Subject: RE: IP network address assignments/allocations information?

From: Ian King <[email-masked]>
Date: Mon, 29 Nov 1999 22:45:17 -0800

Yes, my ISP is charging me for my DNS entry -- a static entry made once in a
zone file, but I'm paying monthly to have a domain name!  Never mind that I
don't use their mail server or Web page service or DNS server....  

And yes, additional IP addresses were going to cost dramatically more.  NAT
was a simple case of economics... but on the other hand, I don't experience
any "lack" because of it.  I don't play UDP-based games or employ any of the
other relatively new protocols that are so sensitive to end-to-end-ness
(should they be? was that a valid assumption?), so a NAT is a great solution
for me.  

NAT would be bad if an ISP were using it to artificially expand its address
space; the use of NAT at the "small-time" end user's site seems quite
practical and beneficial, especially in a world where ISPs are going to hold
up non-naive users for ransom.  Cheers -- Ian 

-----Original Message-----
From: Richard Shockey [mailto:[email-masked]]
Sent: Monday, November 29, 1999 8:00 PM
To: Keith Moore
Cc: [email-masked]
Subject: Re: IP network address assignments/allocations information? 

At 07:02 PM 11/29/1999 -0500, Keith Moore wrote:
> > Many of the people who have deployed NATs are responding directly to the
> > address scarcity (and resultant cost). If you consider that many ISPs
now
> > have different pricing models for multiple IP addresses than they do for
a
> > single (regardless of bandwidth used), it isn't surprising.
>
>no, not surprising (and in fact some people predicted it), but
>it is surely unfortunate.

I can personally testify to the above comments. Consider...we are all IP 
professionals ...so we'd like to occasionally play with all of the 
wonderful toys we've built...at home. Our fathers stuck their heads under 
the hoods of cars or played with short wave radios...we play with IP.

Now try and ask your friendly neighborhood DSL or Cable Modem provider 
about getting a nice chunk of IP addresses. Well we all know what DSL 
really means ..._D_riveway _S_ite _L_iaison  or the modern version of "Who 
on first?".

You want to run a web server, DNS (from home?)  IPP printer accessible 
printer ( DUH what's IPP?), SIP phone .. pick your application.  To the 
service providers the request for IP addresses is some sort of strange 
signal that you're running a eCommerce site from home or worse a Game/Porn 
site. Something that they believe they should charge more money for.

The path of least resistance is just install a NAT. The market for NAT 
device/software products are being driven by in part the lack of IP4 
numbers but certainly the lack of knowledge, marketing skills or just plain 
greed of the ISP community.

Richard Shockey
Shockey Consulting LLC
8045 Big Bend Blvd. Suite 110
St. Louis, MO 63119
Voice 314.918.9020
eFAX Fax to EMail 815.333.1237 (Preferred for Fax)
INTERNET Mail & IFAX : [email-masked]
GSTN Fax 314.918.9015
MediaGate iPost VoiceMail and Fax 800.260.4464
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

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From: [email-masked]
Date: Tue, 30 Nov 1999 03:04:35 -0500

> (should they be? was that a valid assumption?), so a NAT is a great solution

Well.. Urm... TCP and UDP both assume that one endpoint is talking
directly in real time to another endpoint.  The NAT problems only
start when the protocol carries IP address/port information (such
as the FTP 'PORT' command), and the NAT isn't aware of that protocol's
translation requirements (If you see *this* at offset 80 of *that*
packet, smash it to read *foobar* instead).

I'll grant FTP an exemption, it came well before NAT units became
prevalent (Was there an FTP-over-NCP before The Great IP Deployment?).
However, I do agree that anybody designing a protocol in the last 3-4
years *should* have designed it to be firewall and NAT friendly.
(Yes, I know that can be difficult in practice.  I guess that's today's
"Welcome to Reality").

				Valdis Kletnieks
				Operating Systems Analyst
				Virginia Tech

---

From: [email-masked]
Date: Tue, 30 Nov 1999 03:04:35 -0500

Valdis Kletnieks

---

From: Keith Moore <[email-masked]>
Date: Tue, 30 Nov 1999 09:03:22 -0500

> (should they be? was that a valid assumption?), so a NAT is a great solution

understood.  and you may never miss any of those distributed applications 
or applications that want your end to be the "server" for the very reason
that NAT prevents them from having enough market share to be successful.

i.e.  just because you don't know what you're missing doesn't mean that NAT
hasn't done you harm.

> up non-naive users for ransom.  Cheers -- Ian 

if you think of NAT as a short-term strategy and are fully aware of its
limitations, it probably won't cause you much harm as an individual.  

then again, there are dozens of products out there claiming to offer
something like "internet connection sharing" without bothering to mention
the limitations of that approach...which seems like misleading advertising
at best.

Keith

---

From: Keith Moore <[email-masked]>
Date: Tue, 30 Nov 1999 09:03:22 -0500

Keith

---

From: Keith Moore <[email-masked]>
Date: Tue, 30 Nov 1999 09:09:35 -0500

> The NAT problems only
> translation requirements 

this is a popular misconception; it's a bit like saying that y2k
only breaks programs that store years in two digits.  

see http://www.cs.utk.edu/~moore/what-nats-break.html
for my attempt to list the various ways that programs can lose
in the presence of NATs.

Keith

---

From: Keith Moore <[email-masked]>
Date: Tue, 30 Nov 1999 09:09:35 -0500

Keith

---

From: John Day <[email-masked]>
Date: Tue, 30 Nov 1999 09:31:33 -0500

>packet, smash it to read *foobar* instead).

I would tend to agree.  As I have said elsewhere, NATs in and of themselves
do nothing wrong.  They are doing things within the Internet/Network Layer
that are perfectly legal.  (In essence, they are treating the network
address in much the same way that X.25, ATM, and MPLS treat their
addresses.)  The problem is that applications lacking an "application
address space"  are using the Network address space inappropriately.  In a
sense, we are making the same mistake the phone companies made when they
kludged their route-dependent address space to be location-independent
(first 800 numbers and then mobile).  They have since fixed their problem.
>prevalent (Was there an FTP-over-NCP before The Great IP Deployment?).

Actually, there was and the PORT command existed as a kludge.  The
preferred approach for the data connection was intended to be a fixed
offset from the telnet connection.  The PORT command, then called SOCK, was
inserted because BBN TIPs hardwired printers and such to certain sockets.
Not exactly an example I would recommend following.  The PORT command
should have been retired decades ago.

>(Yes, I know that can be difficult in practice.  I guess that's today's

Applications which need to communicate addressing information for their own
use should only  use  an application address space.  Now, the fact that we
don't have one is a bit of a problem!  ;-)  It would have been nice to have
one before we got this far.  How we get out of this mess at this point is
anyone's guess.

Take care,
john

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From: John Day <[email-masked]>
Date: Tue, 30 Nov 1999 09:31:33 -0500

Take care,
john