DSSS and OFDM
Last Post: March 10, 2008:
-
I want to make you a question about AP working with DSSS and OFDM.
As I know, almost all the AP 802.11g are compatible with 802.11b, my question is, if I have an AP working in mixed mode (802.11b/g) and one b client connect to my AP, all the other g clients change to mode b?
I mean, one b client change the operational mode of the AP and restrict the bandwith to 11Mbps instead of 54Mbps?
Thanks! -
All g devices switch to protected mode when a b device connects.
All devices are capped at 11Mbps, and no g-speeds are allowed.
This will scatter to the surrounding APs too.
If you must have g devices, and you need to protect their speed, set up another network, set to g-only. -
I want to make you a question about AP working with DSSS and OFDM. As I know, almost all the AP 802.11g are compatible with 802.11b, my question is, if I have an AP working in mixed mode (802.11b/g) and one b client connect to my AP, all the other g clients change to mode b?
Nope... B client enters the BSS and then the "protection mechanism" kicks in.
Download and read this whitepaper. Required reading if you ever plan on taking the CWNA and/or CWSP exam.
http://cwnp.com/learning_center/search_details.php?doc_id=l7w2 -
Aetherer> "All devices are capped at 11Mbps, and no g-speeds are allowed."
Is this correct? I thought it's only the protection mechanism, and other things like b STA seizing the medium for oh-god-so-long, that degrades mixed mode throughput.. -
Aetherer> "All devices are capped at 11Mbps, and no g-speeds are allowed."
Is this correct? I thought it's only the protection mechanism, and other things like b STA seizing the medium for oh-god-so-long, that degrades mixed mode throughput..
That is not correct. ERP-OFDM radio cards continue to use ODFM data rates. The protection of using CTS_to_Self frames slows things down due to extra overhead. The white paper I referenced earlier explains in detail. -
It's nice to have things clarified.
Thanks Mr MP. -
Mister Multipath Escribi?3:
I want to make you a question about AP working with DSSS and OFDM. As I know, almost all the AP 802.11g are compatible with 802.11b, my question is, if I have an AP working in mixed mode (802.11b/g) and one b client connect to my AP, all the other g clients change to mode b?
Nope... B client enters the BSS and then the "protection mechanism" kicks in.
Download and read this whitepaper. Required reading if you ever plan on taking the CWNA and/or CWSP exam.
http://cwnp.com/learning_center/search_details.php?doc_id=l7w2
I can't seem to get to this document. When I click on "View this document" link it keeps asking me to log into CWNP website even though I am already logged in. I can get to other documents with no problems. -
It's a different login. The site has 2 logins...one is your account the other is strictly for the forums. You need to be logged into your account to view whitepapers. Your account will be an email address + password, forums is a username + password.
-
Brett C. Escribi?3:
It's a different login. The site has 2 logins...one is your account the other is strictly for the forums. You need to be logged into your account to view whitepapers. Your account will be an email address + password, forums is a username + password.
I tried it using just my login name. I can log in with no problem and access my account and practice tests and other white papers but this one.
- 1