There is provided a method and system for communicating data items about a communication network. An original data item for communicating to a destination device is cached to a network data store in association with unique ID (UID) generated to identify the original data item. The UID is then sent as a proxy for the original data item to the destination device. The original data item may be processed (e.g. in response to a type of the destination device) to create a processed data item and the processed data item sent in place of the original data item. The processed data item may also be cached in association with the UID, for example, for reuse to eliminate duplicate processing. The destination device is adapted to return the UID when further communicating the original data item thereby to reduce communication of the original data item about the communication network.