This read-only field reports the APS message transport actually in use right now, which normally mirrors the admin-configured cApsConfigMessageTransport value exactly, except in the special case where that config object is set to 'autoSelect' -- in that case this status object is the only place to see which specific transport (dcc, ip, or osc) the device actually chose on its own. An admin who configured autoSelect and wants to know exactly what's happening must check this status object rather than the config object, since the config object in that case only reveals the admin's intent to let the device decide, not the actual outcome. For example, if cApsConfigMessageTransport is set to autoSelect, this status object might report that the device is actually using dcc, revealing the automatic choice that isn't visible from the config side alone.