet users, and when used with the Paclink server and Outlook or Outlook Express single or multiple clients, provides the end-user with all the Winlink 2000 feature sets.  Telpac may also interface with the AirMail packet client module. 

Telpac efficiently links conventional amateur AX.25 packet to Winlink 2000 's Telnet Servers and uses the AGW Packet Engine which supports virtually all Packet TNCs (including BayCom and sound cards).  TNCs can be remote and also shared with other AGW Packet Engine applications.  Telpac is simple to set up and run and requires a minimum of computer and radio equipment. The Telpac software runs independently from the more complex  Winlink  2000  Network MBO (PMBO) software,  and will run on virtually any Windows computer. 

Telpac  is ideal for  a  temporary emergency  management setup or  any other  unattended  remote location where it can deliver reliable wireless communication to the “last mile.”   Telpac with Paclink uses the B2F compressed binary format which provides this communications link with all the features within Winlink 2000.  To download the Telpac software with installation instruction  or just read about Telpac, click here.   A view of the existing Telpac  real-time status , and a real-time Telpac map is available.
 

The Winlink 2000 Paclink email server with MS Outlook, MS Outlook Express, Netscape, or Eudora mail clients  is a complementary "other end" for the use of Telpac.   When used with Telpac on VHF/UHF Packet, Paclink  serves as a local "ISP" or email server  which takes advantage of already existing email agents such as Microsoft's Outlook or Outlook Express.  When used with Telpac, Paclink is extremely useful for communicating over the  "last mile" without the use of expensive modems.  A single Paclink server module may serve an entire network of computers hosting MS Outlook or MS Outlook Express as a transparent alternative to normal SMTP email connectivity to the Internet.  This application is extremely valuable to emergency management agencies where other means of Internet connectivity have been displaced.  To download a self-extracting file of the Paclink software and installation guide, or just read about Paclink,  click here.

Presentations and further information may be found here.


User Selectable Preferences

Using Airmail's Options Message form,  an individual user may send automatic 'service' messages to any WL2K PMBO that will establish user-definable preferences system-wide.  Such options include the size of acceptable file attachments (down to zero), an alternate email or radio address for temporary message forwarding, Bcc messages coming from Internet as well as other options.


System Wide User Notices

The WL2K network administrator may post notices that are delivered to all individual WL2K users as a private message. This is a valuable tool for notifying users of system changes, outages, software upgrades, emergencies, etc. 


Support for an Optimal Number of Participating Winlink PMBOs

The WL2K system will support an optimal number of individual participating PMBOs.  The only requirements are an up-to-date PC, access to Internet via a full-time connection, and Pactor (packet optional)  radio facilities. (Pactor is used on HF, AX.25 packet on VHF/UHF, and both employ the B2F compressed binary format.   A current list of PMBOs is available.  For those who are not interested in becoming a full-time PMBO, the Telpac option may be in order.  In addition to the "standard and public" PMBOs, there are also community ARES® PMBOs continually being deployed.


Rapid Delivery of Messages to the Amateur Operator Anywhere in the World 

The Internet is used to forward messages between WL2K PMBOs.  In the beginning, this was a subject of considerable controversy, but it prevailed by providing two design objectives:  It minimized the use of HF spectrum and it insured the rapid delivery of messages to amateur radio users anywhere in the world.  While the argument was frequently made that 'this is not ham radio', for the user on his sailboat in the middle of the Pacific or amateur in an ARES community service that suddenly found himself in a live emergency, (or even in a normal communication,)  it was and still is a significant benefit.  For most, the Internet is now a part of  everyday life and rather matter-of-fact.  For amateur radio, it is an important tool to be embraced and utilized to everyone's advantage.  As the Internet gained credibility and World-wide acceptance, this argument became history in all but the most oppressive regions.  In addition, because of its relationship with the Internet, and its ability to replace normal Internet connectivity  when  links on the Internet fail, Winlink 2000 is finding itself being used extensively by those involved with Emergency Preparedness.

Certainly the system cannot exist without amateur radio and the view the design team has taken is that the system should make public service a priority.  In other words, does a design objective make the system more useful or attractive to the amateur radio user?  We believe that embracing the Internet and its universally adopted email system is critical to the success of our ability to provide a tremendously valuable public service.  Remember, the same arguments were made about the handkey versus the bug, and the bug verses the electronic keyer, and the electronic keyer verses the keyboard.  Likewise, this same argument was brought in focus with Single Sideband when Amplitude Modulation was the norm.  As amateurs, we must keep growing and contributing to survive by illustrating we are proactively seeking the best technologies and techniques for our hobby.  Public service to the larger world community is paramount, and we must continue to progress with digital communications in order not to appear antiquated by the larger community. An excellent statement supporting this concept was recently provided in an address by the former Chief Engineering and Technology  for the Federal Communications Commission.

Currently, The Winlink Development Team continues to explore enabling technologies and processes  for opportunities to enhanced the system's functionality.   The latest effort is toward enhancing the ability of the network to accomplish a more secure emergency prepared, radio efficient system for communicating, Worldwide.

"FastLink," Connectivity for Winlink 2000 Participating Stations (PMBOs)

 Developed by Vic Poor, W5SMM, of the Winlink development team, FastLink was employed on September 9th, 2002.    FastLink provides the ability to transfer messages through the system at near real-time speed.  This means a message sent from an Internet recipient to a Winlink user though the designated participating Winlink stations (PMBOs) will reach these stations immediately and be ready for pickup by the user moments after it was sent.  Likewise, a message sent from a Winlink user to an Internet recipient or another Winlink user will reach its destination immediately.  In this context,  "immediately," refers to seconds, depending on the speed of the links, traffic on the Internet, etc.

In order to employ FastLink, the Winlink PMBO must have a full-time Internet connection available.  Please go to the Winlink Stations list to review those FastLink PMBOs.  All USA PMBOs utilize are FastLink PMBOs.

How much impact does this have on the Winlink 2000 user?   Because FastLink allows the system to flow in a real-time mode, it makes functions such as  position reporting and requests much  more efficient.  FastLink also makes "near real-time chat" possible between Winlink users, or a Winlink user and an Internet In other words, a Winlink user could send a message to its destination and have a response back before logging off the PMBO.  This, of course, assumes that those receiving these messages are there to immediately reply, and that all links are there while this is taking place.  Obviously, a dial-up Internet recipient would need to be on-line at the time.  FastLink will also certainly assist the Winlink WEB Access and Airmail Telnet Client users, greatly.  FastLink puts Winlink 2000 in a leading position for radio email.  FastLink also has  enhanced emergency management implications. 

Express Participating Network Stations

In addition to employing the "FastLink" methodology, some of the Winlink 2000 participating network stations (PMBOs) also restrict their protocols to Pactor II (400 to 800 bps) and Pactor III (1400 to 3600 bps.)   In doing so, these PMBOs typically have a much higher ratio of traffic minutes and message counts to connect times than do the PMBOs that also receive  the slower Pactor I (100 to 200 bps)  protocol.   In other words the amount of traffic that is passed with an Express PMBO is much greater for an equivalent amount of connect time with approximately the same number of connections.  On average, this translates to a Pactor 1 station downloading an 80,000 byte file in approximately 80 minutes while on Pactor 3, the same download takes approximately 6 minutes.

With the popularity of the faster Pactor Protocols and the shrinking number of Pactor I stations using the Winlink 2000 system, more enhanced features may be brought into the system for an ever-increasing number of  users.

A Platform That is Flexible Enough to Support Many Additional Services

The integrated nature of the system makes possible other services beyond just simple messaging.  The bulletin services mentioned above is beyond normal messaging,  but WL2K also provides rapid position reporting from anywhere in the World.   This facility is interconnected with the APRS, ShipTrak, and YotReps networks.  It supports weather reporting from cruising yachts at sea and an interconnection with the YotReps network which is used by government forecasters for weather observations in parts of the world where no others are available.  It also allows the maritime user to participate in the National Weather Service's NOAA MAROB a  voluntary marine observation reporting program.  The  'Telpac' module when used with the Paclink client may now provide messaging via VHF/UHF packet for "last mile" communications.  These modules may be employed as convenient portables or replace an entire network as a viable and reliable email outlet alternative. 

User Time Limits

To ensure equitable access to the system individual users are assigned daily time limits on HF frequencies by PMBO sysops.  The default time per any 24 hour period is 30 minutes, however, the use may request more time from the PMBO sysop should it be needed.  Remember, the time limit is individual to each PMBO station.  Utilization of the Pactor II and Pactor III protocols are a great timesaver, allowing the user up to 18 times the volume of messages over that of  Pactor I for the same period of time.


Other Features

The system has a number of other secondary features to help keep it healthy. Extensive traffic reports are collected, the state of individual PMBOs is monitored and reported if it become inactive, and daily backups are performed automatically at all PMBOs as well as the Common Message Servers (CMS) to insure the system integrity.  Security is insured through the vigorous updating of virus definitions and automatic virus screening for all Internet mail and files.  The system has the ability to block any user by both radio (by frequency band) and Internet (by email address) to prevent abuse of the system.  SPAM is controlled through the use of a secure "acceptance list" methodology.
 

User Driven System

The Winlink 2000 system was developed from a long list of user requirements.  With obvious focus on the individual user groups, the Winlink development team continually seeks feature ideas and system concepts from the user community it serves.  Please discuss any ideas that you may have for additional functionality to Steve, K4CJX.