[Cisco 857W] ADSL interface attenuation

Hi all,

I have at home a Cisco 857W router connected to an ADSL line. Very briefly, I need this equipment because I use the time-range based ACL's to manage Internet use at home. This i why I bought it instead of using any Netgers or Linksys box.

I am quite far from the DLSAM (local loop is 4.600 m long ...) and the attenuation of the loop (52 dB) is very close to the upper limit (53 dB).

Unfortunately, I'm having a problem with my cisco box.

When the cisco router is connected to the ADSL line, the attenuation raises to 56 dB (measured by the Cisco itself AND bye the DSLAM). When my ISP technician came home with its equipement and when its equipement is connected at exactly the same place than my router (just unplug the cable fom the router and plug it in the measuring equipement), the line attenuation is only 52 dB, confirmed by the DSLAM.

I have asked the company that sold me the 857W for a new one, as it seems to me that 4 dB of loss is rather high. Unfortnualtely, they seems to be reluctant to replace this equipment, and are only sending me newer firmware "just in case it solves the problem".

My question is : can anyone tell me wether 4 dB of loss is "normal" for a Cisco router connected to an ADSL line ? Do I have to insist until they send me another equipement ?

Reagrds,

PhC.

Reply to
Philippe
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See if there is a "dsl gain-setting" command. Don't know if it would help, but worth playing around with it, I guess.....

Reply to
John Agosta

Hi all,

thanks for all that.

I didn't know that Zyxel routers do have a "time range based ACL" mechanism. it's maybe worth trying.

I'm in France, and my provider is Orange. I'm running IOS 12.4(15)T4, wich seems to be the latest avalaible for my platform, according to informations I found on Cisco docs. My DSL firmware is 3.0.014; It's the release embedded with my IOS. I'v tried with 3.0.33, 3.0.43 and 4.0.15, but none of them do change anything to my problem (they seems to fix training problems with various DSLAM's).

I will try to play a bit with the dsl gain-seting rx-offset command, but I'm affraid it does't change anything. I'll keep you informed.

Regards,

PhC.

Reply to
Philippe

Thanks for the info regarding ISP.

Subsequent to my earlier post I noticed that the 4.x.x firmware was not applicable to the 8[57]7.

This along with your statements lead me to wonder if you actually managed to load the firmware since you do not mention that 4.0.x failed. You NEED to check with "sh dsl int atm 0".

" ..... Init FW: init_AMR-3.0.014_no_bist.bin Operation FW: AMR-3.0.014.bin FW Source: embedded FW Version: 3.0.14 ....."

This is what I see with the firmware integral to my IOS. If you succeed in loading the non integral firmware that output looks quite different.

I have not personally had any problems at all with firmware 3.x.x or later, only with some early 2.x.x.

One other thing worth looking at is to disconnect all other phone equipment on the premises. In the UK BT have a special diagnostic connection on the "Master socket" that connects directly to the outside - disconnecting ALL of the internal phone connections. Maybe you have something similar.

Finally - and sadly - over a quite a few 10s of DSL installations I came to the idea that there may well be something sub-standard (not sub-Standard necessarily) about the 8[57]7 routers. It did seem to be the case that cheap basic routers may well have worked better than the not so cheap and not so basic Cisco stuff. On most installations everything went well however there did seem to be quite a few reports (I was rarely on-site myself) that Brand-X is working and Cisco is not. We always managed eventually to get the Cisco to work, but the idea that there might be a deficiency became quite well formed.

I previously did a lot of 837s (several 10s) and did not notice the same effect with them.

Extra-finally:), you did not mention "dsl operating-mode" . I have found that fiddling with it was beneficial in some cases.

Good luck, please keep us in the loop.

Reply to
bod43

[...]

Hello,

I did check with sh dsl int atm 0, and yes, the 4.0.15 was loaded :) I will retry anyway, just to confirm, but I'm sure I did check and It was loaded :)

The Orange guy did verify the line attenuation all the way long from the DSLAM to my home. When the copper cable is cut just in my garage (exactly at the end of the local loop from wich Orange is responsible), attenuation is measured at 52 dB. When my "home installation" is reconnected, attenuation is still measured at 52 dB at the point where I usually connect my router. Sadly, when I connect my router, attenuation raises to 56 dB :(

I have had a lot of theses X-brand boxes during the last 10 years :) Some did work, some did'nt. I was especially worried by the Orange box (called Livebox in France, don't know in other countries), wich was a real crap in it's early versions. Not sure things are going better now, but I don't really want to try again ! As said in my first message, I use "intensively" the time-based ACL's (well, I have at least 2 rules and 2 time tanges :D), and the Cisco box is the only one I have found that meet my requirements.

I'm affraid you're right : not so cheap Cisco boxes seems to suffer a quality problem ...

I will insist to try to get a new one.

It was set to auto, I tried to force it in all the avalaible options, obviously only one worked :D

Thanks for all that, i'll keep you informed.

Philippe.

Reply to
Philippe

Firmware before update : Init FW: init_AMR-3.0.014_no_bist.bin Operation FW: AMR-3.0.014.bin FW Source: embedded FW Version: 3.0.14

Firmware after update and reload : Init FW: init_AMR-4.0.015.bin Operation FW: AMR-4.0.015.bin FW Source: external FW Version: 4.0.15

So, it works :)

Regards,

Philippe.

Reply to
Philippe

Phillipe this Firmware you mention is not available on the public FTP site yet - do you have a copy you can email or post on an FTP site?

Thanks

Reply to
peter.wonderboy

As mentioned the other day - ftp://ftp.cisco.com/pub/access/800/

Reply to
bod43

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