SEUL: Networking

[Erik Walthinsen <omega@omegacs.net>]

(this thread should move to seul-dev-admin)

> I have used 2 different pop's for quite some time.  In addition, a lot of
> users will use 2 or more accounts.  Their Internet account and their work
> account to connect to the LAN at the office.

There is a huge amount of work to be done in the networking field.  PPP 
connections are only the surface.  As far as multiple PPP links, I have 
much experience.  Not only do I have (custom) scripts to deal with them, 
but they're designed to handle multiple connections simultaneously.

Granted, that's just a little weird, but we at least need to pay very close 
attention to cases that aren't really as off-the-wall as you might think.

I have a laptop that moves around across three or four networks.  
Currently, I have to manually run ifconfig and route when I move outside my 
home network.  Software should be in place to deal with these things.

Some of the code needed to support roaming systems can be used in the 
installer, as well.  If someone has a machine with an ethernet card, but no 
clue what numbers to use, we should have a program that will use every 
means possible to attempt to determine this information.  It's rather easy, 
I think:

1) ifconfig eth0 0.0.0.0 netmask 0.0.0.0 broadcast 255.255.255.255
2) start listening (promisc mode) to the network
3) send out dhcp, bootp, rarp, RIP, etc. packets to the broadcast
4) as they come in, fill in all the information needed
5) if we don't have all the information we need, use the tcpdump to find it:
  a) subnets are almost *always* class C, guess otherwise
  b) single buck-shot flood ping of the entire subnet to find free addr
  c) listen for RIP announce packets, or check the arp and do a rarp, to 
     get router address
6) ifconfig eth0 addr

Many of those steps can be re-used in the roaming code, for network 
discovery.

What I'd like to see is SEUL developing administrative tools, likely in 
cooperation with projects like LinuxConf and COAS, that can manage *any* 
type of machine.  The range of configurations you'll find necessary in some 
home systems, especially now that home networking becoming more common, is 
quite similar to the range of configurations you'll find in full server 
environments.  Developing a single tool, in cooperation with groups like 
Linnet who want to make servers easier to run, should be one of our biggest 
goals.  The better system we can build for Linux in general, the better 
off SEUL will be.

Some have expressed concerns that we might end up spending too much time 
helping other groups, and not getting SEUL done.  That is not the case.  
Any help we give to other projects, in general, we will get back.  If we 
work with another group, say Linnet, to develop a more generic network 
configuration scheme, both groups will benefit immediately, and the 
community gets a single, stable, *strong* package instead of two 
incompatible ones that only work for a few cases.

TTYL,
    Omega

     Erik Walthinsen <omega@seul.org> - SEUL Project system architect
        __
       /  \                SEUL: Simple End-User Linux -
      |    | M E G A            Creating a Linux distribution
      _\  /_                         for the home or office user