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[skyeci]

Hi,

Wondered if anyone can perhaps explain what would cause the sync rate to be higher than the attainable. Currently my sync is 68 v 65 on the attainable. Historically my line has been the other way round - just interested to find out why this might happen and does this indicate some sort of problem somewhere?

Any advice appreciated.

thanks

[loonylion]

the SNR margin being below 6dB will cause this

[skyeci]

ah ok - cheers. This was a result of a resync when my line seemed to suffer from 21 ses last week but no idea why this was. Will DLM resync this again sometime or leave it as it is?

cheers

[loonylion]

if the SNR margin drops too far it will resync yes, but SNR can vary throughout the day so in all probability it will go back up and DLM will not see any need to take action unless you have significant errors.

[skyeci]

ok thank you. since the event its only just hanging on to 5.0-5.3  - I fear it may not go back up unless so other random event happens and I catch it.. -will leave it alone and see what happens

Oh well it resynced earlier by itself, loss of 4mb on the ds but the attainable is just over the  sync so maybe thats the trade off..

[Chrysalis]

the attainable is the modem estimating what the line will achieve on its target noise margin which is 6db for the FTTC product.

IF your current snrm is below the target then the attainable will be reported as lower than the existing speed, the majority of the time this will mean if you resync then the speed will drop down to close to the attainable speed, instances where it may not drop is if bitswapping has disabled tones, but those tones will come back on a resync.

[skyeci]

Ok cheers for that. Waiting on pcr engineer this week as the cabinet is not working properly. Had several port swaps on friday. Not one of the ports is giving out 80mb at the cab. I am inclined to ignore my line for now till the issue has hopefully been repaired. Network monitoring agreed with the findings so hopefully something will get sorted this week..

[NewtronStar]

Just a wee question how can a modem like the Billion 8800NL increase my sync rate and attainable rate by 4Mbps and the HG612 could not ?

[jid]

Just a wee question how can a modem like the Billion 8800NL increase my sync rate and attainable rate by 4Mbps and the HG612 could not ?

The 8800NL has a newer Broadcom chipset which does produce a higher sync rate.

When I had the 8800NL it did produce better attainable and higher snr for me, but I found it less stable. This was pre G-INP days. Other routers including the Zyxel and even the original TalkTalk Huawei Super Router included this more up to date chipset.

As for the tech reasons behind why it improves things I'm not sure but I would think it's a combination of improved hardware and software?

[NewtronStar]

Have seen three 8800NL on ebay and each selling lower than a HG612 seems odd why anyone would even contemplate purchasing the HG612 as the 8800NL is just better for sync on medium to long lines and with stats without having to go through the simple unlock process

Was even going to bid on one for the Wireless Distribution System it has as many routers don't have this even to-day

[skyeci]

Whilst the 8800nl is good I had to stop using it on my short eci line. Way to many errors. The zyxel has proved to be better and with a higher sync. I took note the engineer that came friday noted I was using a modem that meets sin498 etc..hard to blame  issues on the modem so had to investigate further..

[jid]

Was even going to bid on one for the Wireless Distribution System it has as many routers don't have this even to-day

Sounds interesting Newt, I didn't notice that on mine. What does it do?

[NewtronStar]

A Wireless Distribution System (WDS) is a system that enables the wireless interconnection of access points in an IEEE 802.11 network. It allows a wireless network to be expanded using multiple access points without the need for a wired backbone to link them, as is traditionally required.

http://www.billion.uk.com/esupport/index.php?/Knowledgebase/Article/View/51/3/how-to-connect-billion-devices-using-wds-mode

[Chrysalis]

Ok cheers for that. Waiting on pcr engineer this week as the cabinet is not working properly. Had several port swaps on friday. Not one of the ports is giving out 80mb at the cab. I am inclined to ignore my line for now till the issue has hopefully been repaired. Network monitoring agreed with the findings so hopefully something will get sorted this week..

I think that will happen if a line is banded, so the engineer needs to do a DLM reset before checking if 80mbit works.

Or is the DLM profile set on port's vs a line id?

[Chrysalis]

Whilst the 8800nl is good I had to stop using it on my short eci line. Way to many errors. The zyxel has proved to be better and with a higher sync. I took note the engineer that came friday noted I was using a modem that meets sin498 etc..hard to blame  issues on the modem so had to investigate further..

Yeah every line is different and as such what is good for one person sadly cannot mean its good for everyone.  For me the zyxel had a much higher error rate than the 8800nl. but that will be down to my line characteristics which the zyxel doesnt handle as well.