How to hide the customer number for the courier?

Question

Telephony

Prompt what thread ready system of a telephony.
What is the task.
Couriers know the numbers of customers, and then they deliver inconvenience to them.
It is necessary to somehow organize a call to the client so that the courier does not know the real phone number.
preferably something from virtual telephony

Answer 1

Solve it administratively. Although the courier for any has a place of delivery and full name, so if it is completely inadequate, it can break through the number

Answer 2

So if the courier knows the full name and address, then he can break through the number
as well, some onlinesim.ru
Through it you can buy numbers

Answer 3

You can proxy calls to customers and back through your telephony, as Yandex does for example - when you want to call a taxi driver, the phone number with a pre-entered extension number is copied to your dialer.
If you didn’t know, then on the phone using commas and; you can set pauses when dialing a number.
I'm not sure if there are ready-made solutions for this, but it seems to me that it is not very difficult to integrate telephony with IS according to this principle.