unable to decrease response time

[kthned]

hi to all

I am stuck in a problem, we have a aironet 1300 with yagi antenna we get the response but it was very hi i.e 1500 msec

Can any body tell me wat can i do to decrease the response time

Thanks

[wong34539]

High response time can be due to variuos reasons like CRC errors on Radio interface, RF interference Poor antenna alignment and so on. Is the connectivity intermittent? This document will be useful to you to troubleshoot the problem.

http://www.cisco.com/en/US/products/hw/wireless/ps5279/products_tech_note09186a0080508551.shtml

[routerking]

Hi,

Kindly mention more things like...

Are u facing the problem in all ur laptops..Ventor of ur NIC

Are u using two antennas..If no mention antenna position..

Distance between two AP's and channels they are using..

Rgds,

AVAN

[vsnl_chennai]

Hi,

You must work on causes and effect will automatically come :)

To Start with :

1) Yagi are directional antennas , take care of alignment .This is most important .

2) LOS consideration ...

3) for interferance we can use free software like Netstumbler to check whether any other link in working on the same channel or not , if yes change the channel ... Even to cross verify u can use 5 Ghz band to see if the latency is reduced or not, if yes there is a interferance problem for sure.

You can also use the option of Performing a Carrier Busy Test

4) Take care of connectors and proper cable length.

and if this doesn,t solve your problem kinly tell us more about your setup so that we can really solve the problem ..

Regards,

Prakash

[kthned]

Thanks for your replies.

actually we are using Yagi antennas on the remote sites and omnidirectional on the main site. all the remote sites are communicating properly to main site except one site which is <5Km.

Following are the activities that we have performed :

We have made changes to Antenna direction and height and we got high response but after few days it got worse (1500 msec)

Than we replace the antenna the ping response comes good but when we run the application it does not work. I mean the server (As400 on the main site) do not response.

(all the remote sites application are running properly).

[vsnl_chennai]

As u stated that when u changed the direction of the antenna , you got a better respose time that means the better alignment is required ..

Okay let me know how you do the alignement ?

Do you use some software or just a manual one .I would say try to use some real time softaware that give you RSSI and Link quality values so that we can align the antenna as per link quality parameters.

Pinging with some bytes not always give's you correct quality of link that is estabilished between receiver and transmitter radio's.

I will give you a example.

Suppose we aligned the antennas and we tried to ping the other radio with 32 bytes and got 3 msec as latency.lets say we did 30% of the best alignment that we could have acheived. Now with 100% correct alignment suppose we could have acheived 10mbps throughput and with 30% it must be 3 mbps atleast.so pinging with 32bytes of data won't make much sense in latency.

So my recommendation is to use some 3rd party software for calculating the link quality achieved while doing antenna alignment.

Try to get a good link quality and response time will automatically become better.

And after replacing the antenna as you said ,the ping is coming that means the problem is not with RF part.

Best Luck & Regards ,

Bramnha Prakash Tiwari

[rhobab]

Could the other 2 links be monopolizsing the bandwidth? Remember the total bandwidth is divided by 3 because you have 3 links. aslo traffic form the other 2 links may be monopolizing the whole bandwidth