Headless javAPRSSrvr described a trial iGate+digi based on javAPRSSrvr v4.1b5. This article wraps up the trial.
javAPRSSrvr is a Java application, and it was evaluated on Win2K, WinXP, Win7, Ubuntu 12.04, and RPi Raspbian.
Most of the trial was conducted on the RPi. A SysV init script was written to run the applications as a user (for security reasons) to automate startup in the event of power failure and other system restarts.
Only a small part (NSRdigi and iGate) of the applications capability was trialled, but probably the parts most used generally.
In all test configurations, radio access was via a KISS TNC using javAPRSSrvr’s native KISS serial support and a FTDI USB/serial adapter. It was tested with a range of TNCs (VK6, Paccomm Tiny-2 Mk-2, MFJ-1270B, TNC-X and OT-USB). The last two are half baked KISS implementations that do not support KISS commands for channel access control.
The most reliable TNC configuration was a TNC-2 with SMACK EPROM (though javAPRSSrvr native KISS support does not support CRC). It was a KISS only TNC that honoured KISS commands to configure equitable channel access, and was not dependent on battery backed memory in the TNC for its startup configuration.
CPU utilisation was quite steady at 14%, apparently independent of traffic.
Traffic was monitored for corruption and latency, no evidence was found of any problems. The system did seems consistently slower than competing systems in ‘winning’ APRS-IS submission of packets heard simultaneously, but that is not a functional limitation.