Wireless table meanings and values

I have some hopefully simple questions using mikrotik rb711 and an 802.11 b/g/n access point. When I look at the registration table some numbers do not make sense and or what is a good value range?

TX/RX Signal shows
0/-74 why do I see a 0 for TX on my rb4ll I just see -73?

TX/RX CCQ is this even worthlooking at? I have found mixxed answers and if it is valid for b/g/n then what is the lowest best number you want to achive?

P Throughput I assume higher is better however what if client is only connected and doing nothing then it would show a low number?

Signal Strenghths what does that mean?

TX/RX Rate I see some client connectd at 36.0mbps/24.0mbps while others say 1.0mbps/20.0mbps. Does it show 1.0 beacuse no data is coming through or is that what they are actally connected to it with and why would the TX be so low and rx so high?

Any input would be great

As far as i know,

The TX/RX rate, CCQ and the Signal level depends of the traffic its passing by through the link, it has to be some traffic to give you a more certain data.
P Throughput its, if im not bad, its the possible Throughput available with those wireless conditions.

TX/RX Signal when you have a CPE from another brand, ie. Tranzeo, you will get only the value of the AP so will be RX., its telling you that the AP “hears” the CPE with -xx dBm.

Am i right? or i misunderstood your question?.

best regards.

I think I got the just of it but what would be the best worst numbers to see? Before link becomes unusable?