[HECnet] DECdns

[Johnny Billquist]

Paul...

On 2016-05-31 15:52, Paul_Koning at Dell.com wrote:
>
>> On May 28, 2016, at 11:00 PM, Mark Abene <phiber at phiber.com> wrote:
>>
>> DECdns serves a similar purpose to the real DNS, except it's
>> specifically for resolving DECnet node names to node addresses.
>
> That's a small part of what DECdns aimed to do.  The bigger part (and something that "real" DNS still struggles with) was to provide a fault tolerant, distributed, dynamically updated name-address mapping.

Paul, I'm sure there are a lot of things about DECdns that are both well 
designed and interesting. Unfortunately I know pretty much nothing about 
it. :-(

> At the time DECdns was designed, the Internet's DNS was basically just a text file connected to a trivial daemon, with updates done by sending new versions of those text files around.  That was roughly the same level of primitiveness that the DECnet Phase II through IV node name mappings had.  DECdns delivered a distributed database with automatic machinery for distributing updates reliably.

However, your description and/or understanding of DNS seems to be very 
weird. DNS have never been just a text file connected to a daemon. It 
sounds like you are conflating DNS and the pre-DNS /etc/hosts (or 
HOSTS.TXT) file, that was used in the early days. Which might match the 
time frame of DECdns. The HOSTS.TXT file was not even connected to any 
daemon. Your programs were expected to just read and parse the file 
themselves, as needed. Or at least on the systems I know about. Exactly 
how this worked could differ from one system to the next. But there 
wasn't anything called "DNS" at that time.

DNS is distributed, with automatic updating of secondaries from 
primaries. It is rather fault tolerant, and very scalable.

The one thing "lacking" have been an easy way of adding new information 
programatically, while at the same time ensure security and data 
validity. So you often still have the source of information for the 
primary server being managed in a text file. But that file is not sent 
around to other servers of the domain. DNS takes care of distribution 
and replication itself.

This adding have become a larger issue over time, as people are 
expecting to just plug in devices to the network, and then be able to 
refer to them by some name that should pop into the local DNS server.

	Johnny