In fact, we STRONGLY, STRONGLY, STRONGLY (can I say that louder?)
recommend that folks using AppleTalk-based services look at IP
alternatives. Apple now provides (as indicated below) printing over IP,
and with AppleShareIP alternatives, there are file sharing approaches
using IP as well. There are three basic (although I could easily add to
this list) reasons why we make this recommendation:
(1) AppleTalk (the protocol) does not scale well; it was designed for
small workgroup networks. The dynamic mechanism of choosing node
addresses, the 10 second broadcast interval of RTMP packets, the impact
of the AppleTalk Echo Protocol, the inability for zone information to be
dynamically propagated across routers, the kludge known as "extended
network" addresses all are indications of that.
(2) AppleTalk (the protocol) is inherently slower than IP; even Apple
has published findings that with the same hardware doing the same things
over the same switched 10 Mb/sec Ethernet, what can generate 9.3 Mb/sec
with IP can only do 7 Mb/sec. On a 100 Mb/sec connection, AppleTalk can
only generate AT MOST 35 Mb/sec. The reasons for this: the AppleTalk
ATP retry-acknolwedgement algorithm is nowhere near as efficient or as
effective as TCP and its congestion control/flow control mechanisms, and
Datagram Delivery Protocol (DDP) in AppleTalk only uses datagram packets
no larger than 586 bytes, even though an Ethernet frame can be 1500
bytes in length.
(3) A larger number of vendors (old and newer startups) are not
supporting AppleTalk in the next generation of Layer 4 gigabit speed
switches. Some are not even supporting IPX. The networking world is
becoming an IP world -- we will need to be ready for it.
-- Jim Gogan
Director, ATN Networking and Communications