Hello folks,

We've got a fairly new T1 (about a month and a half old) that we've been experiencing problems with since a few days after we moved it fully into production. I'm going to start with a background on the problems we've been experiencing leading up to my use of ping plotter as an investigative tool just to gather more information.

About 4 days after we moved our entire office from our old T1 line to our new one, the T1 went into an UP/DOWN state. Our carrier (AT&T) insisted the problem was on our end. So, we changed the router out, changed the cabling out, we confirmed our configuration against the data sheet AT&T sent us and had the manufacturers of our router confirm our settings. Everything looks good at this point. About a week later the same problem happened again, and again the next week. I've noticed in our router a high number of CRC errors and some other errors such as line and path code violation errors. At one point before the T1 went down, the CRC error count was at ~230,000 for about a week of uptime. Usually before it goes out the T1 slows to a crawl and then goes into an UP/DOWN state (protocol is down). So, a month and a half later we have gotten no where with AT&T and getting them to figure out what's wrong. Today I ran across ping plotter and decided to give it a run just to see how traffic was flowing (our connection has been running pretty slow the past 2 days). I ran ping plotter against www.google.com and I'm seeing one hop that is experiencing super high packet loss. I read that ICMP may be dropped, limited, throttled or whatever by some routers so I switch to TCP and HTTP and see the same exact results. I'm wondering if what I'm seeing is really a problem and if it could be related to the high CRC error count we're seeing on our T1 line. Here is a screen capture after about an hour of pingplotter running:

http://itdevel.net/~jp/www.google.com.png

If anyone could take a look and confirm if this is or isn't any kind of issue we should be concerned about I'd appreciate it very much. As it stands now, we're running in the dark trying to figure out the root cause of our new T1 woes since AT&T keeps taking us in circles.

Thanks

After further reading, I've deemed the packet loss I was seeing to be a non-issue and more than likely not related to our CRC errors and slow traffic. Sorry if I've wasted anyone's time with this post.