The following Protocols and Standards are supported by IXI-UMS for working together with the PBX:

ISDN CAPI 2.0

• BRI/S₀ and PRI/S_2M
• Protocols: public (e.g. DSS1, NI1), PBX-networking (e.g. Q-SIG), Supplementary Services (e.g. MWI, Call Transfer)

Voice/Fax over IP

• Signaling: SIP, H.323
  SIP Trunking, SIP PBX, IP Centrex 
• Voice: G.711, GSM 6.10; G.729, Speex
• Fax: T.38, SoftFax

Analogue

• Loop start signaling
• POTS trunk interface

^{Depending on supported protocols and connection possibilities, Supplementary Services (e.g. MWI, Call Transfer) are not provided by all the PBX's unrestrictedly.}