LA (Location area)

Location Area (LA) is a concept in cellular network technology that helps in managing the mobility of mobile devices. In a cellular network, a mobile device communicates with a base station, also known as a cell site, to access network services. As the mobile device moves, it may switch its connection from one cell site to another. Location areas are defined to group cells together in a logical area, which simplifies the management of mobile devices that move between cells.

In this article, we will discuss what is a location area, how it works, and its importance in cellular network technology.

What is a Location Area (LA)?

A Location Area is a group of cells in a cellular network that are logically defined to simplify the management of mobile devices that move between cells. A location area consists of one or more cells that are controlled by a single base station controller (BSC) or a radio network controller (RNC) in the network. A location area is identified by a unique location area identity (LAI).

The LAI is composed of three parts:

• Mobile country code (MCC): A three-digit code that identifies the country in which the mobile network is located.
• Mobile network code (MNC): A two or three-digit code that identifies the mobile network operator within the country.
• Location area code (LAC): A two-byte code that identifies the location area within the mobile network.

The LAC is unique within a mobile network and identifies the cells that belong to the location area. A mobile device that is registered on a network is assigned to a location area. When a mobile device moves from one cell to another within the same location area, it does not need to register again with the network. However, when a mobile device moves from one location area to another, it needs to register with the network again.

How Location Areas work

When a mobile device is turned on, it searches for a network and registers with the network. During the registration process, the mobile device provides its identity to the network, which includes the international mobile subscriber identity (IMSI) and the location area identity (LAI).

The network uses the LAI to determine the location of the mobile device. If the mobile device is within the same location area, the network does not need to perform any additional actions. However, if the mobile device moves to a different location area, the network needs to update its location in the network.

When the mobile device moves to a new location area, it sends a location update message to the network. The message contains the mobile device's identity and the new location area identity. The network updates its database with the new location of the mobile device.

The location update message triggers a series of actions in the network. The network updates the routing information for the mobile device, which allows the network to deliver incoming calls and messages to the mobile device. The network also updates the location information for the mobile device in the home location register (HLR) or the visitor location register (VLR), which stores the subscriber's profile and location information.

Importance of Location Areas

Location areas are important in cellular network technology because they simplify the management of mobile devices that move between cells. By grouping cells together in a logical area, location areas reduce the number of location updates that are required when a mobile device moves between cells.

Location areas also help to optimize the use of network resources. When a mobile device moves between cells within the same location area, the network does not need to perform any additional actions. This reduces the signaling traffic on the network and frees up network resources for other mobile devices.

Location areas also help to improve the network's performance. When a mobile device moves between cells within the same location area, the handover process is faster and more reliable because the cells are under the control of the same base station controller (BSC) or radio network controller (RNC). This means that the network can ensure a seamless transition for the mobile device without any disruption in service.

Another benefit of location areas is that they allow the network operator to optimize the network planning and resource allocation. By analyzing the traffic patterns within a location area, the network operator can allocate network resources, such as bandwidth and capacity, more efficiently.

Location areas also provide a level of security for the network. When a mobile device moves from one location area to another, it needs to register with the network again. This ensures that the network can authenticate the mobile device and prevent unauthorized access to the network.

Location areas also play an important role in emergency services. When a mobile device makes an emergency call, the network uses the location area information to determine the location of the mobile device. This allows the emergency services to respond quickly and accurately to the emergency.

Conclusion

Location areas are an important concept in cellular network technology. They provide a logical grouping of cells that simplifies the management of mobile devices that move between cells. Location areas reduce the signaling traffic on the network, optimize the use of network resources, and improve the network's performance. Location areas also provide a level of security for the network and play an important role in emergency services.

As cellular networks continue to evolve, location areas will remain an important concept in managing the mobility of mobile devices. With the increasing demand for mobile data and the emergence of new technologies such as 5G, location areas will continue to play a critical role in ensuring a seamless and reliable mobile experience for users.