14.9.3.3. Configure Skype for Business Server 2015 
To complete the Direct SIP configuration with OpenScape 4000, perform
the following steps:
- Add OpenScape 4000 vSTMI (vHG3500) as a gateway to the Skype for Business Server 2015 topology.
- Define dial plan by configuring normalization rules.
- Create a voice policy.
- Define a trunk configuration.
- Assign the voice policy that you created to Skype for Business users.
INFO:
On OpenScape4000V8 DIRECT STP can be configured on vSTMI or STMIX/STMIY.