Cable modem event log, strange entry!

mrk · 6 Apr 2008 at 10:52

Been away 3 days and today and yesterday noticed that the connection was running slicker than normal during the usual busy periods, even right now things are super fast (20MB) and my own website is now working full speed (1.7MB/sec) whereas before it would get 30k/sec (see previous thread).

I logged onto the modem and noticed this:

Code:

Fri Apr 04 01:30:49 2008 	Fri Apr 04 01:30:49 2008 	Information (7) 	New UCD in effect
Fri Apr 04 01:30:49 2008 	Fri Apr 04 01:30:49 2008 	Information (7) 	Starting on-the-fly UCD change.

Now I'm cool with this as whatever it is has sorted out slow browsing during busy times, just curious!

/happy 20MB customer!

TrX · 6 Apr 2008 at 12:54

Stands for upstream channel descriptor, which defines the symbol rate, bandwidth etc for the upstream connection. suggests maybe the upload was getting drenched at busy periods and they have increased the bandwidth.

This would have affected your speeds as if your system could not ACK each frame / group of frames. Then the remote system would not have sent the next frame, slowing the connection down.

mrk · 6 Apr 2008 at 13:13

So as I didn't understand a word of what you said I assume this is a good thing then?

Saying that though my upload speeds were never an issue, I could always upload at 90k/s !

TrX · 6 Apr 2008 at 14:36

mrk said:
So as I didn't understand a word of what you said I assume this is a good thing then?

Saying that though my upload speeds were never an issue, I could always upload at 90k/s !

seems to be a good thing if you now have much much faster download

All i'm saying is that a UCD change would only change upstream settings, and so if things are now better, it makes sense that it was a problem with your upstream.

The other possability is that the UCD just happens to have been a result of a larger range of settings changed at the cable head end.

either way, enjoy downloading at tasty speeds