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Mixing a/b/g and n aps

Dear All,

Will it work if i keep 802.11 a/b/g and 802.11n ap's under same 5508 controller...? what are the impacts...?

VIP Purple

Mixing a/b/g and n aps

Yes, it will work.

To improve the wireless performance, you can disabled low data rates (upto 11Mbps) disabled under each readio band.


802.11b/g/n (1, 2,5,5,6,9,11 - disabled, 12- mandatory, others - supported)

802.11a/n (6,9 -disabled, 12 -mandatory - others- supported)

If it is high desnsity environment & AP are closeby, then you can make 24Mbps mandatory & all lower data rates disabled. Keep in mind multicast traffic will get highest mandatory data rate configured.



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Re: Mixing a/b/g and n aps

Factors that Affect 802.11n Throughput

There are circumstances where 802.11n devices cannot operate at their       maximum capable data rates. There are various reasons why this occurs. This is       the list of factors that affect 802.11n throughput:

  1. When 802.11n clients operate in a mixed environment with 802.11a or           802.11 b/g clients, 802.11n provides a protection mechanism to interoperate           with 802.11a or 802.11 b/g clients. This introduces an overhead and reduces the           throughput of 802.11n devices. Maximum throughput is achieved in           Greenfield mode where only 802.11n clients           exist.

  2. Factors such as Channel width, Guard Interval and Reduced IFS (RIFS)           play a major role in the bandwidth.

  3. Clients ability to send a Block Ack instead of individual frame           acknowledgements.

  4. MCS Index configured on the WLC.

  5. Proximity to AP—Clients closer to the AP experience higher data           rates. As clients move farther away from the AP, signal strength reduces. As a           result, data rate decreases steadily.

  6. RF environment—Amount of noise and interference in the environment.           The less the noise and interference, the greater the bandwidth.

  7. Encryption/ Decryption—Encryption in general reduces the throughput           due to the overhead involved in the data encryption/decryption process.           However, advanced encryption standards, such as AES, can provide better           throughput when compared to other encryption standards, such as TKIP and           WEP.

  8. Wired Network Infrastructure—Bandwidth of the wired infrastructure           determines the speed of the traffic to and from the wired network to the           wireless clients.

  9. If using an AP1250, change the AP to H-REAP mode for a 5-10%           boost.

  10. If using an AP1140, keep the AP in local mode and enable TCP MSS on           the controller. Use the config ap tcp-adjust-mss enable all           1363 command in order to enable it.

  11. Disable RRM scanning to prevent any throughput drops           when going off channel. This can yield a 1-3% improvement.

  12. Disable RLDP to ensure the AP does not attempt to connect to rogue           devices during testing.

  13. Use a Wireless Controller 5508 as the data plane is superior to the           4404-series

Hall of Fame Super Blue

Mixing a/b/g and n aps

Will it work if i keep 802.11 a/b/g and 802.11n ap's under same 5508 controller

My priority as to which APs go to which controllers depend on the site.  I want all APs in a single site go into one controller (regardless of models) to avoid users doing inter-controller roaming. 

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