Components of OSS

The “Authentication” process

As soon as you switch on your mobile phone after inserting the SIM card, a series of handshaking signals are exchanged between the mobile phone and the Mobile network. The handshaking mainly involves Authentication of the User, Identifying the services user is entitled to and Registering the user on the network. 

The SIM card issued by the mobile service provider is the main source for completing Authentication.  Each SIM card is associated with a unique number called IMSI. The IMSI is in turn mapped to the Mobile number.  There are two more important components which help in keeping you gelled to the network. It’s the HLR (Home Location Register) and VLR (Visitor Location Register).

HLR(Home Location Register)

 In simple words, it’s a repository containing all the details of a mobile user necessary to facilitate mobile services to him/her. It holds information like IMSI, Mobile number, Services subscribed, Services barred etc. The MSC pings the HLR periodically to complete the authentication process.

Addition of new subscribers, changes in the services of the existing subscribers etc are handled by the customer support personnel or the sales people or both. They do this through a Interface termed as CRM (Customer Relationship Management). The changes in the customer profile/services are sent to HLD directly via an API or through the Billing system.  To get the changes done to the subscriber profile from the Billing System, the HLR is also talking to Billing System directly, or using a surround Application or through a API.

VLR(Visitor Location Register) 

This is a subset of the HLR and it comes into picture for Roaming Subscribers.  It’s a shorter copy of the HLR maintained by the Roaming Service providing operator locally to keep the customer hooked to the mobile network and facilitate with the services he/she is entitled to.