1. A method, comprising: converting header names into a canonical form comprising a plurality of canonical keys, wherein each canonical key represents at least one equivalent header name, and wherein each canonical key has a string and an integer value; providing a mapping between the header names and the canonical keys; and searching for a header name using the canonical key by sequential search using integer comparison.
7. The method as claimed in claim 1 , further comprising updating the mapping of canonical keys to include new representations of existing predefined header names.