In a national environment with support of number portability, the existing ISUP procedures as specified in Recommendation Q.764 [1] apply with the modifications as specified in this Recommendation.
NOTE ISUP formats and codes are described in Recommendation Q.763 [2].
The addressing method for number portability in a network will have an impact on existing functions and services. The impact is network and implementation dependent and outside the scope of this
Recommendation.
With the introduction of the procedures for number portability as defined in this Recommendation, backwards compatibility with the ISUP according to Recommendation Q.767 is not possible.
In addition to the main text, the following annexes are part of this Recommendation: Annex A describes an alternative addressing method making use of a concatenated addressing format. This addressing method may typically be useful as an intermediate solution in some networks as it may limit the impact on existing functions and services. Annex B describes another addressing method making use of the Separate Network Routing Number Addressing method. It may be used within the network of a service provider. This addressing method may typically be useful in some networks as it may limit the impact on existing network functions and service handling.
Annex C describes the additional network capabilities for Query on Release that may be used within the network of a service provider. These additional capabilities may typically be useful in some networks for network efficiency reasons.
Annex D describes the additional network capabilities for Dropback that may be used within the network of a service provider. These capabilities make use of the procedures for Pivot Routing or Redirection as specified in Recommendation Q.730 [3]. These additional capabilities may typically be useful in some networks for network efficiency reasons.
Annex E describes the procedures f (...abbreviated)