I/WE CLAIM:
1. An apparatus comprising one or more processors including circuitry
configured to cause a first wireless station to:
generate a grant frame including a duration field and a dynamic allocation information field, the dynamic allocation information field including an allocation duration subfield, the allocation duration subfield being set to a value within a predefined range of values, when the grant frame is to grant to a second wireless station a period after a Transmit Opportunity (TxOP), the allocation duration subfield being set to a predefined value which is not within the predefined range of values, when the grant frame is to grant to the second wireless station a period within the TxOP; and
transmit the grant frame during the TxOP.
2. The apparatus of claim 1 configured to cause the first wireless station to
operate as a holder of the TxOP, the grant frame including the allocation duration
subfield set to the predefined value to indicate that a remainder of the TxOP is to
be relinquished from the TxOP holder to a TxOP responder.
3. The apparatus of claim 2 configured to cause the first wireless station to
set a value of the duration field to a result of subtracting from a time remaining in
the TxOP a transmit time of the grant frame and a Short Inter Frame Space (SIFS)
time.
4. The apparatus of claim 1 configured to cause the first wireless station to
set the allocation duration subfield to the value within the predefined range of
values to indicate said first wireless station is to attempt to initiate access to
communicate with the second wireless station at a time which is based on a sum
of the value of the allocation duration subfield and a value of the duration field.
5. The apparatus of claim 1 to cause the first wireless station to transmit the
grant frame in a Contention Based Access period (CBAP).

6. The apparatus of claim 1, wherein the predefined value is 32768.
7. The apparatus of claim 1, wherein the range of values includes the range
of 0 to 32767.
8. The apparatus of claim 1, wherein the first wireless station is a Direct
Multi Gigabit (DMG) station (STA).
9. The apparatus of claim 1 including one or more antennas, and a memory.
10. An apparatus comprising one or more processors including circuitry
configured to cause a first wireless station to:
process a reception of a grant frame from a second wireless station, the grant frame grant frame including a duration field and a dynamic allocation information field, the dynamic allocation information field including an allocation duration subfield, the allocation duration subfield being set to a value within a predefined range of values, when the grant frame is to grant a period after a Transmit Opportunity (TxOP), the allocation duration subfield being set to a predefined value which is not within the predefined range of values, when the grant frame is to grant a period within the TxOP; and
based on the allocation duration subfield, to process a communication in the period after the TxOP or in the period within the TxOP.
11. The apparatus of claim 10 configured to cause the first wireless station to
operate as a responder of the TxOP, the grant frame including the allocation
duration subfield set to the predefined value to indicate that a remainder of the
TxOP is to be relinquished from a TxOP holder to the TxOP responder.
12. The apparatus of claim 11, wherein a value of the duration field is a
result of subtracting from a time remaining in the TxOP a transmit time of the
grant frame and a Short Inter Frame Space (SIFS) time.
13. The apparatus of claim 10, wherein allocation duration subfield is set to
the value within the predefined range of values to indicate said second wireless

station is to attempt to initiate access to communicate with the first wireless station at a time which is based on a sum of the value of the allocation duration subfield and a value of the duration field.
14. The apparatus of claim 10 to cause the first wireless station to process
reception of the grant frame in a Contention Based Access period (CBAP).
15. The apparatus of claim 10, wherein the predefined value is 32768.
16. The apparatus of claim 10, wherein the range of values includes the range
of 0 to 32767.
17. The apparatus of claim 10, wherein the first wireless station is a Direct
Multi Gigabit (DMG) station (STA).
18. The apparatus of claim 10 including one or more antennas, and a
memory.
19. A product including one or more tangible computer-readable non-
transitory storage media comprising computer-executable instructions operable to,
when executed by at least one computer processor, enable the at least one
computer processor to implement a method at a first wireless station, the method
comprising:
generating a grant frame including a duration field and a dynamic allocation information field, the dynamic allocation information field including an allocation duration subfield set to a predefined value, the duration field being set to a result of subtracting from a time remaining in a Service Period (SP) a transmit time of the grant frame and a Short Inter Frame Space time; and
transmitting the grant frame during the SP.
20. The product of claim 19, wherein the method comprises operating the
first wireless station as source station of the SP, and relinquishing a remainder of
the SP from the source station to a destination station of the SP.

21. The product of claim 19, wherein the predefined value is 32768.
22. The product of claim 19, wherein the first wireless station is a Direct
Multi Gigabit (DMG) station (STA).
23. A product including one or more tangible computer-readable non-
transitory storage media comprising computer-executable instructions operable to,
when executed by at least one computer processor, enable the at least one
computer processor to implement a method at a first wireless station, the method
comprising:
processing a reception of a grant frame from a second wireless station, the grant frame including a duration field and a dynamic allocation information field, the dynamic allocation information field including an allocation duration subfield set to a predefined value, the duration field being set to a result of subtracting from a time remaining in a Service Period (SP) a transmit time of the grant frame and a Short Inter Frame Space time; and
performing the role of a source station of the SP for a remainder of the SP.
24. The product of claim 23, wherein the predefined value is 32768.
25. The product of claim 23, wherein the first wireless station is a Direct
Multi Gigabit (DMG) station (STA).