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I'm curious if anyone can think of a reason a BlockAck would be sent not in response to a BlockAckReq. This changes the way the duration ID is calculated (according to the standard) but just seems...well...crazy. :?


Thoughts?

...adding to this. If BlockAcks can be sent not in response to a BlockAckReq...where are they sent to? (What is the RA field address?)

I am guessing this is similar to CTS frames not in response to RTS frames, but I just don't see it in the standard or on the web.

Is this in an 802.11e or 802.11n environment? There are some improvements in 802.11n (Draft) that remove some of the overhead using BlockACK frames in 802.11e.

Hey Bryan-

Neither specifically. I just noticed in the 802.11-2007 standard (the big kahuna standard) that it mentioned a BlockAck duration ID would be equal to or greater than the amount of time needed for SIFS+Ack if the BlockAck was not in response to a BlockAckReq. Seemed rather strange. I'll try checking the other draft standards etc and see if I can find anything.

Thanks.

If I understand this correctly, the BlockACK is used to make the network faster. A STA can send one ACK that covers several frames that were received of diferent types, voice, video, data, and could be sent with or without a request. I will try to do some homework and post a more complete answer if I find one shortly.

...Ok I have an idea for this, but my diagram is cutting squished when trying to post it. I'll see if I can explain it later. ;-)