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B. Rdgs

From my knowledge we currently do not have a Cisco MESH network running, From my latest information from Cisco I would recommend you have the latest software running, Moving to the 1522 is also a good choice. Another recommendation would be to have a spectrum analysis done at the site. I would hope this would have been done during the survey.

Depending on how irregular the ping is , this is somewhat normal for wireless devices.

You might also try going to supportforums.cisco.com for some help.

Thks Paul, for your comments, we will do a Spectrum Analysis

Hello Jose,

I’m still a bit sceptical when it comes to MESH. Today there is no standard yet for MESH and several manufactures are implementing their own interpretation of the technology. Also, there are already several generations in MESH technology.

There are not many MESH implementations in ports. The ones that I’ve heard about all have issues with the technology. Of course, MESH manufactures need the early adopters to get the technology to mature level. The technology sure has interesting features, but in all honesty, I believe it is still a bit too early.

I’m looking forward to hear about the progress on your site though. So if you don’t mind to post some updates as you go along that will be much appreciated.

Thks, Pascal, for your comments, Do you know any port that have installed this technology (CISCO MESH)?

Hi Jose,

We have a rail yard here in Canada where a third party hired Cisco to install a MESH infrastructure using 1522 APs.  The system consists of 8 wireless APs using 2 wired APs.  All APs use 3 omnidirectional 2.4GHz antennas and 1 omdirectional 5GHz (for the backhaul).  This site has struggled to get consistent operation.  There seems to be a lot of RF signal but devices are unable to send\receive data when the RSSI on the terminal gets down to about -65dbm or so.  From the debugging we have done it seems like the coverage that the omni-directional antennas are providing does not work well to get around the stacks of containers.  We also question whether the 5GHz MESH backhaul works consistently.  We also question is some of the problem is due to the external noise the Cisco backbone is picking up.

One of the problems we have at this site is that we do not have the ability to make physical changes to the backbone since a third party installed it and has control over it.

Some of the changes that we have made which improved things a little were to tilt the antennas (APs) down to concentrate the beam of the antennas into the yard a little more.  You need to be careful doing this because it can cause problems with the backhaul.  We also upgrade the Cisco controller software to version 5.xx.xx (I am not sure of the exact version).

thks, Paul,  we are in the same problem (external noise), in my case the external noise is caused by other 2.4 Ghz Wireless Network.  regarding to the physical changes, we were made several changes as:

1.  Change some AP's from 1510 to 1522 in order to implement the Diversity, but this change don't work fine

2. Move down the 2.4 Ghz antennas  from 24 meters to 16 meters leaving the to 24 Meters the 5Ghz anttena for the backhul work fine

3. In some cases we have changed the omni anntenas to sectorial antennas

4. We have created in network controller the zone groups for to force the AP's to connect only with the AP's in theirs same group

Actually Ciscon recongniced an issue with the AP's  (see bellow the cisco posted)

I have filed bug CSCtf84606 to address this issue.

I am providing our software engineers with the information that you have provided in hopes of fixing this issue.

The trigger seems to be low SNR ratings on the Map's upstream connections.

Can you take a look at your problematic Maps' snr to their upstream Mesh peers and try to improve their signal quality?

This will be a temporary workaround until we can get the issue corrected.

Hi Jose,

If followup of Paul's comments, The Canadian Railway that is trying to implement the Cisco Mesh upgraded their controllers to version 6.0. They are running manual power levels (level 5) and manual channels. running powerlevels any higher, and the AP's report the clients much weaker than what the client sees the AP at. I remember reading that Cisco recomments a height of 35', so 10Meters. Only problem with this is that in Ports they stack containers much heigher than that. I know that they have trouble with the backhaul not always picking the best route, so they play with power levels to get it to pick the best path. We still see issues where there is great signal, but no data gets through and the terminal will drop a lot of pings. We were actually planning on using Sector antenna's, but putting them 25 meters up with downtilt to get a better signal, did you notice any improvement with that route?

John.

Hi John, thks for your comments, when we installed this new technology CISCO MESH, we did a big error, we installed the AP a height 24 meters and only where can put AP RAP (Network fiber optic), we think that installed it on this height  could help us in solve the best route the backul (over the stack container and same height of RTG crane),  it wasn't successfull, we have tried the follow:

1. Put the the 2.4Ghz anntena to a height (16meters) and 5.8 Ghz antenna to a height (24meters), we think that leaving the 5.8 Ghz the backul could generate a best route between RAP and MAPS

2. in some yard areas we have intented to install sector antennas, but give a direction to the signal

3. we have creating segment group on the controller, for force the MAP can connect to RAP of this segment

But the all the ideas have not been successful,  and now we have detecting a new problem, the AP are blocking (no responds they didn't give signal 2.4 and not 5.8) this error is recognized by cisco..

actually we're thinking to change of tecnology like ARUBA or Motorola MESH

Enrique.

so have you narrowed the issue to poor Backhaul performance, or poor 2.4 client side performance. I've been focusing on the client side because the company managing the MESH keeps saying they have a good backhaul like and that they get all their pings back. the issue I see is that Omni antennas do not work well in outdoor environments and that having a sector antenna at 24 meters or even higher with downtilt provides much better coverage. We also force the clients to Bmode only,as G has a tougher time with noisy air.  Also the new issue of blocking 2.4 and 5.8, what software release is this in? does this happen frequently?

our release in the cisco controller is 4.1.192.35M,  these events happens almost 3 o 4 times on the week. in diferent AP's (RAP or MAP)

Now, we're waiting that CISCO release the new version with the solution

meanwhile we're buying new devices for RTG with teklogix Narrowband network (8525 device and 9160 Norrowband Controller) and for human handheld (workabout g2)  we're change the specification install the GPRS module and stablish the communication over VPN and Cellular Network

And the next step is evaluate other wireless technology

We found that release 6.0 make a big improvement

HI John, could you comment the improvement that you found on release 6.0?

One was that the back haul link test actually worked and the second thing was that the back haul liked to run on slightly less power. We also noticed that when the auto power level was used for the client side, it went to power level 5 where it was using power level 3 prior. Being able to run at a lower power level provides better throughput and performance on both sides.

i've investigated with our network administrator, he commented that we can't update our cisco controller to release 6, due that this release don't support AP 1510, and actually in our mesh we have a mix to AP 1510, 1520 and 1522

:(