We use a Sierra Wireless 555 aircard inside a device we build for wireless transactions. We discovered that in a 11 day period someone was able to send over 498MB of data over this card. The problem is that this was a development unit and was turned off or out of the ubit when some of the transfers took place. The logs on the SA card software show no connections or data transfers but I did get a bill for 3K from the cell carrier.

!XRTT is the latest and greatest digital "secure" network so needless to say we are concerned about the possibility of a security hole somewhere in the system.

Has anyone got any ideas how this could have occurred? We have been racking our brains trying to understand it without success. BTW the cell carrier refuses to provide us written details of the transfers.