can be the case for example when multi protocol station 203 1 is already aware that previously imposed network allocation vector nav protection extends through at least the end of the transmission of the first protocol message for example multi protocol 203 1 itself might have already set the network allocation vector as for the case of ps_poll frame 802 during interval 904 access point 201 responds to the clear_to_send that comprises info address with at least one data frame multi protocol station 203 1 operating in accordance with the second protocol transmits acknowledgement frame 905 in response to the data frame or frames from access point 201 acknowledgement frame 905 in some embodiments comprises a duration field with a value that effectively ends network allocation vector protection interval 903 as part of bluetooth activity interval 906 the first protocol part of multi protocol station 203 1 transmits in some embodiments another first protocol message e g a bluetooth hv3 or u201c high quality voice 3 u201d packet etc on shared communications channel 205 it is to be understood that the above described embodiments are merely illustrative of the present invention and that many variations of the above described embodiments can be devised by those skilled in the art without departing from the scope of the invention for example in this specification numerous specific details are provided in order to provide a thorough description and understanding of the illustrative embodiments of the present invention those skilled in the art will recognize however that the invention can be practiced without.