O Plameras wrote:
Peter Hardy wrote:
O Plameras wrote:
4. Prevent customers of ISP from running WWW(FTP,MTA,etc) sites without
paying for fixed ip number(s).
Sorry? How does a dynamic address help here? Dynamic DNS services make
actually locating a service a snap. Only effective firewalling
prevents access to the service.
Clarification; prevent users from using the services for profit without
paying for
public ip addresses.
For users to access a WWW site say, 'www.domain.com.au'(FQDN) one must
have DNS entries in
one or more DNS servers with 'www.domain.com.au' with ip address like
203.7.132.1
or 'www.domain.com.au' with ip address like 203.7.132.0/32, etc.
Of course, users can put ip address instead of FQDN but it means that
each time your server
is disconnected and re-connected the users have to use different ip
addresses to access your
service. Not suitable for commercial operations.
If you have an alternative can you show us ?
Uh, I mentioned dynamic DNS in passing earlier. The Linux DHCP client
has hooks built in to issue DNS updates whenever it gets a new lease.
Another alternative is a daemon that polls the IP address and updates a
service like http://dyndns.org/ whenever it notices the IP address
changing. I'm using one of these to point casa.dyndns.tv at my ADSL
link, which is notorious for changing its address a dozen times on a bad
day. But the hostname always resolves to the current address, and
there's very little stopping me from registering, say,
stibbonsmegacorp.com, putting a zone on an external name server (like,
say, the free service offered by xname.org), and CNAMEing it to my
dyndns hostname.
No, I don't consider it terribly suitable for a commercial operation
either, but there's no pressing technical reason why not.
But really, this is getting why out of scope for a discussion on DHCP.
But, to answer your question, DHCP makes networking easy. Routers come
preconfigured with working DHCP server. All the user has to know is to
plug in to the switch and configure their computer to find an IP
address automatically. Seeing as that's the default for Windows and
most Linux installers, home networking has become pretty much a
no-brainer unless you *want* to get your hands dirty in it.
OK for off-the-shelf routers.
What about Linux boxes configured as routers because one does
not wish to pay anymore for a black-box modem/router apart from
just ADSL modem ? One still has to configure DHCP.
...then there's a good chance that you *want* to get your hands dirty in
networking. But, if not, configuring a DHCP server means you only have
to do your network setup once.
--
Pete
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