[ih] The history of "This" 0.0.0.0/8 network?

[Grant Taylor]

On 02/12/2019 11:55 AM, Michael Kjörling wrote:
> NCP. https://en.wikipedia.org/wiki/Network_Control_Program
> 
> The final transition from NCP to TCP/IP was in January 1983. RFC 801
> may be of interest.

I'm aware of NCP and the transition that you are referring to.

However, what I'm not sure of is what sort of addressing NCP used.  What 
little I've been able to find is that NCP addresses were different 
enough from IPv4.  So I am taking Dave's "0.0.0.0" to represent an IPv4 
address.  Perhaps I don't know enough about NCP to safely take that stance.

> I wasn't around at the time, but the January 1970 RFC 33 says on page
> 6 that NCP addressing was 24 bits of "user number" plus 8 bits of
> "host number" plus 8 bits of "another eight-bit number", 7 of which
> seem like they function largely as what we today refer to as "ports";
> one end of a connection was therefore identified by a total of 48
> bits, 8 of which describe the host. I don't see anything obvious
> actually specifying a format for how these addresses would be entered
> by or displayed to a user, only hints that hexadecimal notation may
> have been common.

That sounds decidedly not dotted quad format.  I guess depending on the 
values, there could be some overlap with other formats of an IPv4 address.

But I still think that Dave's "0.0.0.0/8" had in his subject is 
tantamount to IPv4.  Hence my train of logic.  ;-)

> This format allowed up to 2^8 hosts on the network, each with 2^24
> users, each with 2^7 simultaneous active bidirectional connections.
> 
> Note that "port" in NCP seems to have been a very different concept
> from "port" in TCP. My understanding is that NCP "ports" refer more to
> the physical links than to a logical property of a data connection.

ACK



-- 
Grant. . . .
unix || die