was bogon filters, now "Brief Segue on 1918"

Patrick Darden darden at armc.org
Thu Aug 7 12:47:02 CDT 2008

I've always enjoyed your posts Michael.  You are obviously an expert, 
with no patience for idiocy, and you always go for the throat and try to 
hurt the other person as much as you can.  Your messages are always very 

In this case, however, you are responding to a conversation that is 
pretty much over and done.  I've already received  umpty emails telling 
me how right I am, and another umpty emails telling me I am an idiot and 
I should go back to knitting.  Most of the latter were privately sent, 
and I appreciate both their candor and discretion....

The reasonable voices seem to feel that it doesn't matter if I am right, 
as the real world just doesn't care.  I have to agree with that.  That's 
kinda the whole point, I think.

The forward thinkers feel as you do that IPV6 is the real answer.  I 
believe I was the first to say that in this thread.

As far as the individual points that you satirize below--well ok then.  
We are not talking about people.  I was not the person who raised people 
as a metric.  Jump his case if you feel the need.  I was actually 
jumping his case about it myself, albeit tongue in cheek, and hopefully 
with no hard feelings.

However, the original conversation centered on  the best way to design 
private networks so that internetworking between companies who did not 
confer on eachothers' network design does not cause problems, and how 
very few companies follow RFC1918 very well in my experience.

Whether they fail at RFC1918  for real reasons or not, they still fail.

As far as companies that design their own networks so they have trouble 
interoperating with themselves--well, bummer for them.  I bet they wish 
they had done their design more efficiently instead of making "large 
sprawling" networks with plenty of room for growth for soda machines.  
Because you just can't assign enough IP address space for your soda 

"Cute sound bites does (sic) not make you an expert in anything. "  I 
agree with this too.   But just because it's cute, doesn't mean it's wrong.

--Patrick Darden

michael.dillon at bt.com wrote:
>> Your point seemed to be that 
>> it is not a large enough allocation of IPs for an 
>> international enterprise of 80K souls.  My rebuttal is: 16.5 
>> million IPs isn't enough?
> You don't seem to understand how IPv4 networks are designed 
> and how that interacts with scale, i.e. the large sprawling
> networks that international enterprises have. You don't simply
> count out x addresses per employee. Instead, you design a subnet
> architecture that a) can grow at all levels, and b) can be
> cut off the network when you sell off a branch operation or two.
> This leads to large amounts of IP addresses used up in padding
> at all levels, which then leads to these organizations running
> out of RFC 1918 space, a more and more common occurence. This,
> in itself, is a good incentive to move to IPv6, since the
> seemingly wasteful subnet architecture is considered best practice
> with IPv6, and a ULA prefix or two gives you lots of space to
> keep growing.
>>  What are we talking 
>> about then?  100 IPs per person--say each person has 10 PCs, 
>> 10 printers, 10 automated factory machines, 10 lab 
>> instruments, 49 servers and the soda machine on their 
>> network? 
> Nope. We are not talking about people, but about network
> architecture and topology. Two people in one office need
> two addresses. Put them in separate offices and they need
> two subnets. Topology dominates the design.
>> I don't think you have that many soda 
>> machines.  Even on 5 continents.  Even with your growing 
>> Asian market, your suppliers, and the whole marketing team.
> I believe the first two companies to run out of RFC 1918
> space (or to project that it would happen) are Comcast,
> and American cable provider in one continent, and a
> Japanese cable provider on a small Pacific island next
> to China.
>> //Err.  Doing it wrong does not justify doing it wrong.
> Cute sound bites does not make you an expert in anything.
> In any case, IPv4 is yesterday's news. Nowadays everyone is
> scrambling to integrate IPv6 into their networks and shift
> services onto IPv6.
> --Michael Dillon

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