[clug] ADSL2+ speeds (Sakari Mattila)

Ian darkstarsword at gmail.com
Sun Feb 15 14:04:03 GMT 2009


<snip>

> 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.

I'm with Optus using my Nokia N95 as a bluetooth/USB modem (hint for
anyone else following along at home: The SMS Optus sends with the
settings for the phone they have detected you are using contain an
incorrect wrong APN). I found that when it was set to dual mode it
would tend to favour dropping back to GSM, but by simply setting it to
only use UMTS (3G) this problem vanishes - you might want to play
around with the settings for your modem to see if you can do the same.

The moment I start transferring data for more than 0.5 seconds or so
the phone indicates that it has moved to HSDPA/3.5G - I assume it does
this to conserve it's power when it's not actually transferring
anything, the IP address does not change when this occurs. Having said
that, the IP does change quite often - usually when the bluetooth link
between the phone and the computer or Internet Tablet drops out. When
using it over USB this is practically a non issue for me, though I
dare-say that will depend on your coverage.

In the event that I am outside Optus' 3G coverage I simply set the
phone to use dual mode if I'm in an optimistic mood, or GSM if I know
3G is futile and want to conserve the battery life.

As a side note, I have noticed that I am able to use the Internet
connection on the phone at the same time it's acting as a modem. If I
do so it will stay at the slower 3G, but both devices get unique IP
addresses (Internet addressable too - thanks Optus).

Cheers,
-Ian
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