Level 1: Cadet

Cable Latency and Speeds

I've had telstra 30 mb/s cable for a few months now, im in a new apartment block in Rhodes. Every few days in the afternoon i get shocking pings and download speeds. I am aware that cable performance can be effected by the amount of people in the area but i didnt think it could be so bad.


Its not uncommon for my download speeds to drop to around 29 kBps and stay there for a fair chunk of the night. On top of that im pinging google.com.au and getting a significant amount of responses in the 250+ range, some as high as 500ms to 900 m, in fact finding something thats 70ms and under is on the rarer side on the bad nights.


It makes doing anything on the internet impossible, videos dont load, games lag like crazy. I've only used ADSL before this so i dont know if the following SNR values and whatnot are at acceptable levels. Are these effects a constant thing for telstra cable connections in large apartment blocks?





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Level 20: Director

Re: Cable Latency and Speeds

In reply: @Helios504


What model modem do you have? (CG3100 or CG3100D-2)


Your SNR levels are low, thus you have noise on the HFC, so let me ask the following:


a. Do you have Foxtel? If so, does it have a high pass filter/amp?

b. Do you have a connected attenuator on your Cable modem coax? If so, remove it!

c. Are you running the modem in Bridged or Router mode?


Looking forward to your reply Smiley Happy

Level 1: Cadet

Re: Cable Latency and Speeds

Thanks for the reply Smiley Happy


a - nope no foxtel

b - as far as im aware i do not have an attenuator connected (the modem is plugged directly into the wall)

c -  the modem is running purely in Router mode


I have the CG3100D-2.


I find it strange that there would be low SNR values in such a new apartment (its about 6 months old/some floors in construction still) Smiley Sad

Level 20: Director

Re: Cable Latency and Speeds

In reply: @Helios504


If you connect your PC's directly to the modem separately, post the results of a proper speedtest of all machines.


Can you also post results of a wftrace when you find everything great and again when horrible (to google is fine).


SNR levels only means noise, and this does not necessarily mean that noise is due to a new premise, it could be that the tap connector is old and leaking some noise in on the coax, or there is a transformer that is leaking copious amounts of EMF into the coax, it has nothing to do with the actual install date of the coax.


Have you had a Tech out to look at the issue recently?


Do you have a connected ADSL modem to act as a router? If so remove it!


Do you have a connected separate router?


Is the Ethernet cables in good shape? If so, have you swapped them out?


Do you have the latest OEM drives for your NIC?


Keep us updated Smiley Happy

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