[Tutor] OT: need computer advice from wise Tutors

Alan Gauld alan.gauld at btinternet.com
Tue Jun 29 17:32:21 CEST 2010

"Walter Prins" <wprins at gmail.com> wrote

> a) I sometimes use Gmail while we visit folks in South Africa who 
> are still
> on 56k dial-up.  Initial log-in can be a bit slow, but generally 
> you'd be
> surprised at how efficient/quick it is w.r.t bandwidth.

To be fair to Google, GMail is one of the best implemented web mail
systems around. If you must use web mail then I'd go with Gmail
over Yahoo for example.

> the amount of mail I receive on a daily basis, using a conventional
> "download then read" client on a 56k dial up link would be totally
> impractical for me,

I've used a desktop client for the last 25 years, even over a 1200 
dialup modem. Because it downloads in the background you rarely notice
the delays. My volumes have increased in the 30 years but only from
about 30-200 mails a day, my bandwidth OTOH has increased by
much more! :-).

> b) Gmail does a lot of in-browser caching,

Sure, as I say GMail is one of the best but the cache times out and if 
read older mail it does download it afresh. I regularly reference mail
from a year or more ago.

> c) As the web matures the trend towards web-applications being able 
> to store
> data locally and run off-line should increase, further improving 
> bandwidth

Absolutely, but that requires the programmers to intimately understand
the impact of their internet usage. Which is the point being made by
Steven and myself. Its not a dig at Web mail per se, its the fact that
as programmers we need to understand exacvtly what is going on
over the network and its potential impact - and not just on the 
user but those users potentially sharing the network.

> c) Stating the obvious but you can turn downloading of images off by 
> default
> in your browser, which will of course further reduce the actual 
> bandwidth

I used to do that when I had Mosaic running over 9600 baud, but after
I got to 56K I turned them back on - especially when web designers 
sending text as graphics (to get fancy fonts) and did so without using 
alt tags!

> d) Using Gmail means you don't waste bandwidth unneccesarily 
> downloading
> mails with big attachments (PDF files, Word files) unless you 
> actually want

Most desktop clients can either only download headers and fetch the 
on demand, or download headers and body but leave attachments till 
or download everything. On my mobile phone I go headers only, on my 
PC I get everything and on my home PC I get headers and text.

> e) Actually having access to your email from places you wouldn't 
> normally
> have access to it (on holiday, at conference) is a benefit you don't
> neccesarily have with a conventional client.

No, and this is where webmail is genuinely useful.
I have 6 email accounts and all of them have a webmail inteface but I 
all of them into my desktop client. But if I am on holiday and don't 
have my
PC then I use webmail to keep abreast of things. I'm not against Web 
I just recognise that its not a network efficient way to read email.

> I absolutely agree about programmers having to be aware of the 
> bandwidth
> costs involved with every operation they do, as bandwidth isn't 
> free.
> However, the internet is after all, a network, and the argumentation
> ostensibly against web based services (especially potentially 
> relatively low
> bandwidth ones like gmail) on the basis that they consume network 
> bandwidth
> per-se, seemed a little OTT to me.  YMMV.

I don't think anyone is arguing against these services. Cloud 
computing is
almost certainly the future. But as programmers - and this is a 
list - we need to be aware of and understand how apps use the network
and how we can minimise the adverse impacts.

And as responsible internet users we should recognise the negative
impacts our usage habits can have on our neighbours, in much the
same way as drivers need to recognise the impact of bad driving
on other road users. Email is, as someone pointed out a relativel 
small consumer
of bandwidth, much worse would be somebody leaving a streaming video
source on auto repeat! But having said that the latest figures still 
text services as about 50% of all internet traffic, so every little 

Alan Gauld
Author of the Learn to Program web site

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