AS8387 T-SYSTEMS-AT Rennweg 97-99

T-SYSTEMS-AT is the Austrian network of Deutsche Telekom's corporate IT arm,

registered today as Deutsche Telekom Global Business Solutions GmbH and long

known as T-Systems Austria. The registry name is one of those that reads as a

street address, Rennweg 97-99, which is simply the Vienna office.

What it's used for

• Managed ICT services for corporate and public-sector customers in Austria: hosting, managed WAN and remote-access services, and the systems T-Systems runs on their behalf. Reverse DNS across the space is full of t-systems.at service names, including management and dial-in infrastructure.
• Service infrastructure for the Deutsche Telekom group in Austria. Parts of the space resolve to t-mobile.at and to the s-budget-mobile.at MVNO, so the AS also carries operator-side systems rather than only customer workloads.

Notable

• This is a B2B and internal-services network, not an eyeball one. Magenta's Austrian consumer broadband and mobile subscribers live on other ASNs; the kind here follows what the AS actually carries, not the Telekom brand on the door.
• About 90,000 IPv4 addresses across a small number of prefixes, including a full legacy 164.3.0.0/16, which is a sign of an old allocation to the T-Systems predecessor rather than a modern assignment.

Interesting

• The handle preserves a company that no longer exists under that name. Deutsche Telekom retired the T-Systems brand for much of this business and rebranded it Global Business Solutions, but the AS handle and the reverse DNS both still say T-Systems, which is the usual way corporate renamings show up in routing data.