[Info-vax] DECserver/LAT across DECnet areas?

[Scott Dorsey]

=?UTF-8?Q?Arne_Vajh=c3=b8j?=  <arne at vajhoej.dk> wrote:
>On 7/22/2023 7:07 PM, Scott Dorsey wrote:
>> LAT is not decnet.  Vaxcluster isn't decnet either.  LAT is its own protocol,
>
>Yes.
>0800 IPv4
>0806 ARP
>6001 MOP load
>6003 DECnet
>6004 LAT
>6007 SCA/LAVC

This is culturally very different than modern systems where everything is
running IP and only what is on top of TCP or UDP is different.  In the 
early era of Ethernet, all kinds of different packet types could be found
over the same Ethernet segment.  How they travelled from segment to segment
(or didn't) varied depending on the environment and the protocol.  It was
not unusual to find multiple buildings networked together with IP routers
but which also had Appletalk routers running in parallel with the IP routers
to carry Appletalk traffic as well as IP traffic.

The way described with VMS is more efficient and has much less overhead than
encapsulating everything into IP, but it doesn't scale very well because of
the routing difficulties.  Back in the eighties we saw giant bridged networks
of a thousand or more nodes and it became pretty clear this was a bad idea.
But if you route instead of bridge, you need to route all the different kinds
of protocols....
--scott
-- 
"C'est un Nagra. C'est suisse, et tres, tres precis."