Cisco AP

[Orkhan Hajizada]

Hello! Does  Tx Power Level affect on AP range? What's best practise for it?

And in what order levels are? The 1 level is the strongest power tx powet? 

[Rich R · Accepted solution]

> Does  Tx Power Level affect on AP range?
Yes

> What's best practise for it?
Conduct a full site survey with appropriate power levels set according to the design specifications. Generally speaking you should not be using power level 1.  Also remember it's no good having high power from an AP that can reach far if the return signal from the client cannot reach back to the AP.  High AP power can also cause or aggravate the https://en.wikipedia.org/wiki/Hidden_node_problem

> And in what order levels are? The 1 level is the strongest power tx powet?
Power level 1 is the highest.  The actual power will vary according to AP, antenna, channel and regulatory domain.

[Haydn Andrews · Accepted solution]

The Cisco Power levels translate to dBm or mW values, Cisco used them as some channels can utilise higher dBm values and also differences between reglatory domains.

Whilst increasing the power level will increase how far the AP can be heard it does not increase how well it can hear - think of it of I have a loud speaker to talk accross a crowd but you don’t, you will hear me but I wont hear you.

Generally the practice is to look to keep the AP power levels within 3dBm of the clients capability, a general practice is to utilise 25mW as the design.

I normally then configure RRM to use 11-17 dBm for the power levels which allows the APs a few levels to increase and decrease, but I then follow it up with a site survey using tools like Ekahau.

[Orkhan Hajizada]

@Haydn Andrews  @Rich R  Thank you for your answers! One more question. Does the 1 power(the strongest)  affect on something on AP? Maybe lifetime of AP?

[Rich R · Accepted solution]

> Does the 1 power(the strongest)  affect on something on AP? Maybe lifetime of AP?
No, it should not.  I'm certainly not aware of any evidence that it does.  Quality of components used seems to be the main determinant of AP lifetime.  WiFi transmit power is pretty low in absolute terms, even when at max level (as per Haydn's answer), so there's no reason why the power level should affect AP lifetime.

[Orkhan Hajizada]

Thank you!