# Prerequisites

## System requirements <a href="#id-2.1_system_requirements" id="id-2.1_system_requirements"></a>

AddressBase Premium is an addressing gazetteer offering full property life cycle information that can be used within GIS and database systems. For details of Ordnance Survey’s licensed partners, who can incorporate the AddressBase products into their systems, please [see the systems/software page on the Ordnance Survey website](https://www.ordnancesurvey.co.uk/business-government/tools-support/gis/software).

Ordnance Survey does not recommend specific suppliers or software products as the most appropriate system will depend on many factors, for example, the amount of data being taken, resources available within the organisation, the existing and planned information technology infrastructure, and the applications that AddressBase products can be used for.

However, as a minimum, the following elements will be required in any system:

* A means of reading the data, either in its native format, or by translating it into a file format or for storage in a database.
* A means of storing and distributing the data, perhaps in a database or through a web-based service.
* A way of visualising and querying the data, typically a GIS.

## Backup provision of the products <a href="#id-2.2_backup_provision_of_the_products" id="id-2.2_backup_provision_of_the_products"></a>

You are advised to copy the supplied data to a backup medium.

### Typical data volumes <a href="#id-2.3_typical_data_volumes" id="id-2.3_typical_data_volumes"></a>

For reading purposes, it is recommended to store the data on a single hard disc. This will speed up the ability of your computer to read the data.

The table below lists the unzipped file sizes for the GB full supply of the two products.

| Product name                | CSV   | GML    | GPKG   |
| --------------------------- | ----- | ------ | ------ |
| AddressBase Premium         | 40 Gb | 186 Gb | 28 Gb  |
| AddressBase Premium Islands | 1 Gb  | 4 Gb   | 0.8 Gb |


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