Yasin Mohammad Reza id: 1354
As From the Name VLR means Visitor Location Register and HLR means
Home Location Register so it has all detail of subscriber so VLR has
temporary details.
Home Location Register (HLR)
The HLR is the reference database for subscriber parameters. Actually
HLR Having all the detail like customer ID, customer number, billing
detail and for prepaid with IN intelligent network its has detail of
current recharge of prepaid user so far its is very complex but i just
make it in simple word for you.
Various identification numbers and addresses are stored, as well as
authentication parameters. This information is entered into the
database by the network provider when a new subscriber is added to the
system. The HLR database contains the master database of all the
subscribers to a GSM PLMN.
The data it contains is remotely accessed by all the MSCs and the VLRs
in the network and, although the network may contain more than one
HLR, there is only one database record per subscriber – each HLR is
therefore handling a portion of the total subscriber database.
The subscriber data may be accessed by either the IMSI or the MSISDN
number. The data can also be accessed by an MSC or a VLR in a
different PLMN, to allow inter-system and inter-country roaming.
The Basic Parameters stored in the HLR are listed below:
Subscriber ID (IMSI and MSISDN)
Current Subscriber VLR (Current Location)
Supplementary Services Subscriber to (Caller Tone, Missed Call Alert,
Any Other Services etc.)
Subscriber Status (Registered or Deregistered)
Authentication Key and AUC Functionality
Mobile Subscriber Roaming Number
Visitor Location Register (VLR)
The VLR contains a copy of most of the data stored at the HLR. It is,
however, temporary data which exists for only as long as the
subscriber is "active" in the particular area covered by the VLR.
The VLR database will therefore contain some duplicate data as well as
more precise data relevant to the subscriber remaining within the VLR
coverage (here coverage means status of customer of last lac location
area code updation )
The VLR provides a local database for the subscribers wherever they
are physically located within a PLMN, this may or may not be the
"home" system. This function eliminates the need for excessive and
time-consuming references to the "home" HLR database.
The additional data stored in the VLR is listed below:
Location Area Identity (LAI).
Temporary Mobile Subscriber Identity (TMSI).
Mobile Station Roaming Number (MSRN).
Mobile status (busy/free/no answer etc.).
Location Area Identity
Cells within the Public Land Mobile Network (PLMN) are grouped
together into geographical areas. Each area is assigned a Location
Area Identity (LAI), a location area may typically contain 30 cells.
Each VLR controls several LAIs and as a subscriber moves from one LAI
to another, the LAI is updated in the VLR. As the subscriber moves
from one VLR to another, the VLR address is updated at the HLR.
As From the Name VLR means Visitor Location Register and HLR means
Home Location Register so it has all detail of subscriber so VLR has
temporary details.
Home Location Register (HLR)
The HLR is the reference database for subscriber parameters. Actually
HLR Having all the detail like customer ID, customer number, billing
detail and for prepaid with IN intelligent network its has detail of
current recharge of prepaid user so far its is very complex but i just
make it in simple word for you.
Various identification numbers and addresses are stored, as well as
authentication parameters. This information is entered into the
database by the network provider when a new subscriber is added to the
system. The HLR database contains the master database of all the
subscribers to a GSM PLMN.
The data it contains is remotely accessed by all the MSCs and the VLRs
in the network and, although the network may contain more than one
HLR, there is only one database record per subscriber – each HLR is
therefore handling a portion of the total subscriber database.
The subscriber data may be accessed by either the IMSI or the MSISDN
number. The data can also be accessed by an MSC or a VLR in a
different PLMN, to allow inter-system and inter-country roaming.
The Basic Parameters stored in the HLR are listed below:
Subscriber ID (IMSI and MSISDN)
Current Subscriber VLR (Current Location)
Supplementary Services Subscriber to (Caller Tone, Missed Call Alert,
Any Other Services etc.)
Subscriber Status (Registered or Deregistered)
Authentication Key and AUC Functionality
Mobile Subscriber Roaming Number
Visitor Location Register (VLR)
The VLR contains a copy of most of the data stored at the HLR. It is,
however, temporary data which exists for only as long as the
subscriber is "active" in the particular area covered by the VLR.
The VLR database will therefore contain some duplicate data as well as
more precise data relevant to the subscriber remaining within the VLR
coverage (here coverage means status of customer of last lac location
area code updation )
The VLR provides a local database for the subscribers wherever they
are physically located within a PLMN, this may or may not be the
"home" system. This function eliminates the need for excessive and
time-consuming references to the "home" HLR database.
The additional data stored in the VLR is listed below:
Location Area Identity (LAI).
Temporary Mobile Subscriber Identity (TMSI).
Mobile Station Roaming Number (MSRN).
Mobile status (busy/free/no answer etc.).
Location Area Identity
Cells within the Public Land Mobile Network (PLMN) are grouped
together into geographical areas. Each area is assigned a Location
Area Identity (LAI), a location area may typically contain 30 cells.
Each VLR controls several LAIs and as a subscriber moves from one LAI
to another, the LAI is updated in the VLR. As the subscriber moves
from one VLR to another, the VLR address is updated at the HLR.