RE: [manet] Request for clarifications on 802.11 4-way handshake

Kostas,

PLCP is added to any 802.11 MAC frame transmitted, yes including RTS, CTS and ACK control frames. And CTS and ACK frames transmission starts right after SIFS, even when it is middle of a slot.

Best Regards

Osama Farrag

-----Original Message-----
From: manet-bounces at ietf.org [mailto:manet-bounces at ietf.org] On Behalf Of Kostas Voulgaris
Sent: Monday, August 22, 2005 6:32 PM
To: manet at ietf.org
Subject: [manet] Request for clarifications on 802.11 4-way handshake

Dear all,

Reading the standards on 802.11 I have a few of questions regarding the 4-way handshake and the PHY operation.

More specifically, it seems that a PLCP header and Preamble is added to the MPDU at the beginning of any data transmission.

If this is correct, does the same rule apply for RTS / CTS and ACK packets? i.e. are a Preamble and PLCP Header added any time one of the aforementioned packets is to be transmitted?

Also, does the transmission of any control packet starts at the beginning of a slot?

As an example, a slot duration according to the standards for DSS system is 20us. A SIFS duration is 10us.

Omitting PLCP Header and Preamble, an RTS packet duration is 160us (1Mbps transmission), occupying 8 slots.

When should CTS transmission begin? Right after the SIFS (i.e. at the middle of the slot), or wait for the beginning of the next slot?

Your prompt reply is highly appreciated.

Best regards,

Kostas Voulgaris