P1394 Mail Archive: P1394> Print Protocols

P1394> Print Protocols

ALAN_BERKEMA@HP-Roseville-om2.om.hp.com
Tue, 17 Feb 1998 14:15:15 -0800


This was "RE: P1394> Rough SBP-2 & IP1394 core component ROM sizes"
however I figured it was time for a new name.

--------------------------
Ozay Oktay wrote:
I have been quietly monitoring this discussion on the reflector. So
far this is the best analysis I have read.

I agree with Brian almost entirely.. When preparing a standard we must
look into the future. We could be accommodating but we should never be
constricting for the sake of backward compatibility.

Best Regards

Ozay Oktay
Canon Information Systems
-------------------------------

I will second that, good job Brian.

So, from attempting to follow the discussion it seems to me that we have.

1) 1284.4 over SBP-2 over 1394.

Rough consensus that this is not a great idea.

2) 1284.4 over 1394.

I don't think this works by itself? We still need a layer that takes the
1284.4 packet and puts it into a 1394 packet with a 1394 address. As Brian
and others have mentioned DFA does this, however, DFA does not handle out
of order, lost or duplicate packets.

3) SBP-2 over 1394.

Has merit. Good native 1394 solution that takes advantage of 1394's memory
address capabilities and works well with descriptor based DMA.

If PC nodes only want to be Initiators we don't have a symmetric solution.
I think we can make it work, though, I am concerned that non PC peers that
implement both Target/Initiator functions would need to communicate with
each other in a different way than when they communicate with a PC?

4) DPP over 1394.

Sounds good. I have not seen enough of the detailed mechanism to determine
if it delivers (I need to learn more about DPP). Did receive some comments
at the TA about totally inventing a new mechanism instead of reusing
existing protocols, though it could be the right answer.

5) TCP/IP over 1394.

I think this is a given. (IP happens). This could give us printing similar
to the way it works today, as well as all the new internet possibilities.
Address administration and configuration, (DNS and DHCP and others as
Michael points out), make a full implementation larger than some devices
might like. Not sure of the use model?

Conclusions?

Alan