[asterisk-users] single registration per user

[Olle E. Johansson]

18 sep 2011 kl. 22:23 skrev Catalin S.:

> Hello Eric,
>  
> Is about outgoing calls from multiple devices with the same username at aprox same time. The overwritten is for incomming calls. I want to prevent using the same account in multiple devices at same time. The solution with IP will not apply because users may be behind nat or will change everytime multiple access points. Do you have any other clues?

There is no real good way to prevent this. How can Asterisk now which registration that is the valid one? If a device reboots and gets a new IP from DHCP, we do not want to prevent that new registration to prevent the old one from another IP, but the very same device. There's no device ID used in the registration, only the SIP account. 

This also applies to OpenSER/kamailio/OpenSIPS. We can prevent multiple simultaneous registrations in those, but that will also mean that phones that reboot will be blocked until all registrations expire in the server.

/O

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