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Yes as all have said, it is time for a spectrum analyzer:

Hope you don't have too many of these remotes or something similiar jamming your wireless: some boats may have them for emergencies.

http://www.uniden.com/products/productdetail.cfm?product=whamx4

http://www.uniden.com/products/productlisting.cfm?cat=Marine%20Electronics&filter=Wireless

Almost forgot... since your access point is a 1240 , does it support an an A radio? Try that and see if you get the same results.

Did anybody come up with a solution or fix. I am at one of our offices and they are experiencing the same issue. They are Cisco 1232, no A radio, rev 12.3(4)JA. Using WiSpy 3.1 is showing no significant noise or rouge signals, AirMagnet Laptop Anylyzer shows the signal drop to nothing. Checked the logs on the AP's and they a disassociation and then a reassociation.

Any ideas?

David

What "views" are you guys using in Wi-Spy? I can't think of it off hand, but if you use the default views, even a microwave oven at 2 feet away won't show anything significant. You have to add a view... sorry I can't remember it. My tablet is at home so no dice.

Put a cup of water in the microwave and turn it on. If you are using it correctly, you will see the graphs and charts fly off the handle.

Let's make sure you are using the spectrum analyzer correctly first.

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If the packet capture you speak of is correct, something is wrong with the STA behavior. A STA shouldn't initiate a disassociation if it hasn't roamed to an new AP. A packet capture + spectrum analyzer is the next step to answering these problems.

GTHill

I had the same issue on my wireless network using Cisco 1230 Series AP's.

The fix turned out to be configuring and enabling Multicast routing on the Cisco switches.

There are many Cisco articles and configs available on the vendor web.

You only need to determine how you wish to set up the multicast network and enable on the ports where AP's are attached.

Hope this helps!

rgregory Escribi?3:

I had the same issue on my wireless network using Cisco 1230 Series AP's.

The fix turned out to be configuring and enabling Multicast routing on the Cisco switches.

There are many Cisco articles and configs available on the vendor web.

You only need to determine how you wish to set up the multicast network and enable on the ports where AP's are attached.

Hope this helps!

I will see if I can find my old configs. I no longer work at that location and it has been a few years since I corrected the issue.

The clients were not roaming, they were simply deauthenticating and reauthinticating on the same AP's.

my company had a very similar problem where our RF guns were being kicked off the network, and they also had roaming issues.

Come to find out, the multicasting and our VoIP 3Com phone system was doing it. Any time there was a conference call the RF guns would go haywire, as they were on the same VLANs as the VoIP system. The fix had something to do with the multicasting, but it was above my pay salary as far as what the exact fix was, this was handled by the Sr. System Admins.

I know this doesnt help much, but I can try to get with our systems team and ask if they remember what the deal was, or if they have the paperwork along with any case information that was documented with Cisco.

Our APs are Cisco 1240 series a/b/g

Hii ,

Can you console into the AP and check for the logs.Is the radio flapping ??

Thanks

Sorry for not replying sooner but finally got back in the states.
My original concern was that the POE switch might not me able to handle the current for the AP?¡é?€??s, if I remember correctly you originally stated 22 AP?¡é?€??s with a controller.Some older 802.3a/f switches could only handle ?¡é?€??x?¡é?€?? amount of AP?¡é?€??s.So if you?¡é?€??re running 9 devices (AP?¡é?€??s/repeaters) you should be OK.
To check this read the Cisco logs and see if the AP powers down the radio, and then re-enables it.

Now on the possible marine issues.

1)Boats do not have a real ground as in terrestrial electrical systems. Meaning that it is quite possible to have a shorted piece of equipment providing low current (AC/DC) to the hull. If the AP?¡é?€??s are not insulated from the hull this could be a problem. You can check yourself if there is current on the hull with a multi-meter. Probably the boats electricians would notice anything above 20V and, or 1A, but anything else might be within there operating parameters. However 10V @.01A could definitely impair an AP. This would bypass the AP?¡é?€??s logs but would only be apparent by watching the RF signal. Also if any of the antennas are outdoors and the lightning arrestors are bonded to the hull instead of ground this could be the cause as well as being against code.
2)RF interference caused by either radar or communications equipment. This interference could either be over the air or via the hull to an un-insulated AP. You would need to use a spectrum analyzer to see this. I know it might seem hard to believe that 3 &10cm radars could cause interference (9 & 3MHz) respectfully but what matters is how the transmitter builds the signal. Signal leakage from a 60kW radar would kill your WLAN. If the signal generator was based on a 600kHz clock the 4th harmonic would hit right in the middle of the 2.4Mhz band. The same could be true of the communications equipment, figure marine band, shortwave ect; even an onboard cell network node could potentially cause an interference issue. However it happens both at sea and in port, normally in port the radars would be off and probably the radio transmitters too. So I would tend to suspect the former as being your cause of the loss of RF signal.

Good Luck!!!


BTW I?¡é?€??m not sorry about the Australian rock band reference! AC/DC rulez!