dPMR
The Alabama Link currently doesn't have dPMR linked. It is a mode we are considering, but still researching the best way to do it.
dPMR or digital private mobile radio, is a Common Air Interface (CAI) for digital mobile communications. dPMR is an open, non-proprietary standard that was developed by the European Telecommunications Standards Institute(ETSI) and published under the reference ETSI TS 102 658.
A simplified version of the dPMR protocol intended for licence-free applications was also published by ETSI under the reference TS 102 490.
dPMR is very similar to NXDN protocol implementation by Kenwood and Icom; both now offer dual-standard equipment (July 2013).
dPMR, NXDN and DMR were all launched at around the same time and there was considerable speculation around the industry as to which standard would "prevail", with many people expecting it to be a Betamax -vs- VHS type war. In reality DMR has seen the greatest uptake, due to the lower infrastructure costs (two voice paths for one base station). In response the dPMR manufacturers have considerably cut infrastructure costs such that for small scale systems dPMR is more cost effective to deploy.
In reality the vast majority of systems deployed are DMR. dPMR however does have a niche market with the advocates citing the greater range offered by the true 6.25khz channel spacing and the better spectral efficiency for congested areas. Therefore neither system has "won" the market, with DMR having a large market share, but dPMR looks like it will be around for many years to come.