Connection problems in Reading

[agatward]

Hi,

I am experiencing intermittent connection drops - has been happening perhaps once per day for the last week or so but it did it a lot today. The drop times coincide with some interesting log entries and the modem reinitialising it's MAC. Does this indicate a faulty modem or a faulty cable?

Sample of log entries follows:

Mon Aug 21 15:18:22 2006
Mon Aug 21 15:18:22 2006 1 Critical(3) 82000700 Unicast Ranging Received Abort Response - Re- initializing MAC
Mon Aug 21 15:18:05 2006
Mon Aug 21 15:18:05 2006 2 Critical(3) 82000200 No Ranging Response received - T3 time-out
Mon Aug 21 15:18:02 2006
Mon Aug 21 15:18:02 2006 1 Critical(3) 82000700 Unicast Ranging Received Abort Response - Re- initializing MAC
Mon Aug 21 15:17:44 2006
Mon Aug 21 15:17:44 2006 4 Critical(3) 82000200 No Ranging Response received - T3 time-out
Mon Aug 21 15:17:39 2006
Mon Aug 21 15:17:39 2006 1 Critical(3) 82000700 Unicast Ranging Received Abort Response - Re- initializing MAC
Mon Aug 21 15:17:21 2006
Mon Aug 21 15:17:21 2006 4 Critical(3) 82000200 No Ranging Response received - T3 time-out
Mon Aug 21 15:17:17 2006
Mon Aug 21 15:17:17 2006 1 Critical(3) 82000700 Unicast Ranging Received Abort Response - Re- initializing MAC
Mon Aug 21 15:16:59 2006
Mon Aug 21 15:16:59 2006 4 Critical(3) 82000200 No Ranging Response received - T3 time-out
Other information which may be useful to those in the know:


Downstream Receive Power Level: 2.3dBmV
Downstream SNR: 34.8dB
Upstream Power Level: 60.0 dBmV

To me the upstream seems a bit high, I'm pretty sure it used to run about 52.0. The modem is using QPSK upstream and QAM64 downstream, on a 10Mbit service.

The modem is an NTL:250 one.

I'd really like to avoid having to phone the help desk as they're useless at the best of times and they also can't handle that my modem is plugged into a hardware firewall.

Thanks in advance,

Andy.

[homealone]

according to this

http://www.cableforum.co.uk/board/showthread.php?t=26006

your upstream power is, indeed, marginally high - unfortunately only an engineer visit can sort that out, afaik, sorry ...

[agatward]

Have been keeping an eye on this for the past week or so. Downstream SNR is averaging 34.8dB, received power averages 1.6dBmV. Transmit power is averaging 61.0dBmV. I'm also averaging between 3 and 10 drop-outs per day but the modem never reboots (or at least the Ethernet link is not reported as dropping by my firewall).

Definitely think I need an engineer visit... However I really don't want to have to go through tech support as I have an enterprise-grade hardware firewall (Juniper Netscreen 5GT) and they always wish to blame that. I have tried reconnecting the coax cable at both ends, and have also tried giving the centre conductor a light cleaning.

So... are any NTL techs on here willing to sort me out an engineer visit or can recommend how I get through the hoops that support wish me to jump through without completely dismantling my network?

Thanks in advance,

Andy.