"Number portability can manage telecom explosion"
May 2, 2008

Shamim Khan, VP (international numbering services) of Neustar, is a well-known expert on number portability solutions. In an e-mail interview with Tabrez Khan, she discusses the mechanisms for implementing number portability and its benefits to telecom operators and customers

Can you throw some light on the routing mechanisms for number portability? How efficient are these?

There are 2 methods of implementing number portability. One is a call forwarding method where the call has to be forwarded from the donor network to the recipient network. This method is inefficient in that it has to traverse through multiple networks before the call reaches the ported number.

The second method is through an authoritative Centralized Data Base (CDB) where once the number is ported, the CDB broadcasts the information to all authorized interested parties. The authorized interested parties are primarily operators who use information in the database for call routing purposes, law enforcement agencies, and service bureaus.

What kind of software modifications are required to enable number portability?

For a successful implementation, a core CDB system based on a proven and existing CDB should be deployed by a neutral third party, with appropriate modifications and customizations in order to conform to India's numbering plan and portability business rules. From an operator perspective, query databases and their respective management systems (which interface with the CDB) will need to be deployed.

Additionally, the operators' downstream Operational Support Systems (OSSs) will need to be modified to support both incoming telephone numbers that appear to belong to a foreign network, as well as outgoing telephone numbers that will be supported by other networks once ported. To satisfy the number portability needs of a country with the size, growth, and complexity of India, it will be very important to start with a stable system that has been proven in large markets like India.

What about the cost to operators and subscribers?

Each market is different in terms of costs that are absorbed by the operators and the subscribers. Operators often collectively pay for the CDB, its operations, and the system enhancements needed on the operator networks themselves. Optionally, some of these costs are passed on to consumers in the form of a token porting charge or a minimal universal service tax. This is really dependent on the competitive dynamics of that market as portability becomes a customer acquisition tool.

Do you think the concept will succeed in the Indian market, given the fact that operators may have to shoulder a cost burden?

The Indian mobile market is very competitive and dynamic with double digit growth. Once deployed for portability purposes, a CDB has many applications. One example of this is using the CDB for number management. Given India's growth, it's quite possible the total phone numbers in its current numbering plan may run out, requiring changes to the number plan.

The deployment of a numbering plan change would require costly changes to the operators' networks and OSSs. A CDB can be used to allocate the available pool of numbers in a much more efficient manner (on an as needed basis, for instance, rather than in blocks of numbers), thereby avoiding the need to make numbering plan changes.

Another example is the ability to facilitate the routing of multimedia messages (MMS) and text messages (SMS) using fields in the centralized database. Therefore, after shouldering the initial cost burden, the many beneficial applications supported by a CDB can help justify the costs for the operators.

A key requirement in number portability is to maintain databases of ported numbers. How effective is this system with regard to availability, maintenance, operating costs, etc.?

The communications industry in general has very high standards for availability and reliability and a CDB service has to meet those stringent service levels. It's much more efficient to operate a "one to many" connection v/s a "many to many connection", this is the strength of a centralized approach. It assures consistent inter-operability and services and eliminates the need for each operator to build or modify interfaces with multiple operators.

Will it benefit consumers and operators or will it lead to needless competition?

Portability gives consumers choice without losing a precious "identity" which the phone number often represents. For example, in a market like India with very high prepaid subscriber levels, consumers will be able to keep one identity for receiving calls.

Regardless of post-paid or prepaid service, for individual professional services (tutors, consultants, and small family operated businesses), the telephone number is the quickest means to get new business, manage orders, replenish inventory, and reach new customers. Therefore, portability is quite beneficial to small businesses, as they are no longer tied to their operator should a better offer be made available to them, since they can keep their telephone number. For operators, portability can be used as a customer acquisition tool.

Interconnect and roaming settlements are an important part of telecom operations, how can operators be assured of these being addressed in the new billing system?

The traditional interconnect and roaming settlement arrangements are not affected by number portability. The CDB enables the appropriate direct routing of calls to ported numbers and then operators' existing billing and settlement systems continue to do their function without significant impact.

The use of a centralized number portability approach (versus the call forwarding method) actually lessens the burden on these systems, as calls do not need to traverse intermediary networks in order to be completed, thus avoiding any complicated settlement schemes.

Any caveats while implementing number portability that need to be noted?

A couple of points are worth noting:

* The CDB can also be used to facilitate the proper routing of emergency and law enforcement services. Both of these areas require the proper tracking of ported numbers.

* Scale, experience, and stability should be a very important factor in determining the right solution and provider for number portability in India, given its size and complexity.