I can’t help you specifically since I know nothing about Switchvox. My solution to the portability problem was to assign each person a “virtual” number. When this number is dialled, a database lookup determines which “real” phones to dial. When someone changes location, s/he re-assigns the real phone numbers that correspond to her virtual one.
I will translate your message for those who don’t:
[i]
I want to implement an Asterisk solution for a large company with remote sites.
The goal is to allow each worker to keep the same phone number when he changes office and/or moves to another site.
The architecture is based on IPBX (Switchvox DIGIUM) at each site and an Asterisk server.
Who can help me configure Asterisk to create number portability (taking into account that the remote sites are on different networks)?
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