VLR Vs HLR

[fuzzyrabo]

Why do I need a VLR if every time I initiate a service I go to the HLR?

Thanks In Advance

[uel888]

Review GSM basics, theres a lot of tuts in this forum. Use search buddy :-)

Why do I need a VLR if every time I initiate a service I go to the HLR?

Thanks In Advance

[firstmaxim]

VLR has been introduced to reduce the signaling load on the HLR. So, you do not have to go to the HLR everytime (when you register, activate services, update location, etc). It is analogous to having a branch office that posseses a copy of your profile that exists in your corporate Head Office. You don't have to go to the HO everytime.

[huaweiradio]

There are many reasons for having a HLR and VLR which you can find in GSM Courses but I think one simple example will clear your Question.

For International Roamer which comes in your Network.His Data will be copied in Your VLR (Temporary as he/she in your Network) during LU (Location Update. Without VLR how can he/she make a Call in your Network.

When a terminating call or SMS comes to a Subscriber. The Subsriber Current VLR is only know to HLR which helps to route the Call also. HLR Holds a permenant Subscriber Data and Mobile current Location in the Whole World (VLR Address).

VLR has only the temporary Data of Subsriber.