An MTP/PTP extension may enable MTP/PTP devices to determine which protocol and/or which protocol version to utilize for impending communication. For example protocol and/or protocol version may be requested with a MTP/PTP SetDeviceClass operation that may comprise DeviceClass and/or RequestedVersion parameters. A response to the request may specify a protocol and/or protocol version for impending communication. Moreover, a response may comprise a DeviceInfo dataset comprising one or more fields indicating the protocol and/or protocol version. In various embodiments of the invention, a protocol and/or protocol version may be determined based on a GetDeviceInfo operation. Determination of which protocol and/or which protocol version to utilize for communication between MTP/PTP enabled devices may occur during initiation of communication.