Patent ID: 8812849

Claim:
A computer-implemented method for controlling an upload of a block of data, the method comprising: receiving a plurality of blocks of data of an email attachment, wherein each block in the plurality of blocks of data is of a predetermined size, the predetermined size based on capabilities of at least one of a client device, a server, or a network; receiving a characterization for a block of data in the plurality of blocks of data; comparing, using a processor during the receiving of the plurality of blocks of data, the characterization for the block of data to a listing of characterizations in an index storing characterizations identifying previously stored blocks of data; and if the characterization for the block of data matches a characterization in the index: canceling the receiving of the block of data, identifying, using the characterization in the index, a previously stored block of data that is identical to the block of data in the plurality of blocks of data, and attaching the previously stored block of data to an email as part of the email attachment.