# Supplementary service operation summary

The following table lists the supplementary service operations and the variants those operations support. Operations vary depending on the implementation. In this table, V = isdngen implementation, X = original variant-specific implementation, and VX = both implementations:

Supplementary service operation | ETSI | Q.SIG | NI2 | DMS
--- | --- | --- | --- | ---
Invoke bridge calls | - | X | - | -
Invoke call hold | X | - | - | -
Invoke call retrieve | X | - | - | -
Notify hold | X | X | - | -
Notify retrieve | X | X | - | -
Explicit call transfer | V X | - | - | -
Notify transfer | X | X | - | -
Invoke two channel transfer | - | V | X | X
Notify two channel transfer | - | - | X | -
Release link trunk | - | - | - | X
Invoke call diversion | - | X | - | -
Activate diversion | X | - | - | -
Deactivate diversion | X | - | - | -
Enquire diversion | X | - | - | -
Remind diversion | X | - | - | -
Notify diversion (Q.SIG and ETS 300) | X | X | - | -
Invoke call deflection | X | - | - | -
Activate deflection | X | - | - | -
Deactivate deflection | X | - | - | -
Advice of charge request | X | - | - | -
Advice of charge inform | X | - | - | -
Calling name identification presentation (CNIP) | - | V X | X | X
Connected name identification presentation (CONP) | - | V X | X | X
Calling line identification presentation (CLIP) | V X | V X | X | X
Calling line identification restriction (CLIR) | V X | V X | X | X
Connected line identification presentation (COLP) | V X | V X | X | X
Connected line identification restriction (COLR) | V X | V X | X | X