Winlink
Table of contents
Put simply, Winlink is a messaging system very similar to Email. Whereas email relies 100% on mail transfer servers, Winlink can operate Peer to Peer or via central server. For some features, a central server is required, but to just pass a message from one station to another, direct peer to peer communication can be used.
The big deal
If you’ve ever tried to play the game of telephone, you’ll notice real quickly how language can sound differently from one person to another. In an environment such as radio where your voice can be distorted or misheard, tools like Winlink save the day! With winlink, you are either able to pass the message, or not. It’s a big deal that you can seamlessly pass complex information at a speed and reliability that a human cannot match.
Some argue that things like Winlink are not really ham radio. However you view it, there is no denying that accurate communication is critical in some scenarios. Some instances where Winlink is critical is in the transmission of medical or other complex supply details.
Winlink during Emergencies
Nobody knows what will happen during a full blown emergency, but one thing is for sure. Clear communication of needs and wants is important. Winlink helps to ensure clear and consice communication.
Getting Started
Winlink is not a program or radio feature, it is a piece of software that your computer or device runs and uses the internet, or radio as the means of communicating Winlink messages. For Windows users, your best bet is to use Winlink Express. For Linux & Mac users it is recommended to use Pat Winlink. View their respective pages for installation and setup guides.
After installation, you will compose messages, send messages, and receive messages. There are 2 types of sending and receiving messages: Winlink Common Message Servers (CMS) or Peer to Peer (P2P). Both have trade offs.
CMS
Using the CMS is really easy if you have a stable internet connection because you can use Telnet. Telnet does not require any radio communication. Your Winlink client connects directly to the Winlink CMS and exchanges messages. This is verry similar to IMAP or POP for Email. You can also use the Winlikn CMS by connecting to a Remote Message Server (RMS) using your radio. A RMS is a radio on a specific frequency (HF, VHF, or UHF) that is listening for specific digital communication in the form of Winlink. This could be using Packet radio, Vara, or other digital means. When you connect to a RMS, the RMS acts as a bridge between the Winlink CMS and you. The RMS is connected to the internet.
P2P
P2P allows two winlink clients to connect to each other and exchange messages. This is great if you are remote and don’t have access to a RMS. It allows you to still gain the bennefits of Winlink without any CMS Server requirements.
Sending a Message
Receiving a Message
From Other Winlink Users
To receive email, you first connect to the Winlink CMS or P2P session. During the session any new messages will show up. in your Winlink Client
From External Users
Once you have your winlink setup, you can receive external email. The sender must address their email to <callsig or alias>@winlink.org. External senders must be on your account’s Allow List.
Allow & Reject lists
To allow external email, you must manage your own Allow list. To interact with your Winlink allow list, you send a message to SYSTEM with the subject WHITELIST. In the text of the email, you include commands on each line. There are 4 different comands. You can include multiple commands, however if you are using LIST, I recommend putting that in its own message.
LIST
To view the state of your Allow List, send a message with the text LIST
TO:
SYSTEM
SUBJECT:WHITELIST
TEXT:LIST
ALLOW
Allow a domain or email to your allow list. You can add an entire domain by only including the domain. Such as gmail.com (HOWEVER you really should not add Gmail as an allowed domain.)
TO:
SYSTEM
SUBJECT:WHITELIST
TEXT:ALLOW: ucares.org ALLOW: [email protected]
REJECT
Reject a domain or email to send winlink messages to you.
TO:
SYSTEM
SUBJECT:WHITELIST
TEXT:REJECT: ucares.org REJECT: [email protected]
DELETE
Remove an entry from your Winlink allow list
TO:
SYSTEM
SUBJECT:WHITELIST
TEXT:DELETE: ucares.org DELETE: [email protected]