Cisco Aironet 802.11a/b/g Wireless CardBus Adapter. Of 802.11 connectivity. And simplify wireless LAN deployment and management. In memoriam of the first amendment to the IEEE 802.11. 802.11b device by using a wireless USB adapter. 802.11b data rates.
So let me start by apologizing for not 'getting' what you're saying because I see a few different things that were all talking about. The captures and how you names them cleared things up a bit. I believe we are all talking about a few things and you're looking for a specific answer.
Please let me know if this short list is where we've ended up or a wrong perception: 1) What does the WLAN Radio Policy actually do when configured from the WLAN section of the controller? 2) What does changing the data rates in the settings of the 802.11b/g radio result in? 3) What causes a station to not be able to connect based on settings on the controller. My humble 2 cent responses: 1) WLAN Policy does not set any parameters on the radio or how it behaves. I believe you are simpy given an option to apply WLAN (General, Security, QOS and Advanced) parameters on a particular Radio.
The Radio policy configured in a separate place will dictate how the radio behaves and talks. I think of the WLAN Radio Policy of more asking 'Where do you want me to apply these parameters?' 2) Both your captures titled G Only and BG beacon showed that you had 1Mbps data rate set to mandatory.
802.11 B G Usb Wireless Adapter Driver
I'm assuming that those captures were named based on how you had the WLAN Radio Policy set and not how you had the data rates set on the radio itself. This will never change until it's changed on the 802.11b/g radio parameters no matter what you have the WLAN Pollicy set to.
The radio will beacon showing every data rate available and pass along mandatory rates at the same time. This will be done for every WLAN that has a Radio Policy for that radio. 3) We can clearly see that when you set the 802.11b/g radio to have a mandatory data rate of 1Mbps and 18Mbps, the phone would not connect since it could not support the rate.
Again, I apologize if I'm missing the boat but I'm trying to learn here too If I'm competely wrong, please let me know as I welcome the feedback. Maybe I wasn't clear. I understand how to disable the data rates in order to block off B clients. That isn't my question.
I want to know what exactly happens when selecting G only on the WLAN. From what I have seen It still uses the B rates so clearly it isn't disabling the B rates in order to make it G only. Does it just ignore B clients trying to join, does it tell the B client it can't join? Why does it matter? Because the data rates are a global change (at least pre 7.2).
So if I have 10 WLANs that need to be G only and one that needs to be B only (B only WLAN would be the only WLAN on the AP, no shared WLANs). One would think you could set the WLANs and not have to take B rates' airtime wasting hit. To mix it up 7.4 now has an 802.11N only RF profile. Does this mean greenfield or what?
You can configure an access point to work in an 802.11n-only mode for an access point group base. In this mode, the access point broadcasts support for 802.11n speeds.
Only 802.11n clients are allowed to associate with the access point. Configure the 802.11n-only mode by entering this command: config rf-profile 11n-client-only enable rf-profile-name For more information, see the Configuring RF Profiles chapter of the Cisco Wireless LAN Controller WLAN Configuration Guide, Release 7.4. The b/g policy allows both.11b and.11g clients to associate. The g only policy rules out any.11b clients from joining. I’m not sure why we have this policy setting on the network when you can accomplish the same thing by disabling all the.11b rates and keeping the.11g rates enabled. Changing the policy causes all the APs to reboot and rejoin.
Changing just the rates does not require a reboot or rejoin of the AP. A clarification: There is no such thing as a “g only” client. All.11g clients must also work on.11b only APs or using only.11b rates. So a.11b device is a subset of a.11g device. Any rates you set as mandatory on the network must be supported by all clients you expect to join the network.
Scenario:1 I’ve one data rate set as mandatory on b and g rate. Both b only and g clients can connect. Scenario:2 have one data rate set as mandatory on b rates only - all clients can join,.11b and.11g. Scenario:3 have one data rate set mandatory on g rates only. only.11g clients can join. Supported rates are rates that the client and AP can actually send data packets between each other (directed traffic), depending on how good the link is currently. Guys, I understand how G and B work and disabling the data rates.
That is not my question. That still doesn't explain how the controller stops the B clients from joining. For example when you set the max users per AP in 7.2 code the AP will tell the client it is full and won't let it join, the client moves on to the next AP. I figured someone would know the answer off of the top of their head. I guess I need to dig out an old B client and sniff it. I think I have a B device around here somewhere. What does this have to do with B rates?
If max user or load balance is enabled one of two things happen. Either the AP ignores the probe request from the client OR the ap responds to the client with a REASON CODE 17. Thefranmanatt wrote: Guys, I understand how G and B work and disabling the data rates. That is not my question. That still doesn't explain how the controller stops the B clients from joining.
For example when you set the max users per AP in 7.2 code the AP will tell the client it is full and won't let it join, the client moves on to the next AP. I figured someone would know the answer off of the top of their head. I guess I need to dig out an old B client and sniff it.
I think I have a B device around here somewhere. 'Satisfaction does not come from knowing the solution, it comes from knowing why.'
- Rosalind Franklin 'I'm in a serious relationship with my Wi-Fi. You could say we have a connection.' Thefranmanatt wrote: People are reviewing data rates and saying to turn that off to disable B, etc. I just want to know what really happens when you change that option. You are right about the reason code 17 for max users.
Turn what off? The DSSS rates? 'Satisfaction does not come from knowing the solution, it comes from knowing why.' - Rosalind Franklin 'I'm in a serious relationship with my Wi-Fi. You could say we have a connection.'
The b/g policy allows both.11b and.11g clients to associate. The g only policy rules out any.11b clients from joining. I’m not sure why we have this policy setting on the network when you can accomplish the same thing by disabling all the.11b rates and keeping the.11g rates enabled. Changing the policy causes all the APs to reboot and rejoin. Changing just the rates does not require a reboot or rejoin of the AP.
A clarification: There is no such thing as a “g only” client. All.11g clients must also work on.11b only APs or using only.11b rates. So a.11b device is a subset of a.11g device. Any rates you set as mandatory on the network must be supported by all clients you expect to join the network. Scenario:1 I’ve one data rate set as mandatory on b and g rate.
Both b only and g clients can connect. Scenario:2 have one data rate set as mandatory on b rates only - all clients can join,.11b and.11g. Scenario:3 have one data rate set mandatory on g rates only. only.11g clients can join. Supported rates are rates that the client and AP can actually send data packets between each other (directed traffic), depending on how good the link is currently. Saravanan, In trying to get a B only client to on my network to test I was unable to get my 7920 phone to join. Yes I re-enabled all the B rates with a man rate of 1Mbps.
The phone was giving me an auth error. So I found an old 350 card and put it in to the PCMCIA slot of my old laptop running windows 7. Windows 7 showed the WLAN but it had a red X next to it. When you click it says the following.
'The capablity of your network adapter does not match the requirements of this network.' At the time I had a second mandatory rate of 18Mbps. In setting all the G rates to supported the both clients were able to join. So both of my B clients did NOT like a mandatory G rate and would NOT connect. Can you retest your Scenario:1? Why do you state this.
I want to know what exactly happens when selecting G only on the WLAN. From what I have seen It still uses the B rates so clearly it isn't disabling the B rates in order to make it G only. Does it just ignore B clients trying to join, does it tell the B client it can't join? What have you seen that shows B rates when B is off?
'Satisfaction does not come from knowing the solution, it comes from knowing why.' - Rosalind Franklin 'I'm in a serious relationship with my Wi-Fi. You could say we have a connection.' I want to know what exactly happens when selecting G only on the WLAN.
From what I have seen It still uses the B rates so clearly it isn't disabling the B rates in order to make it G only. Does it just ignore B clients trying to join, does it tell the B client it can't join? It doesn't allow 'B' clients to join.
These are two separate things. Radio policy and data rates. With the newer code you can specify the data rates in the rf profile and apply that to the ap group. Default group will of course default using the global data rates configured.
Well all ap groups unless you specify another rf profile. So if you have a b client roam from on ap on an ap group that has b rates to another ap on a different ap group that has 11 Mbps and lower disabled, the client will drop of course. So just remember that the radio policy and the data rates are two different functions.
Sent from Cisco Technical Support iPhone App. I digress but the word 'policy' apears in MANY places in the controller config.anyway. The Radio Policy in the WLAN configuration is the sum of the General, Security, QOS and Advanced parameters you have configured for that particular WLAN. Specifically, the controller will apply that policy to All (802.11a/b/g/n), 802.11a only etc. Given that there are no actual 802.11a RADIO parameters in the WLAN Policy, I don't know why it would affect connectivity outside of what's configured in the WLAN specifically.
Under the Wireless Configuration, we are given the oportunity to configure Radio Policy. For example under 802.11b/g we can set specific data rates.
If we disable 1,2,5.5 and 11, we know that only OFDM modulation is being used. So if we think about a linear flow: The WLAN Policy is used 'on top' of the Radio Policy.
With all the confusion around this (myself included) as well as the inherint limitations, newer controller code allows up to build specific RF Profiles now that can be aplied at an AP Group level allowing us to control the RF energy, modulation and performance to specific areas rather than at a Global Controller level. I still don't like the way it's done simply because of the 'Verbiage on the screen' but we can at least control the RADIO policy allot better. Screen shot below from version 7.4.100: //art. When set to G only, during the assoc rsp the STA is denied because it doesn't support all rates. It also looks like it changes the G slot times from 20 microseconds to 9 microseconds (G mode short slot time bit set to 1).
I set the profile back to B/G and made 1Mbps and 18Mbps mandatory. Again the 7920 won't join. It gets the same deny because it doesn't support all the data rates. It also sets the G mode short slot time bit.
This pretty good information. I have a lot of sites stuck on WiSM1s and 4404s so I can't use RF groups (don't support 7.2 code). We normally have one WLAN that has some B only hand scanners.
It looks like if I set the WLANs that don't need B to G only I can use the better slot time. I have the captures, I'll post them if anyone wants to look at them. Here is some more in on the topic.
I have a Cisco Aironet 802.11 a/b/g Wireless Adapter that appears to have stopped working. When I plug it in, it doesn't appear to be working and it slows down/freezes whatever I have open on my computer.I do not have the internet and need to use WiFi for internet access.The driver is intalled;; Driver Provider: Microsofft Driver Date: 07/01/01 Driver Version: 5.1.2600.0 Digital Signer: Microsoft Windows Publisher and the driver files are located: c: windows system32 drivers pcmcia.sys I do not know if the driver needs to be updated to the latest version.REMEMBER THAT I DO NOT HAVE THE INTERNET SO.How can I update the driver without having an internet connection. Is there another way besides connecting my computer to another computer to download the latest drivers.