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Currently we are having random time outs on our internet connection. I can confirm this by pinging google.com/yahoo.com and other sites and I see the connection work for about 10 - 12 requests, then it times out for two requests (which takes about 10 seconds). So our internet works for 10 seconds, then doesn't work for 10 seconds and it repeats all day. Its very annoying and frustrating.

Here is out current network setup:

We are currently using Optimum's High Speed Internet. The internet comes in from the coxail cable to Optimum's Arris Cable Modem. The cable modem's ethernet cable plugs into the WAN port of Optimum's Cisco Router (800 Series). The Cisco router provides us with 5 Static IP Addresses and the Cisco router has 5 ports on the back. Port 1 of the Cisco router is used for out VOIP Phones. Port Two links into the WAN of our Firewall (Linksys FR114P). Port 1 of our LinkSys firewall is plugged into the last port (24) of our Switch (TigerStack SMC6624M). All 12 of our computers are plugged into the switch as well from Port 1 - Port 12 (All computers in our building use Windows XP). We also have a wireless router (Linksys WRT54G) which is plugged into the firewall but it has been currently disconnected for 48 hours after a power cycle on all devices)

The firewall is our default gateway for every device. Its IP Address is 192.168.0.6, our Switch is 192.168.0.5. I tested the internet directly from the Cable Modem, as well as Optimum's Cisco Router, when its setup like this, there is no internet connection issue.

However when I am plugged into the Firewall or switch I do experience the issue. I have three command prompts open on 4 computers testing a connection to the internet (ping google.com) a connection to the firewall (ping 192.168.0.6) and a connection to the switch (ping 192.168.0.5). The firewall will time out the same time the internet (google.com ping) times out. The switch never times out.

Any idea what could be causing the issue? I have tried to reboot every device at once as well as individuality. Could a computer be causing the issue, could it be a network wide virus? Somone attacking us from outside the network? A faulty device.

If it matters at all I recently had to go to each machine and shut off the Remote Desktop feature because some users reported that someone tried to access the remote administrator account. After disabling RDP on all computers, one user just reported she got switched off of her account and was looking at the XP welcome screen, (a Switch not a Log Off), and then about 5 minutes later it happened again but this time actually logged her off. Could this be related?

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Could be a speed/duplex issue between the firewall and the switch or a spanning tree issue. Does your switch support spanning tree? –  resmon6 Feb 9 '12 at 16:43
    
There has never been anything wrong with the network for years and it started happening latly –  Taylor Silenzio Feb 9 '12 at 20:38
    
I started to take each device off of the network one-by-one untill I got to the route of the cause if its a computer causing the problem, however the issue stopped on its own. My boss is buying a new firewall incase the current one is malfunctioning, and its too old anyways –  Taylor Silenzio Feb 9 '12 at 20:40
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2 Answers 2

One possible issue I have encountered fairly often. Check all connections for a speed/duplex mismatch. While Auto/Auto should work, it does not always. Set each port to a static speed and duplex. Your ISP may need to make changes on their hardware. Have seen this with several ISPs but it often takes many calls to resolve.

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I forgot to mention that this just started to randomly happen after I have been here for over a year and a half. –  Taylor Silenzio Feb 9 '12 at 20:39
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up vote 0 down vote accepted

The issue resulted in a faulty device (the firewall to be exact). By replacing it, the issue has stopped altogether.

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