Connect to SQL Server through 3g/4g device authenticating by IMEI

Question

I have many mobile devices (PDA's, Tablets...) which connect to a SQL Server. When the device is connected through WiFi, it's easy for the firewall to reject unknown MAC adresses.

But I'm lost when the device is connected through 3g/4g.

Is the IMEI somewhere in the TCP packet so I can read it and filter the access to the SQL Server? If not, can I add it? How?

The software is developed under Visual Basic .NET

Answer 1

No, higher level data doesn't care nor remember what lower level transport is being used. This information is not available.

Don't connect directly to the database, as that has many downsides.

I'd suggest exposing the data through a web service.