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Please tell me how to edit the supported rates list on an 802.11g ERP client (not access point). For lab purposes I would like to vary the rates supported. The usual client utility appears not to support this configuration change.

I would think that depends on the vendor's nic cards. I recall that some proxim cards let you set for just 802.11b(you get that rate set only) or 802.11(you get that rate set only). This is what I did with my testing for the CWAP. It is also AP dependant. I was able to, on an ASUS AP, set myself up for just 802.11 only. Plus, I do recall with the ASUS I was able to select a range or full rate set in ERP mode.

You may be able to mess with the client adapter mibs locally to see if you can change them, but that may be limited or restricted by the clinet adapter's firmware and or driver.

The only other option is to get commview 5.0 and with its packet generator "create" the packets with the rate set you want for behavioral testing. The commview driver for the supported wireless nic should overcome any vendor limitation. So when using a card with the commview driver you can create beacons et. al. with the supported rates you wish. Just make the packets valid and pump them out.

Just a thought for I am not sure what you want to accomplish.

Regards...

For lab purposes I would like to take an ERP client, omit rates 1, 2, 5.5, and 11 from its supported rates list, associate it to an ERP access point, and observe what happens later when the ERP access point requires protection. My theory is that without rates 1, 2, 5.5, and 11, the ERP client will not be able to transmit protection frames and so will ignore the requirement.

I have never heard of a client utility that offers to edit the client's supported rates list. I only hope someone has. Thanks.

I understand, you want to see if the supported rates act as a discriniator or switch to see if proteciton frames are sent from the client.(CTS self?) Also, wouldn't the lack of precense of barker, cck or pbcc act as a discrimiator? I mean if the ERP station sends out its packets in erp-ofdm anyways the AP knows and the erp client knows its an ERP guy so when a non erp guy comes into play its protection is enabled regrdless of the supported rates. Its protection switch is signalled from the ap or the precense of non erp modulation. Vendor specific??

Maybe what I am trying to say is just the fact it is an erp client by modulaitoin automatically makes it support protection regardless of the rates and or signaling to switch to proection mechanisim.

What I recall is that the rates act as a discrminator for associating. Not sure for protection. Let us know how it goes Dexter.

There are several situations wherein an ERP access point will set its Use_Protection=1 in its beacons. Upon receiving those beacons each ERP client of that BSS is required to start using protection mechanisms. Protection mechanisms involve transmitting frames at nonERP rates to provide virtual carrier detection cover for other frames transmitted at ERP-OFDM rates.

If an ERP client has disabled its nonERP rates what will it do when it receives the signal to start using protection? I fear I will not find a client utility that will allow me to edit a client's supported rates list and demonstrate the result.

ERP access points do allow their supported rates lists to be edited. So far all reports are that protection is never used by an ERP access point once its nonERP rates are disabled. Observers disagree over the reason. Has protection become unneeded or has protection become impossible? And who is Dexter? Thanks.

Dexter as in Dexter's Lab:)

Criss how did you make out with your testing

Hi JS: Thanks for asking. Posting on this and other venues has turned up no method of configuring a client's supported rates list. /criss

Criss_Hyde Escribió:

Hi JS: Thanks for asking. Posting on this and other venues has turned up no method of configuring a client's supported rates list. /criss

criss, acutally something just occured to me. Have you considered an SDR???

http://www.sdrforum.org/

http://www.gnu.org/software/gnuradio/

http://www.flex-radio.com/


I believe you can run one on a linux box and set whatever rates you wish. Something to look into...


Regards..

Hi JS: I followed your URLs and studied up on the topic. I looks like this tech is too raw as yet for me. Thanks. /criss