(no subject)

[Jeff Vian]

On Fri, 2004-07-09 at 16:20, chicks at chicks.net wrote:
> On Fri, 9 Jul 2004 alan <alan at clueserver.org> wrote:
> > I don't understand why you need multiple mac addresses.
> 
> It boils down to wanting 5 routable IP's and the nasty cable company 
> require one MAC for each IP they assign.  There is no rational reason for 
> this, but they're addimant.
> 

This makes perfect sense from their point of view.  They have to set up
the system to authorize the connection and assign an IP. The only way
they have to confirm it is an approved machine is to use the MAC address
to check against a database for assigning IPs.

My cable provider uses the mac address of the modem to assign the IP,
and the machines behind the modem are allowed up to 5 addresses if I pay
for them (I only have one).  Since I have never used more than one IP I
have not checked the requirements for additional IPs.
 

> > Maybe if we understood the goal of what you were trying to accomplish, we
> > might be able to help better.
> 
> Does it make more sense now?
> 
> > If you just want to have multiple machines behind the firewall, just use
> > NAT and non-routable IP addresses (192.168.x.x).
> 
> That's not it at all.
> 

AFAIK the only way to get 5 distinct IPs from the provider is to have 5
physical devices with unique mac addresses.  

This is not necessarily related to the mac address, but the protocol and
software they use to identify devices.  With Linux you can have up to
256 unique IPs on each NIC.  Most other OSes are limited to one IP per
NIC.