A system comprising a switching entity disposed between healthcare data processing resources and non-healthcare data processing resources. The switching entity is capable of operation in a first state in which an end user device is communicatively coupled to the healthcare data processing resources to support a healthcare session and a second state in which the end user device is communicatively coupled to the non-healthcare data processing resources to support a non-healthcare session. If the authentication request message is received while the switching entity is operating in the second state and a particular non-healthcare session is in progress, and the selected authentication entity is the healthcare authentication entity, initiating a memory purge at the end user device. Attacks on the healthcare data processing resources, both from the non-healthcare resources directly and via the end user device, are thus prevented.