wicinski@NRL-CSS.ARPA (tim wicinski) (09/25/87)
We have aat least 4 different gateway s/w we've acquired over the years.
I want to know why so many, and why are they different..
Could someone fill in the blanks below, correct any errors, etc.? Most
of these are from Kinetics, but documentation doesn't really tell you
anything about them...
AT.gw.srec - if this is the "DDP Gateway" as Alisa tells me (since they
use this for there system) how is this different from DDP.srec ?
From what I have gatehered :
Used to join several AppleTalk nets using an Ethernet
backbone, one K-box per net.
Ethernet side uses special "AppleTalk on Ethernet"
packet type.
Used by AlisaTalk, TOPS/Unix,
udp.gw.srec = "the UDP gateway", uses IP routing to handle packets.
(From the Kinetics doc):
On AppleTalk side, accept:
(a) IP packets encapsulated in DDP/LAP packets
=> decapsulate and send on Ethernet
How are these recognized as such?
(b) DDP datagram destined for host on Ethernet
=> encapsulate in UDP datagram and send
How does K-box know that host is on
Ethernet? By a broadcast/reply?
On Ethernet side, accept:
(a) IP packet destined for node on Ethernet
=> encapsulate in DDP/LAP and send
(b) There is no analog of (b). There is no
way to get a DDP datagram back to an
AppleTalk host unless it is encapsulating
an IP packet.
Used by Ultra-Office
comb.gw.srec = "the combined gateway", latest version date = __?__
Presumably this g/w performs some combination
of at.gw.srec and udp.gw.srec. Handles multiple zones, and can
handle udp requests. does this replace the AT and the UDP g/w code ?
Any reason why it won't work with products mentioned above?
For any one gateway type, what are the consequences of having more
than one instance of the same gateway code running on K-boxes connected
to the SAME Ethernet and the SAME AppleTalk net?
For each pair of gateway types running in two Kboxes, what are the
consequences of each of the following cases? I.e., which ones are
meaningful and which ones are nonsense or will cause trouble, routing
loops, etc.
(a) Kboxes connected to the same Ethernet and the same AppleTalk net
(b) Kboxes connected to the same Ethernet but different AppleTalk nets
(c) Kboxes connected to different Ethernets but the same AppleTalk net
thanks
tim wicinski