[clug] ADSL2+ speeds (Sakari Mattila)

Alex Satrapa grail at goldweb.com.au
Thu Feb 12 23:06:57 GMT 2009

On 13/02/2009, at 00:36 , smattila at tpg.com.au wrote:

> He changed the pair the telephone was using and now all is well.  
> There is big difference between
> pairs in  big cables. There is cross-talk between the pairs.

Not just cross-talk, but due to the way cable is terminated (eg: punch- 
blocks), you can end up with stray capacitance at the terminator  
simply due to the technician not checking that the ends of the were  
were trimmed at the punch block (rather than having another half an  
inch of copper radiating from the other side), then there's the  
possibility of wire being stretched as it's being manhandled into  
various pits and risers.

> I has been happy with "3"  1 - 6 GB per month 3G connection. Not  
> fast, about 2 Mb/s
> at best, in theory 3.6 Mb/s. Reliable, but depends on other 3G
> users. It is uncapped and about $ 110 per GB when over the limit.
> One trick to know and avoid: "3" RF-modem can make alternative
> GSM connection, uncapped.

I will never ever use "3" for this reason. If you drop off 3G  
connection, you are charged at normal data rates for GSM/GPRS.  
Actually, that should be "when" not "if".

Watching my girlfriend's supposed-3G connection through a provider  
whose name is not relevant, we'll be sitting at the dining room table  
with a 3G signal, and in the course of 10 minutes it will drop to GSM,  
back up to GPRS, then sometimes back up to 3G. Even worse, in the  
course of these channel/speed adjustments it will randomly get a new  
IP address. The best way to guarantee 3G connectivity is to keep hands  
off the computer (ie: do nothing for a while). The best way to  
guarantee that the connection drops back to GPRS or GSM is to start  
using the Internet.

3G wireless works fine for casual web browsing, but is unusable for  
anything that requires a session for longer than a few minutes, or  
more than a few dozen kbps speed.

This dodgey connectivity occurs in suburbs such as Holt and Isabella  
Plains. In some suburbs we have no connectivity at all (eg: certain  
streets in Dunlop). My experience has been that having no connectivity  
is easier to cope with than having dodgey 3G connectivity.

In the six months we've been using it, had we been using "3" we would  
have racked up a couple of hundred dollars in traffic charges.  
Thankfully we're not using "3".


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