Where's the "Far End" of a DSL circuit?

My Actiontec GT701 is a bit short on diagnostic and error reporting, but when I looked at it this AM, I see the error counters are astronomical, and one of them is climbing rapidly during a file transfer.

I see these counters right now:

Near End CRC Errors (I/F) 575/0 Far End CRC ... 10759/0 Near End RS FEC 39168/0 Far End RS FEC 54469597/0

and the "Far End RS FEC" counter is climbing rapidly (55089354 by the time I typed in this line) while the others aren't changing at all.

I now see that the "Far End RS FEC" counter continues to climb even when there's no data traffic.

So, where's the "far end", and what's likely causing the errors?

BTW, I was sold a 7Mb line from Qwest, I'm trained at 6112/896 right now and file transfer is still running at about 5-6Mb/sec from a capable site.

Reply to
Bert Hyman
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At first I thought you had a problem. Until I read the part about having a

7MB line and getting solid 5-6MB transfers. Considering that, I would consider these errors "normal". The modem is doing its best on your line to achieve the highest transfer. You are trained at a speed that is probably slightly above optimal. But I have found that this is better than below optimal where you have no chance of ever achieving optimal transfer.

About being "sold a 7MB line". Qwest sells services "up to" certain speeds (like 7MB). Getting 5-6MB is certainly in line with what you were sold. There are a lot of factors that determine whether or not your line can actually achieve 7MB.

They won't even sell me a plan over 1.5M/856K.

-Frank

Reply to
Frankster

If there really is a "problem", I believe it is that the modem is training at a higher speed than it is capable of delivering without significant errors. Do you have the latest version of firmware in your Actiontec? Not that the latest is always the best in this regard, but it is something to try. I have been through this with the Actiontec before. There is no way to force it to train at any given speed. It handles the negotiations automatically during connection. However, different versions of firmware have different amounts of aggressiveness.

Check your train speed on the WAN Status page. You will probably train at different speeds occasionally after a restart. I'll bet you find that you get more errors when trained at the higher speeds.

Having said all that.... the errors are USUALLY on the near end. Far end errors indicate errors on the carriers end of the connection. On lower speed connections (like my 1.5M) the carriers end errors are normally almost zero. But on a high speed connection like yours, I would not be surprised if the carriers equipment isn't quite up to the task of 7MB either. Remember, this is specific to your particular C.O., not the carrier overall in all its locations.

Just my take.

-Frank

Reply to
Frankster

Bert,

Here's an explanation:

"Near End CRC Errors (I/F), Far End CRC Errors (I/F) - Displays the number of interleaved (I) and fast path (F) cell errors occurring on the DSL line. Near end errors occur on the DSL network side; far end errors originate from the DSL modem. These numbers can be used to diagnose network problems, such as slow response times."

I've wondered what they mean as well, since I have a couple of clients and friends using the Actiontec. I found the explanation here:

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It appears to be an older version of the Actiontec wireless DSL modem; the version up on Qwest's site doesn't have the info in it anymore.

Now I need to track down what Local and Remote counters really mean on my Cisco 678. I'm getting the feeling I should think of it from the phone company's perspective, where Local is the central office, and Remote is my modem.

Hope this helps, Bob.

Reply to
Bob

Still, the connect time will matter. This many errors in 1 hour is a lot different than this many errors in 6 months.

Also, I have read that Actiontec modems had a problem where they quadrupled the number of errors (or maybe times 10, I can't remember). Some SW upgrade was meant to fix that. Don't know if it did.

-Frank

Reply to
Frankster

I agree that my line is ->probably doing as well as it can, but the error counts aren't normal. While I'll usually see counts in the thousands after the box has been up for a few a day or so (I usually turn it off overnight but sometimes forget), counts in the tens-of-millions are unusual.

The fact that the count continued to climb rapidly even when there was no data traffic was also interesting.

Resetting the box caused the error counters to return to their "normal" behavior, so I still don't know if it's a line problem or a router problem, or if the problem is on my end or at the CO.

Reply to
Bert Hyman

Well, that's what started this whole thing:

Near End CRC Errors (I/F) 575/0 Far End CRC ... 10759/0 Near End RS FEC 39168/0 Far End RS FEC 54469597/0

Far End RS errors in the tens-of-millions and rising.

Reply to
Bert Hyman

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