cancel
Showing results for 
Search instead for 
Did you mean: 

Draytek Vigor Router & Uncorrected Blocks

N/A

Draytek Vigor Router & Uncorrected Blocks

I've got a Draytek Vigor 2600 router, and I'm looking at the ADSL stats to see if it shows errors, but the only thing I can see is something called "uncorrected blocks".

Here is what is says;

TX Blocks RX Blocks Corrected Blocks Uncorrected Blocks
42656214 42656007 0 7659


Is this good or bad or just normal? and is this even what I should be looking for?
8 REPLIES
Lorian
Grafter
Posts: 699
Registered: 31-07-2007

Draytek Vigor Router & Uncorrected Blocks

How long does the router say it's been up, and what speed, attenuation and SNR is your line?
N/A

Vigor 2600

Hi,

I have a Vigor 2600 and had exactly the same question as you!

What I determined was, the Vigor uncorrectable blocks are what other router manufacturers call "CRC ERRORS".

The ADSL data stream is always subject to errors, so there are a number of errror correction schems to recover the data if possible.

The error corrections are: Forward Error Corrections (FEC), Cyclic Redundancy Check (CRC), and Header Error Check (HEC)

I cannot remember the correction schemes in detail, suffice it to say, some errors are corrected on the fly, by using the redundant information carried in the stream. (or the CRC byte)

However if the error burst exceeds the capability of the CRC checker to correct the error burst, then a uncorrectable error is logged. Its still not the end of the world, 'cause that packet will get nacked and retransmitted. The problem arises when the uncorrectable errors form a large percentage of your total packets transmitted. If they are a small percentage then there is no need to worry.

I used to get 500 uncorrectables a week on 5 GB data, with the Vigor - It never used to bother me

However, recenly I changed my 2600 router for a Billion 7402VGO router, ( a new one that also does ADSL2+ ( not here yet!)). I never got more than 2 uncorrectable errors ever... They always occurred on connection at startup.

The Lower your signal to noise Margin is the more likely it is you will get uncorrectable errors.

I have just been DSLMAXED (on the 2nd May). My SNR margin has dropped from 29 to 7 dbs, and the uncorrectable errors have gone from 2 to 600 in two days! ( I am downloading RR64 RC1 (2.5 GB during this though!) My router is synced up at a rock solid 8128 since the MAXDSL

Still 600 retries in 2.5 Gbytes of data, I am still not worried.

The time to worry is if you have a good SNR margin AND you get loads of CRC errors, in this case you want to do all the good things to reduce impulse noise on the ADSL feed from the master socket to your router. There are lots of articles on how to do this.

I found the best way was to rip out ALL my extension wiring. I ran ONE Cat5 twisted pair from the master socket to a filtered dual ADSL / phone faceplate by the router. This faceplate reintroduced the ring circuit only for the only phone I have plugged in, (a 4 extension DECT whose base station is plugged into the filtered output.)

This lifted my SNR ratio from 19 to 29 dbs !!!!

regards

Patrick
N/A

Draytek Vigor Router & Uncorrected Blocks

I rebooted the router earlier today, so it's only been up for 4 hours 4 minutes, but my ADSL connection has been up for 4 hours and 3 minutes, and I've been downloading constantly at 250k for the last 1 hour 15 minutes without any issues.

Mode--------State------------Up Speed------Down Speed--SNRMargin---Loop Att.
G.DMT ------SHOWTIME---448000---------8128000-------7.0---------------34.5
N/A

Draytek Vigor Router & Uncorrected Blocks

This after downloading about 1.2gb of data

TX Blocks RX Blocks Corrected Blocks Uncorrected Blocks
61424628

RX Blocks
61424283

Corrected Blocks
0

Uncorrected Blocks
12075

So the uncorrected blocks is 0.02% of the RX Blocks, so I'm assuming that theres no need to be worried.
Lorian
Grafter
Posts: 699
Registered: 31-07-2007

Draytek Vigor Router & Uncorrected Blocks

Correct.

You might also like to read this similar thread: :edit: LOL I see you already have

http://www.draytek.co.uk/forum/viewtopic.php?t=7185

You'll need to setup and account to view it if you don't have one already.

One interesting fact from that thread is "(if they) exceed 5000 uncorrected blocks in 7 secs or less it will trip the threshold (to re-train the router)"
MysteryFCM
Grafter
Posts: 528
Registered: 30-08-2007

Draytek Vigor Router & Uncorrected Blocks

We've got a Draytek Vigor at my office and I've got to admit, I've never come accross a router that appears to make the admin area deliberately difficult to get to, work with, and configure :? .... lovin my Netgear, hehe

Note: I know my response is OT and unnecessary - just never saw a chance to vent about this router before ..... Shockedops:
N/A

Draytek Vigor Router & Uncorrected Blocks

Yeh the best routers are always difficult to setup, just look at cisco, their web interface is terrible, they are best configured via the COM connection. However cisco is probably the best brand you can get.

I think drayteks are really meant to be configured using telnet.

We have a couple of cisco ADSL routers at work which cost over £200, but the web interface it horrible.

Drayteks tend to be used more in a business environment and not at home, which explains why they dont have a great interface.
Lorian
Grafter
Posts: 699
Registered: 31-07-2007

Draytek Vigor Router & Uncorrected Blocks

The web admin interface on my 2800VG is very good.