Subject: RE: "ROUTERS" vs. "routers"

From: "Christian Huitema" <[email-masked]>
Date: Tue, 25 Nov 2003 10:29:49 -0800

> The distinction between routers and hosts and the criteria to separate
> between them is one which I perceive as having been well established
> in Internet technology for a Long Time.

Well, how do you qualify a PC running a software component like
Microsoft's "Internet Connection Sharing"? It appears as a host to the
ISP, and acts as a router for the local network. That software has been
available since at least 1998. 

But never mind PC. How do you qualify a home NAT that appears as a host
to the ISP, get an IPv4 address using DHCP, and then appears as a router
to the local network?

There are millions of these. So what exactly is "well established"?

-- Christian Huitema

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From: Havard Eidnes <[email-masked]>
Date: Tue, 25 Nov 2003 19:45:36 +0100 (CET)

Hi,

I'm sure you'll excuse my naivete, but at least to my mind, a box
performing packet forwarding service between different interfaces (be
they logical or physical) to carry traffic where it itself is not an
endpoint, makes a box fall into the general category of "a router".

How it gets it's address(es), or whether it additionally performs NAT
or NAT-PT functions shouldn't make a huge difference with respect to
whether it is characterized as a "host" or a "router".

Regards,

- Håvard

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From: [email-masked] (Jun-ichiro itojun Hagino)
Date: Wed, 26 Nov 2003 07:14:41 +0900 (JST)

not sure on which mailing list we should continue this discussion.

> available since at least 1998. 

	i guess you are using "host" to mean "being able to make TCP connection"
	here.  "host" in IPv6 spec refers to forwarding functionality, so
	XP with Internet Code Sharing would be a "router" under IPv6
	terminology.  it is not unusual for a router (device that foward packet)
	be able to make outgoing TCP connection.

itojun

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From: Zefram <[email-masked]>
Date: Tue, 25 Nov 2003 18:47:28 +0000

>to the ISP, get an IPv4 address using DHCP, and then appears as a router

The NAT divides the network into two areas, the difference between them
being that certain things look different when seen from points of view
in the two areas.  One of the things that differs is whether the NAT
box appears to be a router or a non-routing host.

-zefram