March 19, 2011 Leave a comment
February 27, 2011 3 Comments
Here I am at home today being a good survey engineer and making sure all of my tools are in proper working order prior to going out and having to rely on them for the week when all of a sudden, I’m presented with the following anomaly when I’m exercising my trusty Spectrum Analyzer:
Those of you that are familiar with Spectrum Analysis in general usually expect to see something this bad (high duty cycle) in the 2.4GHz spectrum but not the mid-5GHz spectrum! Having just reloaded my laptop with Windows 7 and installed Service Pack 1, I was in the ‘let’s test it all’ mode to make sure nothing unexpected happens. At this point, I was pretty blindsided by the obnoxious noise happening and the ‘Generic – Fixed Frequency’ tag wasn’t helping me any. At a loss for what this could be since I live an acre away from my nearest neighbor and several miles from the nearest airport, I pinged a few of my friends. They suggested the usual suspects – MRI machine, TDWR, neighbors, etc all of which I explained away by location. Being that TDWR is in the 5470-5725 frequency, I changed my card over to 5.725 – 5.850 and after some time got this equally disturbing read:
At this point, I started to suspect my Spectrum Analyzer since I was using a non-Cisco branded Spectrum Analyzer card with the Cisco Spectrum Expert software (the card I was using had the Cognio components that Cisco purchased and re-branded as their own). So I grabbed a copy of the card manufacturers software to rule out in compatibility and I got the same results.
At the end of the day, I was able to swap in a Cisco branded SA card and my results normalized. Clearly I have a flakey (old) SA card that was giving me improper readings. Lessons learned:
- Always test your tools and keep them in good working order
- Don’t assume that your tools are telling you the truth. If you see something suspect, dig into it and validate against another source
February 27, 2011 Leave a comment
So, it’s been a bit since I’ve been out on a survey proper (not sure if that’s good or bad) and a while back I got some new components in for my rig. I was debating on retrofitting my trusty black Pelican 1510 case with new foam or getting a new one. Never one to spend needlessly, I trickle-down upgraded someone else with my old case and opted for a shiny new tan colored case – As far as I know, I’ll be the only one on our survey teams for the foreseeable future with a tan case so it should make it easier to tell mine apart. So, a new Pelican case, a new battery for my Terrawave survey pack, a shiny new Cisco 1142, and some various other bits an pieces all get massaged into the pick-and-pluck foam of the kit. Revisiting the way I hang my AP during the survey was something I’ve been meaning to address for quite a while. I opted for the 2x 90 degree painter pole arms and a drywall finishing brush (sans bristles) and some good old fashioned drilling to assemble a pretty graceful looking mount:
The intermediary piece attached to the factory mount bracket is the brush head that I picked up from The Home Depot in their drywall finishing section:
After ripping out the bristles, a choice few holes later and my mount was ready! Next to place the battery and AP + mount in the bottom of the Pelican case and outline the pick-and-pluck:
Here is what the bottom of the Pelican looks like with the components nestled in – I coiled my CAT5 network cable around the mount and laid in the two 90 degree arms:
Add a top layer with some space for my spare laptop batteries, the AC adapter and some survey cards and call it just about done:
Now I’m off for a week of surveying!
January 15, 2011 8 Comments
As a followup to my previous post on surveying with Cisco 3502 series Access Points, I’ve been playing around with a few options that ultimately get the job done. As you may recall, the Cisco 3502i Access Points have different radios in them than then 1142 Access Point making the 1142 an unsuitable substitute for a site survey for those customers looking for a literal real-world picture of what a 3502 deployment will look like. Because I have several customers that won’t accept an 1142 substitute survey for a 3502i deployment, I’ve been wrestling with the best way to get this done.
December 19, 2010 Leave a comment
So, it’s been a few weeks since I’ve had a chance to post anything and there’s been quite a bit going on! Firstly, I spent a few days in Atlanta coming up to speed on the Mobile Access VE Solution for low-cost indoor cell repeating utilizing your existing CAT5,6,7 cabling. I can’t wait to get dug into an install – quite a different mindset from wifi to cellular.
After that, spent a few days in San Jose for the Cisco Partner VT meetings and learned about all sorts of up coming new stuff from Cisco that can’t be talked about yet – infact, that’s probably the biggest reason that I’ve been somewhat quiet recently – being wrapped up in NDA style information makes it hard to be social.
Contribution to the https://www.myciscocommunity.com/ page netted me a Cisco Cius when they’re available. Thanks to Vic Nunes for making that happen!
Upcoming in March (17th and 18th) is the Wireless Tech Field day in San Jose that I’m quite excited to be a part of! The fine folks over at Gestalt IT that put on the ‘regular’ Tech Field day have teamed up to host one specifically focused on wireless technologies. I was selected as a delegate and look very forward to my first Field Day. I think the list of presenters is being firmed up but I’m glad to hear about the ones that are lined up! Details on the event are at:
Looking forward to meeting Stephen Foskett and hanging with wireless powerhouses like @jenniferlucille and @MarcusBurton among all of the other delegates that have confirmed.
December 19, 2010 Leave a comment
So, rumor has it, if you put your 3502 in H-REAP mode, and statically assign your IP address and your default-gateway as your static host IP address, you can survey. Need to try this when I get back to civilization in January. I expect this will require some sort of loopback slug and a POE pass-through. Gonna have to bust out the crimpers!
October 25, 2010 2 Comments
When a Hybrid REAP access point enters into a standalone mode, the following occurs:
•The access point checks whether it is able to reach the default gateway via ARP. If so, it will continue to try and reach the controller.
If the access point fails to establish the ARP, the following will occur.
•The access point attempts to discover for five times and if it still cannot find the controller, it tries to renew the DHCP on the ethernet interface to get a new DHCP IP.
•The access point will retry for five times, and if that fails, the access point will renew the IP address of the interface again, this will happen for three attempts.
•If the three attemps fail, the access point will fall back to the static IP and will reboot (only if the access point is configured with a static IP).
•Reboot is done to remove the possibility of any unknown error the access point configuration.
Once the access point reestablishes a connection with the controller, it disassociates all clients, applies new configuration information from the controller, and reallows client connectivity.
September 21, 2010 Leave a comment
September 14, 2010 Leave a comment
September 9, 2010 Leave a comment