Can 2 different useragents/devices with different IPs log into the same subaccount without issue?

General
1

If a person has two devices, such as a tablet and a laptop, and wants both to be logged into a subaccount, and both have different IP addresses, is this possible or will this cause problems?

If it causes problems, why? Also, if so, what is the workaround, if any?

2

In theory, yes, two registrations on different devices with the same subaccount is possible. This is called SIP-forking. VoIP.ms does support it.

However, there are drawbacks of doing that:

  • Since both devices have the same login, you cannot transfer or forward calls between them.
  • There are sometimes quirks with the registration and call routing that make one device receive a call (ring) but not the other.
  • It is harder to diagnose a registration or call routing issue because both devices will appear as one.
  • If both devices are at different locations, only one address may be configured for e911. One of them will show an incorrect address when 911 is called.
  • If you answer a call on one of your devices, the other might continue to ring for several seconds due to signaling delays. This is called “ghost ring”.
  • In the audit or CDR, you will not be able to distinguish which device made or picked up a call, only the subaccount name will show.

My suggestion: use two distinct subaccounts. If you want them to ring simultaneously during an incoming call, use a Ring Group. Two subaccounts may also share a voicemail if necessary.

Using SIP-forking is a way to circumvent the restrictive licencing of some PBX that charge per subaccount. Since VoIP.ms does not charge extra for subaccounts, there are no real reason to use it.

1 Like
3

Hello @sipper,

In all practicality, the servers at voip.ms will not know to which device to send the incoming calls because both devices will fight for the registration, so you should have one subaccount per device, or no two devices at the same time connected to the same sub account.

Kind regards!

1 Like
4

I agree, use sub accounts with a Ring Group for the DID, but make sure they use the same server IP/Address.

1 Like
5

I have two devices that log into the same sub account but I ensure that only one at a time does so.

I don’t think either has ever spent any time near the 911 address as both are mobile devices.

6

Hi @Rbphilip,

If only one device uses the subaccount at any given time, that should not create any routing problem. But creating a subaccount is so easy, why not create two subaccounts anyway and not risk having SIP-forking issues at all if you mistakenly connect both devices at the same time?