The Infrastructure Atlas (ISA) as part of the Gigabit Basic Book is a central information and planning tool for broadband expansion in Germany. It provides an overview for the initial planning stages of broadband expansion projects and serves to prepare specific shared use claims in the advanced planning process.

The ISA contains the infrastructure data of several 1,000 network operators and makes this available to authorized companies, but also to the federal government, federal states, districts and municipalities in the context of broadband expansion. The geodata, for example the route of fiber optic cables, is depicted on digital maps in the ISA.

As the owner or operator of a public supply network, for example as an energy supplier or telecommunications company, you must provide data for the ISA and update it regularly. This involves data on all facilities that can be used to set up or expand telecommunications networks. For example:

• Fiber optic lines,
• protective or empty conduits,
• radio masts,
• radio relay lines,
• carrier infrastructures (e.g. traffic lights, street lights),
• access points.

In addition, you must also provide data to the ISA if you are the owner or operator of other physical infrastructures that are suitable for the installation of short-range wireless access points.

In addition to the ISA, the ISA+ represents data that you can provide voluntarily. For example, you can voluntarily provide your data on passive network infrastructures for the ISA+ for the specific preparation of shared use claims and thus reduce the effort involved in responding to requests for shared use, as you can then refer to the infrastructure atlas.