Subject: 5. IPv4LL is not about "dumbing down" current hosts

From: Stuart Cheshire <[email-masked]>
Date: Thu, 6 Feb 2003 02:30:36 -0800

I have seen assertions that the idea of a device that implements only 
IPv4LL addresses is to take a fully-functional IP host and "dumb it down" 
so it can't talk to anything further away than the local link.

I will try to explain the real issue below, and I will thank people for 
making an honest effort to understand and internalize this information. 
Willful refusal to understand this issue and willful misrepresentation of 
it does not help us reach a conclusion.

First I will describe two classes of device:

1. Current IP hosts. These support world wide connectivity to millions of 
other hosts, over distances of thousands of miles.

2. Current USB peripherals. These are limited to small clusters of a 
handful of devices, with cable lengths limited to about 16 feet.

My goal here is NOT to take existing fully-functional IP devices and dumb 
them down to make them less functional.

One of my hoped-for goals for Zeroconf is to take the current USB 
peripherals and move them up them to networks of a hundred devices, with 
cable lengths in the hundreds of feet, using standard IP-based 
communication protocols, instead of the device-specific communication 
protocols currently used by USB, FireWire, Bluetooth, etc. Ideally we'd 
like to do this while keeping the same price-point as current USB 
peripherals like printers. This makes the device better and more useful 
than it was when it was only a USB device. If we can acheive this (and we 
are starting to), then the next goal is to encourage printer vendors to 
make printers with full global IP connectivity -- and the requisite 
security to go with it -- and to continue to do it at an affordable price 
point.

Please try to think of IPv4LL-only in terms of a step forward for a 
device that is currently even more limited, not a step backwards for a 
device that already has full IP functionality.

Stuart Cheshire <[email-masked]>
 * Wizard Without Portfolio, Apple Computer, Inc.
 * Chairman, IETF Zeroconf
 * www.stuartcheshire.org