VoIP and ENUM

Lennart Maris from the Eindhoven University of Technology published his master thesis on Infrastructure ENUM.

Congratulations, this is a nice piece of work.

In the first part, Lennart gives a very good overview on the status of User and Infrastructure ENUM and VoIP Peering.

He correctly identifies the two main application areas for Infrastructure ENUM:

1. facilitating VoIP interconnection and
2. facilitating number portability.

He then creates 4 implementation models:

1. The closed model,
2. Open Infrastructure ENUM: The email model,
3. The compromise model and
4. Next Generation COIN.

These so called implementation models comprise VoIP interconnection and number portability as the two application areas for Infrastructure ENUM. The main difference between the implementation models is the degree of openness. Roughly there are two approaches for the organizational structure of Infrastructure ENUM: an open and a closed approach. Model 1 & 4 represent the closed approach and model 2 & 3 represent the open approach.

He then made a questionaire of stakeholders in the Netherlands: regulators, operators, vendors and interest groups.

The results are very interesting:

• No seriously considered alternatives for Infrastructure ENUM technology exist.
• No overall consensus for a particular organizational structure exists.
• Facilitators, vendors and interest group clearly support the open models.
• DGET/OPTA have a neutral position with regard to Infrastructure ENUM and the other stakeholders confirm this position.
• Operators are seen by all stakeholders as initiators/locomotives of an Infrastructure ENUM initiative.
• It is most likely that in the short term the closed models will arise and in the long term these closed models will merge with other models.
• Introduction of Infrastructure ENUM does not require a change in business model except for the email model.

There is only one serious mistake in the thesis: Lennart is assuming that Infrastructure ENUM is only working for VoIP. This is not true. Infrastructure ENUM may also contain PSTN lines, ported and non-ported.

Another minor drawback is the limited reach (only Dutch respondents), but this is recognized in the thesis. It is also recognized that the knowledge of the issues around ENUM and VoIP peering are not the same with all respondents.

Labels: ENUM, VoIP Peering