Network Wiring

The CAT6 wiring was just installed.  The linksys that I have was just purchased six months ago, but as far as the router goes, it is kind of old.  I was under the impression, however, that CAT6 cable could run on older equipment, but it would just be limited to 100 mbps.  Am I wrong in this understanding?  

no, not at all.  The cabling, in its most primitive design, is just like earlier revisions.  The new Cat6 (and now even Cat6a) has been tweaked at the electrical engineering level to better resist noise and to carry more data at greater speeds.  So your thoughts are right, Cat6 is a 10GBaseT cable (that a strong 10Gbps that it can carry around for you) if everything is running Cat6.  With older wiring and/or equipment the rating of the network steps down to the lowest component.  The whole "chain is only as strong as its weakest link" argument.  So if your network is limited by the least performing component, which sounds like it could be the router in your instance.

As for why it would start acting up now though, I might consider (like I mentioned before) cable placement.  We had a bloke run 40m of Cat5e literally flat along side a high voltage main power line, then couldn't figure why it would keep crashing the switches when he plugged it in.  If this was a top notch install, they certified the cables after placing them (noise test and the whole 9 yards).  If the final cable install is certified then its all good to go.  If, like more and more service places theses days, they just laid the wire and checked to ensure it was terminated properly then you problem could easily be in the environment noise surrounding the cable.

The problem with this argument, though, is that there are multiple drops at the exact same place.  To give you a little bit better of an idea, I have two network ports at a location, one terminates to my wireless router and one terminates to my wired router.  They are both in the same physical location, so if one of them got interfered with noise-wise then both of them would, causing both of these cables to result in the same behavior.  However, this is not happening.  

humm, your right, that does change the scope of this question a tad.  In your original post you said that when you switched out the AP and router, the device on the Cat6 line is the one that fails (the router now, and the AP when switched).  Am I understanding you right here?  I ask only because that points back to the physical wire and not the equipment.

If I misunderstood and its the router that fails each time, then we're looking at a hardware problem.
The old wiring, can I assume its Cat5?  And the placement, are they free running in the plenum spaces, or are they in conduit (and I'd like to know about both the old wires and new wires there)?  Bascally, what variables changed beyond just moving from Cat5 to Cat6?

The other question I asked that I did get a response from you on goes heavily to dispelling rewobslc's and my theories about electrical noise....  Did the cable installers certify each of the runs?  (Their would be at least a printed page of testing results for each and every run if they did this, and those printouts should have been turned over to you at the end of the job.)

Like reswobslc polietly aluded to, the differance from getting a cheap beginner to do your wiring and paying more for an experienced professional to run and certify it may be only price at the lower speeds (10M & even 100M).  But at higher speeds (most 100M, 1G, and 10G) having these certified cables guarentees they'll be running right (and makes it well worth the cost versus trying to fix it later)

The company that runs our wiring is the company that has always run our network and telephone wiring.  No, the line was not certified because he did not have a CAT6 cable tester.  With this, I have to trust the installer.  You are correct when you said that the device on that line fails.  I believe, however, that I have switched the cables before, so that the wired is running off the top port and the wireless is running off the second port and it delivers the same problem.  

Ok, so instead of it being what ever is attached to that wire, it's what ever is connected to a particular port on the main switch?  That does change the whole ball of wax from wiring to the hardware on your main switch.  What kind of device (make and model) is this main switch and which port is it that is having devices fail on it?

Alright, now that we have moved away from what I originally thought, the wiring is terminated to a patch panel (do patch panels mess up?)  All of my wireless connections connect to a Netopia 4622 T1 VPN Router (which of course has the switch built into it).  It has an eight port switch, but I believe that I have even tried changing the port on the switch.  

In the remote possibility that the problem is not hardware and there is some regularity to the failure - check the system(s) that are losing their IP and, if applicable, check the (DHCP) Lease Expiration time (ipconfig/all).