nanog mailing list archives

Re: who offers cheap (personal) 1U colo?


From: "Stephen Sprunk" <stephen () sprunk org>
Date: Sun, 14 Mar 2004 19:14:49 -0600


Thus spake "Vivien M." <vivienm () dyndns org>
Actually, you're forgetting what I think is the biggest reason for doing
this: before the user registers via the web-based DHCP thing, they
are shown the AUP and have to say they agree to it. If you just leave
straight IP connections available in rooms, and people violate the AUP,
they can QUITE credibly argue "But I never read this AUP". The
web-based DHCP registration system prevents that.

Students have an existing legal relationship with the school; they can be
required to accept the AUP in writing at some point during the enrollment
process.

Other advantages would be
A) It prevents students (or at least, all but the most clueful) from
taking
multiple IPs and having hubs and such in their rooms

There's nothing inherently wrong with that.

B) It makes it very easy to track what MAC address/IP address is which
person, as you yourself admitted. Sure, this system requires a bit of
effort
to set up initially (though I think open source implementations are easily
available), but afterwards, you don't need to have your most clueful
network
engineer dig through to try and figure out which room is what IP. If you
lower the clue level required to operate an abuse desk, I would argue you
improve its efficiency in many cases...

Tracking an IP address to a particular switch port via ARP and bridging
tables is straightforward; however this relies on detailed cabling plant
data.

C) It avoids issues of changing ports. Let's say I'm in room 101, and my
friend Bob is in room 102. I take my laptop to Bob's room and plug it
into the network and go and do something dumb... If you hunt down my
MAC address to a particular port, it looks like Bob is the AUP violator.
If you have a registration system, you know that this MAC address
belongs to me, not Bob.

Or, if you use 802.1x, you can skip the MAC registration and identify the
user directly each time he logs in.

Oh, and what about wireless networks? I have my nice 802.11b card,
how do you propose to track that without MAC registration (or hackish
VPN systems, which are also deployed in some campuses)?

802.1x

S

Stephen Sprunk        "Stupid people surround themselves with smart
CCIE #3723           people.  Smart people surround themselves with
K5SSS         smart people who disagree with them."  --Aaron Sorkin


Current thread: