configuring a network with various alternative routes

Hello,

I am trying to figure out how to connect two computers, A and B, so that they
can connect to each other using TCP and UDP, and so that I can tell one computer
to send some data over their wireless 802.11 connection, different data over the gigabit lan
connection, and still other data over a satellite connection. The computers dual boot XP and linux
and I need this to work in any OS mix.

For starters, I suppose each computer could have several IP addresses, one for each type of connection, so that connecting with
sockets on a particular kind of connection reduces to knowing which IP address routes over each? For this to work I need a router
that I can configure somehow? Not sure.


Thanks in advance for your help!
-J

In news:(E-Mail Removed) m,
nospam <(E-Mail Removed)> typed:

> I am trying to figure out how to connect two computers, A and B,
> so that they can connect to each other using TCP and UDP, and
> so that I can tell one computer to send some data over their
> wireless 802.11 connection, different data over the gigabit lan
> connection, and still other data over a satellite connection

Why would you want to do that?

> The computers dual boot XP and linux and I need this to
> work in any OS mix.

Simplification is your friend.

> For starters, I suppose each computer could have several IP
> addresses, one for each type of connection, so that connecting with
> sockets on a particular kind of connection reduces to knowing which
> IP address routes over each? For this to work I need a router that I
> can configure somehow? Not sure.

Obviously, you're not even sure what you want to do, or why.

>> I am trying to figure out how to connect two computers, A and B,
>> so that they can connect to each other using TCP and UDP, and
>> so that I can tell one computer to send some data over their
>> wireless 802.11 connection, different data over the gigabit lan
>> connection, and still other data over a satellite connection
>
> Why would you want to do that?
OK. I'll bite... in spite of the obvious provocation and in case
the SNR in this group is actually better than your reply.

The different types of connections each have unique characteristics:
bandwidth, reliability, availability, etc.

To ensure that a large message is delivered in timely fashion, using a
bigger pipe is best. For a critical message, using wireless may not be
a good choice.

The ability to choose which data goes out over which type of connection allows
you to prioritize the various kinds of data and control bandwidth usage.


>> For starters, I suppose each computer could have several IP
>> addresses, one for each type of connection, so that connecting with
>> sockets on a particular kind of connection reduces to knowing which
>> IP address routes over each? For this to work I need a router that I
>> can configure somehow? Not sure.

Anyone with helpful response?

Thanks,
J

On May 8, 4:06*pm, nospam <nos...@spamnot.net> wrote:

> OK. I'll bite... in spite of the obvious provocation and in case
> the SNR in this group is actually better than your reply.
>
> The different types of connections each have unique characteristics:
> bandwidth, reliability, availability, etc.
>
> To ensure that a large message is delivered in timely fashion, using a
> bigger pipe is best. For a critical message, using wireless may not be
> a good choice.

You may think this is the best way to do things, but the collective
wisdom is against it. The collective wisdom would be:

1) Use a routing protocol to see which links work and which don't.

2) Send all traffic over the highest-capacity link that is currently
known to work. (Perhaps sharing the load if there are multiple equally-
good or almost-equally-good links.)

3) If a link fails, detect this by the routing protocol packets not
going through.

> The ability to choose which data goes out over which type of connection
> allows
> you to prioritize the various kinds of data and control bandwidth usage.

Perhaps, but not in a way that is usually useful. It is typically more
logical to control bandwidth usage and prioritize at the link itself.
After all, controlling bandwidth usage and prioritizing data are
sensible things to do even if you only have a single working link --
in fact, especially so.

> >> For starters, I suppose each computer could have several IP
> >> addresses, one for each type of connection, so that connecting with
> >> sockets on a particular kind of connection reduces to knowing which
> >> IP address routes over each? For this to work I need a router that I
> >> can configure somehow? Not sure.

This is a common paradigm. It's not always required, but it's
sometimes useful. You assign an IP address to each end of each link.
Often, you also assign an IP address to the host itself. Your routing
protocol then routes packets usually addressed to the "host itself" IP
address through the link endpoint IP addresses. You can still use the
link endpoint IP addresses if you want, but they may or may not make
traffic take that link (since the other links reach that IP address
too).

> Anyone with helpful response?

It's hard to help you since you don't seem to know what you want to
do.

DS

On Thu, 8 May 2008 18:06:07 -0700 (PDT), David Schwartz
<(E-Mail Removed)> wrote:

>You may think this is the best way to do things, but the collective
>wisdom is against it. The collective wisdom would be:

bs

Read http://lartc.org/howto/lartc.rpdb.html for information about
Policy Routing to see if that is appropriate for your situation.

--
buck