Color Codes

With the help of everyone on this forum, I’m starting to get this stuff. My next question is on Color Codes. I understand that in order for a SM to register with an AP, they must both have the same color codes. My question is why you would do this? Wouldn’t you want the sm to register with whatever ap it can find, or do you really want to limit your sm’s choices.

This question was brought up because we noticed that a few of our sm’s are hopping around to different ap’s even though their numbers look good. I called tech. support and they said that the sm would only change ap’s if there was something wrong with the signal but, I’m not seeing that. Have any of you experienced the mysterious sm hopping? If so, is that why you use color codes and nail each sm to 1 ap?

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We use ONE color code per AP Cluster, then we choose different fre’s for all the AP’s within the cluster. You choose the correct Color Code and the correct Freq and you dont have to worry about the SM hopping to another AP. You can do this by mapping the customer on any mapping agent in coordinance with your AP cluster.

We use to leave all 3 (that we used) Freq’s checked but found that some SM’s no matter how strong the signal is hopped from AP to AP causing the customer to go up and down as it re-regs to the different AP.

In MOTO’s theory, they state that the SM will register to the strongest signaled AP out there. We have to disagree. We have some SM’s that would be great on one SM and then mysteriously re-reg to another AP and have a horrible signal. This is how we found this problem as our monitoring system would pick this up and alert us that a customer was having issues.

So as it is today… we have ONE Color code per cluster… then on the SM we pick ONE FREQ on the SM and then when it is installed if it is border line between two… we will check and un check FREQ’s to see what the strongest signal is from each AP.

Make Sense? anyone else doing it this way?

CelerityNetworks wrote:
In MOTO's theory, they state that the SM will register to the strongest signaled AP out there. We have to disagree.

If an SM can see multiple AP's where the color codes are the same and the SM has multiple frequencies selected it will choose the AP with the lowest Jitter. Jitter is king in AP selection. (celerity- please let me know where you heard or read that AP selection is based on signal strength)

That said an SM will not hop to other AP's randomly if it is session. When it looses the session with the AP it will then look for a new session and when it is looking it is going to register to the AP with the lowest jitter.

Regarding reasons for using one color code verses many....its really up to you. I have heard arguments for both uses. First, if you want to lock down your SM's so they are going to their best AP at install then you use a different color code for each AP. Keep in mind that in the event of an AP outage the SM's will be stranded and unable to register to another AP. This is why some use a single color code per tower. When an AP drops the intention is that the SM's will register to another AP.

This introduces a little bit of a network management issue as when the preferred AP comes back up all the SM's will stay registered to the secondary AP that they failed over to. In this case you would need to reboot the secondary AP to force all the SM's to re-register and get back onto their preferred AP.

Hope this helps.

I will have to disagree with Support on this one. I have specifically seen an SM rereg to another AP with a lesser RSSI, Jitter and dB level.

It does not really matter as far as I’m concerned. Each of my APs has a unique color code.

I do that for the same reason I don’t like automatic transmissions, anti-lock breaks, and on-demand four-wheel-drive: I perfer to make decissions myself, not leave it up to some piece of software.

We also use different color codes for ea Ap, We didn’t start that way we started with the same color code for everything we found that if an Ap goes down the customer would switch to a different Ap. sounds great but they won’t switch back to the stronger one unless the sm is power cycled or rebooted.

So the customer is putting up with poor service until it is switched back.

We also have a differant Ip string to ea Ap it’s a little hassle but really helps if you are looking for a problem. The Ip tells you exactly where the customer is located.