[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [K12OSN] Gconfd trouble on new install



Actually,

192.x.x.x is NOT a class A address.

192.168.0.0 IS a private address.


Determining what class a certain IP address is in, requires
looking at the first few bits of the address.

0    Class A  0.0.0.0   to 127.255.255.255
10   Class B  128.0.0.0 to 191.255.255.255
110  Class C  192.0.0.0 to 223.255.255.255

The 10.0.0.0 network clearly falls into the first group
and is a Class-A address.  Basically, meaning the first 8 bits
specify the network, and the remaining 24 bits specify the host
within the network.

The 192.168.0.0 network falls into the Class-C range.

As for the 'NON-ROUTABLE', all of these addresses are fully
routable.  The real issue is that the 10.0.0.0 and the 192.168.0.0
networks are "PRIVATE".  that is, they will NEVER be allocated
to anybody, so they won't end up in the core routers on the
internet, therefore, those packets won't get routed on the
internet.

They MUST be routable, otherwise, how could you have your 
corporation setup with one department with the 192.168.0.0
network, and another department with the 192.168.1.0 network,
and they talk happily through a router.

Many routers allow you to setup filters to block such routing,
but it isn't required.

Jim McQuillan
jam Ltsp org


On Wed, 12 Jun 2002, Kirk Rheinlander wrote:

> Not specifically relevant to this post, but it brings up a question that I 
> am always asked.....
> 
> For newbies to IP, the 10. and the 192. (and 169.???) are all class A (16 
> million addresses per) blocks of addresses that are NON-ROUTABLE - things 
> that will not show up on the other side of a router. This means that by 
> using such an address set 1) your network computers can have the same IP 
> addresses as some other school / company / home / etc., without getting 
> stuff intended for someone else 2) not expose your computers to the outside 
> world directly. Network Address Translation (NAT) provides a single IP 
> address to the outside world, and remaps the traffic to the appropriate 
> inside address.
> 
> It is a lot more complicated, but this should answer the question "why 192. 
> addresses?" in K12LTSP default configurations.....and why the 10. address 
> in this post.
> 
> At 06:23 PM 6/11/2002, you wrote:
> >I have recently reinstalled with the latest on a single NIC system running
> >on the 10. subnet.
> 
> 
> 
> _______________________________________________
> K12OSN mailing list
> K12OSN redhat com
> https://listman.redhat.com/mailman/listinfo/k12osn
> For more info see <http://www.k12os.org>
> 

-- 





[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]