Winlink

Winlink, also known as the Winlink 2000 Network, is a worldwide radio messaging system that uses amateur-band radio frequencies to provide radio interconnection services that include email with attachments, position reporting, weather bulletins, emergency relief communications, and message relay. The system is built and administered by volunteers and administered by the Amateur Radio Safety Foundation Inc., an American charitable entity and 501c(3) non-profit organization.

Winlink networking started by providing interconnection services for amateur radio. It is well known for its central role in amateur radio Emcomm messaging. The system runs several central message servers around the world for redundancy. A subset of HF gateway stations operate since 2013 as the Winlink Hybrid Network, offering message forwarding and delivery through a mesh-like smart network whenever internet connections are damaged or inoperable. During the past decade it increasingly became what is now the standard network system for amateur radio email worldwide. Additionally, in response to recent needs for better disaster response communications, the network has been expanded to provide separate parallel radio email networking systems for MARS, UK Cadet, Austrian Red Cross, and other communities.

Generally, email communications over amateur radio in the 21st century is now considered normal and commonplace. Email via High frequency (HF) can be used nearly everywhere on the planet, and is made possible by connecting an HF single sideband (SSB) transceiver system to a computer, modem interface, and appropriate software. The HF modem technologies include PACTOR, Winmor, and Automatic Link Establishment (ALE).

Amateur radio users in each country follow the appropriate regulatory guidelines for their license. Some countries may limit or regulate types of amateur messaging (such as email) by content, origination location, end destination, or license class of the operator. Origination of third party messages, i.e., sent to an end destination who is not an amateur operator, may also be regulated in some countries; those that limit such third party messages normally have exceptions for emergency communications. In accordance with long standing amateur radio tradition, international guidelines and FCC rules section 97.113, hams using the Winlink system are advised that it is not appropriate to use it for business communications.

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