An apparatus, a carrier medium storing instructions to implement a method,
and a method in a node of a wireless network able to receive packets that
exactly or substantially conform to a wireless network standard according
to which each packet includes a header having bits that have respective
correct values in the case that the packet exactly conforms to the
standard. The method includes receiving a start-of-packet (SOP) trigger
that indicates that a packet may have been received, checking one or more
bits in the header to determine whether or not they have their respective
correct values, and continuing to process the packet in the case that the
checking indicates that the checked bits have their respective correct
values. In one implementation, the header includes a first field
modulated at a known rate that has one or more reserved bit locations,
and a second field modulated at a data rate indicated in the first field.
In such an implementation, the checking includes processing the first
field and checking one or more bits in the first field to determine
whether or not they have their respective correct values, and, if the
checked bits of the first field have their respective correct values,
checking the second field for integrity.