pls brief about functionality of MNP

Number Portability in simple terms means that Customer as end user shall be able to move 

about in other networks of own service provider or others,  without the necessity of a change 

in his phone number. The intricacy in technology is more about routing the incoming calls to 

the subscriber while he is outside home network. In case of Mobile networks this is already 

happen by enabling national and international roaming. In fact in mobile technology, the 

subscribers are always in roaming condition even while in local network. Hence, it is possible

 to get serviced by different service providers within the local network also by enabling 

"Regional Roaming' feature. At present the subscribers are not given the facility to log in 

to other networks in local area. If this restriction is removed, subscriber can log into to 

other service provider network systems and get serviced which is equal to "Number Portability".

  Charging can done based on revenue sharing principle as in vogue for National and 

Inter national Roaming. However, there is certain intricacies in case of "Incoming  calls". 

Incoming call routing: Currently the call routing is in the Land line network is based on the 

geographical locality of the called subscriber that is determined by the routing digits in the

 numbering plan. At the time introducing Mobile system the Telecom authorities unnecessarily 

made the mobile service, co terminus with the existing telecom circle, and given different 

numbering plan for each area even though the service provider has operation in different 

telecom circles. The right thing to do was to have a service provider based numbering plan 

so that call routing can be done based on service provider identity. I happened to be the 

head of technology in putting through one of the first mobile system in Mumbai in 1995.  

Identifying the need for a service provider based numbering plan I had proposed the 

following which is reproduced here for telecom technology oriented members, if interested. 

Feasibility of proposed numbering plan in Wireless communication networks.  

The service provider will have own Home Location Register (HLR) or a business tie up with 

a centralized HLR provide. The HLR can sit anywhere in the country and have information 

of the identity of the customer’s Visited Location Register. The data of the customers under 

the service provider is entered in this HLR. Instead of the geographic destination code, the 

discrete service provider number is translated as the HLR number for the purpose of 

signaling between HLR and VLR. 

The call originated from various MSC/ VLR / GATEWAY which communicate with the Service Provider’s 

HLR to get the identity of the address of the MSC / VLR for routing the call directly to the terminating 

switch where the customer is roaming at that time by optimal routing.  

The Call Data records related to the call and usage of various network and systems are transmitted 

to the common billing system for accounting and appropriation of revenue share. 

The proposed numbering plan can be implemented straightaway in the GSM & CDMA Networks with 

some changes in the switching software architecture. This numbering plan can take care of 1 billion 

subscribers for each Service Provider. 

Number portability in Mobile networks can be readily achieved with this method. 

Although the Customer belongs to a Service Provider, he will have freedom to choose and use any 

network and any carrier for inter-network for availing service. 

Optimal Routing is envisaged to optimize direct routing of calls to the destination network. 

Proposed below is the Service Provider based International Multi-media communication 'Numbering Plan'. 

Format of the proposed International Multi-media Called Number which is also the Customer Number (Cn) will be:-

Cn = + Cc Sp Ts Sn (15 digits and according E164/E165).

Scope of numbering plan:

a)  1 billion to 10 billion NUMBER per Service Provider. 

b)  The Area Code is replaced by Service Provider identity. Numbering can accommodate 1000 Service Providers. 

c)  Exclusive Customer number over the entire numbering and exclusive Subscriber number under each  

Type of service.

d)  Service Provider identity become discrete digit stream for identify and rout the signaling and call content to 

appropriate network, switching system and terminal device. 

e) The Customer number (Cn) will be same for various services; Voice, Fax, Data, Video and Multimedia 

services.  

A discrete digit (Ts) in the numbering plan identifies and routes the call to required type of transport media, 

network, switching system and terminal device.

Components of proposed numbering plan.

‘+’ is the Inter-National Access code: (translated to local needs of the country of origin.) 

Cc = Country Code (91 for India)                                    

Sp = Service Provider identity (000 to 999) 

Ts = Type of Service (1 to 9) (1=Voice, 2=FAX, 3=Data, 4=Video, 5-9 reserved) 

Sn = Subscriber Number (PQ MCDU. 9 /10 digits) (0000000001 to 9999999999)

In the example below, 9 digits Sn is used. 

For National access (Voice call) Called number Cn = Sp Ts Sn = 210 1 876543210 

International number: (Voice Call) Cn= + Cc Sp Ts Sn = + 91 210 1 876543210 

For the time being a 9 digit Subscriber would be enough for the telecom 

Numbering in India to keep the total digits within 15 digits. 

In due course, a distinctive International Service provider code can be derived combining the Country 

code Cc with Service provider code into one Sp code. Example: Cn = Sp Ts Sn, where Sp can be a 5 to 6 

digits International Service provider code.  With that Sn can be expanded to 10 digits.   

Carrier Selection.  Preferred carrier Code:  Pc. 

A distinct code (Pc) proposed for Preferred Carrier Selection.  

This code will not be part of the numbering scheme. 

Pc is keyed in during the call set up when asked for it by the switching system during the progress of call, 

using interactive intelligent networking.  Pc, a two digit or three digit predefined code made available to the

caller to request the network to route call according to his choice. The system translates the code to a 

routing code at every switching point to route the call accordingly. 

In due course there can be discrete number for every service provider across the world so that the 

Country code Cc also could become part of Sp to make the Called Number (Cn) point to the 

Service Provider instead of a geographical location anywhere in the world. 

For example, there can be 1000 discrete service provider identity using the country code 91 as the 

prefix ranging 91000-91999. 

A ten digit Subscriber number will provide 10 billion numbers. 

Then the range of the Called Number (Customer Number) Cn will be = Sp Ts Sn

 = 91000 0 0000000000 to 91999 9 9999999999. This numbering plan will provide 1000 sets of 10 Billion 

numbers for each service type.

Implementation of the proposed numbering plan in Wired Networks for easy implementation of number 

portability. 

To realize implementation the proposed numbering plan and number portability based on it in 

Wired networks, it is necessary to introduce Roaming feature and facilities in Wired network also as 

an easy way to enable Number Portability.  ‘Roaming’ feature can be introduced in Wired Networks.    

The end user terminals: Discrimination between Fixed line phones and Mobile phones also will vanish 

as fixed phones could have SIM and related features needed for logging into the network as in the 

case of GSM phones. With the advent of very high bit rate data transactions, the discrimination 

between Wired and Wireless networks will vanish. This is because as the bit rate increases, the cell area

 becomes smaller and smaller making the wireless portion in the network less and less.  In effect, 

the topology of Fixed Line and Mobile networks becomes same. Therefore, it would be possible to 

have uniform type of switching systems, network and numbering plan for both Wired and Wireless 

communication facility.  

The Fixed line network operators can provide roaming feature in the fixed networks by using Network 

switching systems with VLR integrated in it to look into common HLR where the subscriber data reside, 

to get information about the customer and his current location. 

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Abraham Paul. Ex-VP Technical Sales Siemens SPCNL, India / GM & SMT TBG,

BPL Mobile/ TES(I) DoT India)e-mail: papaul@hotmail.com 

Sonal is the master in this field...

Mobile number portability (MNP) enables mobile telephone users to retain their mobile telephone numbers when changing from one mobile network operator  to another..