🚀 go-pugleaf

In article <1992Nov9.050242.16958@hawkmoon.mn.org> det@hawkmoon.mn.org (Derek Terveer) writes:
   Can I connect one machine on one network, say 183.100.1.1 to
   another machine on another network, say 142.49.1.18; or must both
   machines be one the same network?

Sure, no problem.  Just tell your PPP link about each end's IP
address.  None of the addresses are related to any other IP address in
either your address space of that of your peer.  Each IP interface is
independent of any others on the same machine, so it can use the same
address as some other interface, different addresses in the same
subnet, different addresses in the same network, or something you've
pulled out of thin air.

For example, our link to the world looks like
	du0: flags=0x51<UP,POINTOPOINT,RUNNING>
		inet 137.175.1.1 --> 38.146.20.1 netmask ffff0000 
The netmask is incidental and ignored.

[ Stuff Deleted ]

>Sure, no problem.  Just tell your PPP link about each end's IP
>address.  None of the addresses are related to any other IP address in
>either your address space of that of your peer.  Each IP interface is
>independent of any others on the same machine, so it can use the same
>address as some other interface, different addresses in the same
            ^^^^^^^^^^^^^^^^^^^^ ?

You mean if I have multiple PPP interfaces configured on a single machine
they can all have the same IP address ?!  Doesnt it get confused ?


Rob.
--
Rob Freyder                             Atlas Wireline a division of
____    ____     ____                   Western Atlas International Inc.
\   \  /   /\   /   /\                  A Litton / Dresser Company
 \   \/   /  \ /   /  \                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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   \/___/   \/___/  \___\               Voice     :  (713) 972-6678

In article <rob.721951004@hp11>,
    rob@hp11 (Rob Freyder) writes:

| You mean if I have multiple PPP interfaces configured on a single machine
| they can all have the same IP address ?!  Doesnt it get confused ?

Curiously enough, it works - I've done it.  As is pointed out in a README
in one of the implementations, when IP detects a Point-to-Point link
(marked as POINTOPOINT) it ignores the local address, and just looks at
the destination address.  Very useful, and no need to waste IP addresses.

-- 
Dave Horsfall (VK2KFU)         VK2KFU @ VK2RWI.NSW.AUS.OC
dave@esi.COM.AU                ...munnari!esi.COM.AU!dave
           Disclaimer: "Me, speak for us?"

In article <BOB.92Nov10094722@volitans.MorningStar.Com>, bob@MorningStar.Com (Bob Sutterfield) writes:
B.Sutterfield|>  In article <1992Nov9.050242.16958@hawkmoon.mn.org>\
B.Sutterfield|>  det@hawkmoon.mn.org (Derek Terveer) writes:
B.Sutterfield|>  Can I connect one machine on one network, say 183.100.1.1 to
B.Sutterfield|>  another machine on another network, say 142.49.1.18; or must\
B.Sutterfield|>  both
B.Sutterfield|>  machines be one the same network?

B.Sutterfield|>  Sure, no problem. Just tell your PPP link about each end's IP
B.Sutterfield|>  address. None of the addresses are related to any other IP\
B.Sutterfield|>  address in
B.Sutterfield|>  either your address space of that of your peer. Each IP\
B.Sutterfield|>  interface is
B.Sutterfield|>  independent of any others on the same machine, so it can use\
B.Sutterfield|>  the same
B.Sutterfield|>  address as some other interface, different addresses in the\
B.Sutterfield|>  same
B.Sutterfield|>  subnet, different addresses in the same network, or something\
B.Sutterfield|>  you've
B.Sutterfield|>  pulled out of thin air.

B.Sutterfield|>  For example, our link to the world looks like
B.Sutterfield|>  du0: flags=0x51<UP,POINTOPOINT,RUNNING>
B.Sutterfield|>  inet 137.175.1.1 --> 38.146.20.1 netmask ffff0000
B.Sutterfield|>  The netmask is incidental and ignored.


Bob - Except when you are routing packets to one via the other from the Internet
	and vice versa. You need to get a NIC registered IP address. Also, if
	these point to point links are hooking up networks which are subnetted
	then you will need proper masks for routing packets; correct?

-- 

				-- Arif Diwan (adiwan@bbn.com)
						617/873-6274

In article <1992Nov19.151251@bbn.com> adiwan@bbn.com (Arif Diwan) writes:
      In article <1992Nov9.050242.16958@hawkmoon.mn.org> det@hawkmoon.mn.org (Derek Terveer) writes:
         Can I connect one machine on one network, say 183.100.1.1 to
         another machine on another network, say 142.49.1.18; or must
         both machines be one the same network?

      Each ... IP interface can use ... some [address] you've pulled
      out of thin air.
      
   Except when you are routing packets to one via the other from the
   Internet and vice versa. You need to get a NIC registered IP
   address.

Of course.  I was trying to make the point that the IP addresses of
two different interfaces on the same machine (at least machines
running BSD-like UNIX variants) are totally unrelated.

      The netmask is incidental and ignored.

   Also, if these point to point links are hooking up networks which
   are subnetted then you will need proper masks for routing packets;
   correct?

No, the original question mentioned connecting different network
numbers, and subnet masks are a private matter within each Autonomous
System.  That's the whole point of subnetting.

For example, I suspect that bbn.com probably uses 8-bit subnets within
128.89, but (a) I can't easily tell, (b) it would be too much for all
the routers in the world to keep track of all the subnet masks inside
all the world's ASs, and (c) I don't care.  The rest of the world
shuffles all packets for 128.89.0.0 toward your NEARnet gateway, and
we let your internal routers figure it out from there.