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Network Janitor: How the Elements Can Effect Your Network (by Tony Fortunato)

Tony_fortunatoThe_tech_firmAuthor Profile - Tony Fortunato is a Senior Network Specialist with experience in design, implementation, and troubleshooting of LAN/WAN/Wireless networks, desktops and servers since 1989. His background in financial networks includes design and implementation of trading floor networks. Tony has taught at local high schools, Colleges/Universities, Networld/Interop and many onsite private classroom settings to thousands of analysts. Tony is an authorized and certified Fluke Networks and Wireshark Instructor. His Pine Mountain Group CNA Level I and II certification demonstrates his vendor neutral approach to network design, support and implementations. Tony has architected, installed and supported various types of Residential Wireless High Speed as well as hundreds of WIFI hotspots. Tony uses a variety of technologies from Powerline, Wireless and wired technologies to find the most cost-efficient and reliable solution for his customers. Tony combines custom programs, open source and commercial software to ensure a simple support infrastructure.

 Corrosion (Large)

I was asked to investigate a mysterious issue for one of my customers.  It seems that one of the Access Points would loose power and had general performance issues when it did work.

The vendor told them that wireless performance can vary depending on their RF environment, and dismissed the complaints, but they knew that this was considerably slower.  They tried various channels, changing from Horizontal to Vertical Polarity and modifying the channel width with no success.

First thing was to check the switch and access point port settings and they were consistent with the other AP's, so that wasn't it.  We verified the firmware in all the AP's and all were the same, current builds; strike 2. Then we checked the switch port and saw many interface resets and physical level errors.  Strange indeed.

The customer explained that they noticed the same thing and suspected a faulty AP, so they replaced it and the errors never went away.  I went over, unplugged the cable that went to the switch port and noticed it was corroded and oxidized. I asked to see some of their patch cables and noticed many of them were in the same condition.  "Odd", I mumbled to myself.

In this photo above, the good connector is on the left and the corroded one is on the right.

It took us a while to figure out why the cables were in the current bad state.  Due to space constraints, they stored their cables in the factory which was not environmentally friendly.  The high humidity, oxidized the RJ45 pins causing the connection to fail, or errors. 

One of the technicians confessed that sometimes when they troubleshoot a problem on the factory floor and replace a suspected 'bad' cable, they don't test it and the bad cable may have worked its way back into their stock.

Then I went for one of my famous (or infamous) walks and found some CAT5 indoor rated cables on the outside of the building.  I told them that if you choose to use indoor cabling outdoors (not recommended), you must minimally use a conduit of some kind to protect it from the elements.  I went on to explain that outdoor rated cabling has a different jacket and some are gel-filled to protect against the elements.

Upon further inspection we found evidence that some of the cable jackets were starting to fail as shown in the photo below.

Cracked (Large)

They admitted they weren't entirely aware as to why the 'outdoor' rated cables were more expensive and now it made more sense.  We proceeded to replace several cables while I was there.

I also noticed that one of the outdoor AP's, weren't weatherproofed and was told that is was ok because it was in an enclosure.  It turns out, that the enclosure was a plastic toolbox, not really a weatherproof or NEMA rated enclosure. I explained that moisture and humidity will get in there and have the same effect on the connector.  I showed them that a dab of dielectric gel on the RJ45 will provide some protection, but a proper outdoor rated AP is the proper solution.

So if you have places outside of your office where you need to have ethernet connectivity, it is in your best interest to inspect it and ensure the proper cables are used.



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