# Migrating to the NCC service

NMS Communications no longer supports ADI call control. If you currently use ADI call control, read this section for information about migrating from ADI call control to the NCC service.

The NCC service provides functions and services formerly performed by the call control portion of the ADI service. The NCC service provides a much-extended, enhanced API for call control. The base model for the NCC service is the ADI service call control model, and enhancements including new states, functions, and events.

The major differences between the NCC service and the ADI service are:

- Ability to query the features a protocol supports

- Concept of line as separate from call

- New states; change in definition of existing states

- Supervised transfer performed differently

- New call hold/retrieve functionality

- New features for sending protocol-specific arguments with each function call

- New parameters; reorganization of existing parameters

- Call must be both disconnected and released