Abstract: A signature system with a mechanism to identify element(s) of a signed document includes a sender having a signature module with a digest generator. The digest generator generates digests for identifying selected elements of the document. The resulting “identifying” digests are then used in generating a signature in which the sender signs the digests rather than the original elements. The receiver can then process the signature and use these digests to distinguish between elements, as needed.

Abstract: In a computerized system, a sending computer system and recipient computer system exchange an interchange format message in a resource-efficient manner. For example, a transformation writer at the sending computer system selects and transforms only one or few of a plurality of units of the message at the time. The transformed message units are then streamed to the recipient computer system in accordance with a relevant transformation standard, such as the canonicalization standard in the case of XML messages. A transformation reader at the recipient computer system transforms the messages using a buffer big enough for received message units, and passes the transformed units to a file. Thus, the transformation writer acts as a stream writer to pass a message, and the transformation reader acts as a stream reader at the recipient computer system.