Autor: o1bigtenor Data: CC: dng Temat: Re: [DNG] Request for information - - re: networking
On Mon, Jun 5, 2023 at 12:01 PM Rainer Weikusat via Dng
<dng@???> wrote: >
> o1bigtenor via Dng <dng@???> writes:
> > On Sun, Jun 4, 2023 at 6:05 PM Antony Stone
> > <Antony.Stone@???> wrote:
>
> [...]
>
> >> At this point it's useful to note that two addresses "disappear" from every
> >> network range and cannot be assigned to machines on the network - the first
> >> address and the last address.
>
> [...]
>
> > I seem to remember that 0.0, 1.1 and 255.255 were reserved from any group.
> > not allowed to use the 0.0 and the 255.255 as you mention and that 1.1 is the
> > router's address.
>
> The two special cases are 'host bits all zero' and 'host bits all
> one'. Both are reserved for IP-directed broadcasts (a feature nobody
> uses anymore today), the first reportedly because 4.2BSD used it for
> this, the second because it got later standardized by the IETF. There's
> nothing special about the first non-reserved address, eg,
> 192.168.1.1. It's commonly used for default gateway addresses. But
> there's also the other convention to use the last address for that, eg,
> 192.168.1.254, and both are just informal conventions.
>