Explain the relevance of canonical XML to digital signatures. What contextual information can be included in the canonical form? Give an example of a breach of security where the context is omitted...

Explain the relevance of canonical XML to digital signatures. What contextual information can be included in the canonical form? Give an example of a breach of security where the context is omitted from the canonical form. A coordination protocol could be carried out in order to coordinate the actions of web services. Outline an architecture for (i) a centralized and (ii) a distributed coordination protocol. In each case, describe the interactions needed to establish coordination between a pair of web services. Compare RPC call semantics with the semantics of WS-ReliableMessaging: i) State the entities to which each refers. ii) Compare the differing meanings of the available semantics (for example, atleast-once, at-most-once, exactly-once).