A Private Telecommunication Network (PTN) is a network comprising either one PTNX or more than one PTNX interconnected by inter-PTNX connections. This Technical Report is concerned with inter-PTNX connections (IPCs) that are provided by Intervening Networks (IVNs), and the way in which these are handled by PTNXs to provide a platform for inter-PTNX communication. Different types of IVNS can be used to provide IPCs, in accordance with the scenarios indicated in ENV 41006. These are transparent scenarios in that they enable the services of the PTN to operate transparently across an IVN.
Connected PTNXs need to coordinate their use of IVNS, and appropriate standardization is needed to allow networks to be created employing PTNXs and IVNS from multiple vendors. The following points need to be considered:
1. In general, but depending on the type of IVN, procedures and signalling protocols an the PTNXs are needed for the establishment, maintenance and dis-establishment of IPCs. Appropriate standardization of these procedures and signalling protocols is necessary.
2. At the Q-reference point (a conceptual point within a PTNX) channels and PTN call control signalling (QSIG) are defined independently of the type of IVN.
However, at the C-reference point (where the PTNX is connected to the IVN), the representation of the channels and of signalling is dependent on the type of IVN, and on how the PTNXs use the IPCs. Appropriate standardization of these aspects at the C-reference point is necessary.
3. In general, the relationship between a channel at the Q-reference point and its representation at the C-reference point is not static, and procedures and signalling between the PTNXs are needed for the coordination of these relationships. Appropriate standardization of these procedures and signalling is necessary.
4. Appropriate mechanisms need to be standardized for conveying inter-PTNX signalling through the IVN. These will depend on the characteristics of the IPC used.
The aim of this Technical Report is to identify:
i) in addition to PTN call control signalling (QSIG), what needs to be standardized, in order to be able to on PTNX;
ii) techniques, procedures, protocols etc. that are general in that they apply to the use of all (or at least very many) types of IVNs.