Subject: Mobile Computing

Difficulty: Medium

Marks: 4 Marks

Home Location Register (HLR):

• It is a database for managing the mobile subscriber.
• HLR stores permanent data of subscriber which include subscribers service profile, location information and its activity.
• A home subscriber charges are less then the roaming subscriber.

Visitor Location Register (VLR):

• It is a database which consists of temporary information about subscribers which is used by MSC in order to provide services to visiting subscriber.
• MSC updates the VLRby determining which users are in roaming.
• Once, the roaming mobile information is updated, then MSC sends necessary information to roaming mobile subscribers so that roaming mobile call can be properly routed.