A Secondary Station Identification, or SSID, is a number added after the callsign to indicate the function of the station. SSID assignments are slightly different for Winlink and APRS. While there are no hard and fast rules governing SSIDs, the amateur radio community has come to adopt some conventional standards. There are typically a maximum of 15 SSID’s per call sign. The table below shows the typical usage of SSID’s.
SSID Conventions
| SSID | Packet, Winlink, etc | APRS |
|---|---|---|
| -0 | Home station. (1) | Your primary station usually fixed and message capable |
| -1 | Home station personal mailbox. (2) | generic additional station, digi, mobile, wx, etc |
| -2 | Gateways | generic additional station, digi, mobile, wx, etc |
| -3 | Full service BBS's. (3) | generic additional station, digi, mobile, wx, etc |
| -4 | Network Nodes. (4) | generic additional station, digi, mobile, wx, etc |
| -5 | Console, keyboard or printer | Other networks (Dstar, Iphones, Androids, Blackberry's etc) |
| -6 | Conference Bridges | Special activity, Satellite ops, camping or 6 meters, etc |
| -7 | Crossband digipeaters and KA-Nodes | walkie talkies, HT's or other human portable |
| -8 | Crossband digipeaters | boats, sailboats, RV's or second main mobile |
| -9 | Mobiles | Primary Mobile (usually message capable) |
| -10 | Winlink 2K | internet, Igates, echolink, winlink, AVRS, APRN, etc |
| -11 | unassigned | balloons, aircraft, spacecraft, etc |
| -12 | unassigned | APRStt, DTMF, RFID, devices, one-way trackers*, etc |
| -13 | unassigned | Weather stations |
| -14 | unassigned | Truckers or generally full time drivers |
| -15 | Downlink address when exiting the far end of a network connection. | generic additional station, digi, mobile, wx, etc |
1) Note: “-0” not needed – automatically presumed if no SSID.
2) Usually a TNC-based PBBS
3) Those that forward mail and bulletins
4) Having two or more radio ports that perform routing functions via TCP/IP, NetROM, etc. Can be combined with BBS’s that also perform routing.