[MLB-WIRELESS] East Timor

[Tony Langdon, VK3JED]

At 04:09 PM 6/3/2007, Rick wrote:
>im sure theres something that will do load sharing between 2 dial up
>connections that should allow a few people to get on web browsing happerly

Well, I shared dialup for an office LAN back in the mid 90's.  We 
were running 33.6kbps (later 56k when that become available), and the 
router was an old 486 running pppd and ipfwadm (yes, a 2.0.x 
kernel!).  It worked, though often rather slowly when a few dozen 
users hit it.  Mind you, when we approached the ISP for an upgrade to 
the connection speed at a later stage, they were somewhat amazed at 
the amount of data we managed to suck down a dialup... think it was 
something like 3-6 gig/month. :)

If I was to do it now (i.e. the East Timor situation), I'd set it up 
in a fairly similar manner, but with a modern distro.  The tweaks I'd make are:

1.  Limit the MTU to 576 bytes for the PPP connection.

2.  Setup traffic shaping so that the limited bandwidth is shared 
equally between users, and important traffic (e.g. SSH, if you need 
to administer it remotely) gets priority.  The bandwidth limits would 
have to be determined experimentally, according to the actual 
connection speeds achieved.

3.  Setup a Squid proxy and ensure all users use this proxy (whether 
that be by using a transparent proxy, or simply blocking port 80, so 
it can't be bypassed).  Extremely popular downloads could be mirrored 
during the night, or brought in via sneakernet, if someone is 
travelling regularly to a place with better connectivity (good 
approach for Linux distros and other large files that change 
occasionally).  it's hard to beat the bandwidth of a suitcase full of 
DVDs ;)  Basically, take every step to minimise redundant traffic 
across the dialup.  From experience, Squid can make a huge difference 
on dialup.

73 de VK3JED
http://vkradio.com