If you want to learn more about our VTA Service, we first advice you to consult our VTA FAQ section as well as our Overview VTA document which gives you a good summary of the service.
The main documents related to the Subscriber Access Line service are:
You can also find useful information under the Swisscom website.
If you are interested in the VTA functionality offered by TELDAS, you should sign one of the following user contracts, but first we recommend you to consult our FAQ "How to become a User":
Technical Documentation (only accessible for Teldas users)
User guides (only accessible for Teldas users)