State of knowledge

March 2024
from ProCall Voice Services version 2403.0

Assigning phone numbers to users and end devices

In ProCall Voice Services, internal and external phone numbers are assigned to users and end devices.

Each phone number may only be assigned once.
No special configuration settings on the part of estos are necessary for uniquely assigned telephone numbers.

The setup and use of multiple exchange lines is possible without restriction under the following conditions.

Uniquely assigned phone numbers

The extension range of the exchange lines is not the same.


+49 30 456987 20 – 39
+49 89 321546 70 – 99

The assigned phone numbers are unique.

The extension ranges overlap, but the internal numbering plan is unique so that each internal extension is assigned to exactly one user.

Please note that all phone numbers are still available for assignment in estos UCServer. If a phone number with the same extension is assigned twice, an error will occur.


+49 30 456987 10 = OK
+49 89 321546 10 = error