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From: DHARRIS@applelink.apple.com (Davie Harris)
Newsgroups: comp.protocols.appletalk
Subject: Re: Appletalk Phase 1 - 2 Question.
Message-ID: <11907@goofy.Apple.COM>
Date: 29 Jan 91 23:18:22 GMT
References: <9101291116.aa27259@COR2.PICA.ARMY.MIL>
Sender: usenet@Apple.COM
Organization: Apple Computer Inc.
Lines: 61

In article <9101291116.aa27259@COR2.PICA.ARMY.MIL> smwall@PICA.ARMY.MIL 
(Steve Wall, SFAE-AR-HIP-SY) writes:
> I've learned a lot about some advanced networking options, but since 
this is
> a forum for 'experts', a level of knowledge is presumed that I don't 
have.
> One specific area where I seem to be quite ignorant is on Appletalk 
Phase I
> vs Phase II.  I'm under the impression that Phase I is what you get when
> you just daisychain a small group of Macs and printers together with 
Localtalk

While I work at Apple, even in a networking software quality organization, 
this isn't an "official" Apple explanation - this is just how I understand 
it.  Also, since you specifically talked about an EtherNet solution I'll 
confine my explanation to EtherNet (and EtherTalk software) and LocalTalk 
only.  Please note that I'm referring only to Apple's released products 
cuz' I don't know how other folks stuff works.  With that disclaimer 
aside, here goes.  

Where EtherNet is concerned, whether any given Macintosh is using Phase I 
EtherTalk software is decided by the ADEV (what you click on in the 
Network Setup Control Panel item).  EtherTalk Installer v 2.01(the current 
version of the disk that comes with the Apple EtherTalk NB card) will 
install Phase II EtherTalk software.  You may choose to install Phase I 
support by dragging the EtherTalk v1.2 ADEV from a folder located on the 
EtherTalk installer disk to the System Folder of the Macintosh using 
EtherNet.  Once this is done, the Macintosh is rebooted, and the EtherTalk 
v1.2  ADEV is selected in the Control Panel (provided you're connected to 
a valid EtherNet network) that Mac will be sending Phase I packets.  
Simply following the installation instructions with the EtherNet will 
result in Phase II EtherTalk being installed.

If you are putting up a new network, that is there is no existing 
Macintosh EtherNet network that you'll be adding to, the question of "do I 
use Phase I or Phase II" should be moot.  Phase II is the current 
implementation and should be used.  The only reason (under this 
circumstance) that Phase I vs. Phase II would be raised is if you want to 
use a non-Apple router or bridge that happens to only route Phase I 
packets (just one or two of the products I've heard about).

Because every Macintosh has LocalTalk capabilities built in, AppleTalk 
software is installed with System Software.  Prior to System Software 
6.0.3, LocalTalk was Phase I.  Beginning with System Software 6.0.3 and 
with each subsequent version of System Software LocalTalk has been Phase 
II.  The differences between Phase I LocalTalk and Phase II LocalTalk are 
not as great as the differences between Phase I EtherTalk and Phase II 
EtherTalk, but they do exist.

The thing I want to make clear is this:  With the exception of the case I 
noted above (3rd party products...), Phase I or Phase II is not a question 
of hardware - it's a question of software.

=========================================
Davie Harris
Apple Computer Inc.
Networking and Communication Quality

The opinions expressed in this document are mine.  All mine.  They don't 
belong to anybody else.  When you're done with them, give them a good meal 
and send them home.