Hi,
I recently contacted VM broadband tech support having suffered a drop-off in BB performance (feels like a latency/packet loss prob). I included the following status info from my cable modem and suggested the cause could be a low d/s SNR:
D/S status page:
Downstream Lock : Locked
Downstream Frequency : 402750000 Hz
Downstream Modulation : QAM256
Downstream Interleave Depth : 32
Downstream Receive Power Level : -4.0 dBmV
Downstream SNR : 25.1 dB
U/S status page:
Upstream Channel ID : 1
Upstream Transmit Power Level : 49.0 dBmV
Upstream Symbol Rate : 2560 Ksym/sec
Upstream Frequency : 25800000 Hz
Upstream Mini-Slot Size : 2
I received a reply saying "The minimum SNR varies in different regions. In your region it is between 25dbmv - 33dbmv for QAM256". The sticky post on the topic in this forum says the recommended SNR is 33 for the Langley platform. Should I regard 25.1dB as acceptable and unlikely to be the cause of my problems?
Also provided the following ping info:
Pinging
www.bbc.net.uk [212.58.253.70] with 32 bytes of data:
Ping statistics for 212.58.253.70:
Packets: Sent = 57, Received = 54, Lost = 3 (5% loss),
Approximate round trip times in milli-seconds:
Minimum = 44ms, Maximum = 2749ms, Average = 252ms
And 3 tracerts similar to this:
Tracing route to
www.bbc.net.uk [212.58.251.195]
over a maximum of 30 hops:
1 1 ms <1 ms <1 ms xxx
2 6 ms 23 ms 26 ms 10.247.28.1
3 39 ms 40 ms 38 ms 80.4.118.25
4 40 ms 40 ms 41 ms 62.252.64.85
5 40 ms 41 ms 39 ms 213.107.47.102
6 42 ms 42 ms 39 ms 213.105.175.153
7 52 ms * 41 ms 62.253.185.117
8 45 ms 45 ms 43 ms 62.253.185.98
9 45 ms 44 ms 45 ms 62.253.185.78
10 45 ms 49 ms 45 ms 212.58.238.189
11 * 45 ms 48 ms 212.58.238.149
12 46 ms 45 ms 49 ms 212.58.239.62
13 43 ms 44 ms 44 ms 212.58.251.195
Still following up with support, but wondered if anyone can comment on the SNR question and how reasonable that ping and tracert info is.
Thanks for any advice!
Nick
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