METHOD AND APPARATUS FOR COMPUTING @$apos;N-BIT AT A TIME@$apos; CRC@$apos;s OF DATA FRAMES OF LENGTHS NOT MULTIPLE OF N

A method for allowing a Cyclic Redundancy Check (CRC) checking 'N-bit at a time' of a data frame having a length not necessarily a multiple of said N-bit, said method comprising the steps of:

• 1. (a) receiving said data frame;
• (i) extracting a length from a protocol header of said data frame;
• (ii) determining a misalignment d between said length from the protocol header of said data frame and said N-bit of said data frame;
• and
• (b) simultaneously receiving N-bit of said data frame;
• (i) determining CRC on said received N-bit;
• (ii) updating a Field Check Sequence (FCS) register;
• (iii) determining if said length of said data frame is known, wherein when said length of said data frame is not yet known, repeating steps (b)(i)-(iii) 'N-bit at a time', and
• when said length of said data frame is known, comparing said extracted length from the protocol header of said data frame to a number of said received N-bit of said data frame and determining whether more bits are to be processed,
• further wherein, when more bits are left to process, repeating steps (b)(i)-(iii) 'N-bit at a time', and
• when no more bits are left to process, comparing a current value of said FCS register to a pre-stored vector corresponding to said misalignment d, wherein when a match occurs checking of said data frame passes and said data frame is accepted, and when a match does not occur checking of said data frame fails and said data frame is rejected.