Subject: Topological Motivation for draft-ohta-root-servers-01.txt?

From: Steve Mattson <[email-masked]>
Date: Wed, 07 Jul 1999 13:07:35 -0400

Hello everyone,

Now that things have settled down a bit, I'd like to ask a question 
about a different aspect of the shared root server debate.  I believe 
that draft-ohta-root-servers-01.txt is the latest version of that i-d.

Upon reading it, and previous versions of same, I have noticed the
repeated country-specific references as motivation for the draft.
However, it appears that the operational changes proposed in the
draft have very little to do with national borders but instead with
network topology issues involving adjacent AS's and BGP routing.
It would appear that the advantages of the changes proposed in the
draft would benefit any group with sufficient internal infrastructure
to support management of an instance of a shared root server, without
regard to the physical or political location of the equipment.

I believe that a reworded motivation section of this draft based solely 
on network topology concerns would allow for a debate centered on the 
issue at hand.  This would allow the draft to proceed without having to 
address what is "internationally fair" or how to determine an evolving 
weight factor for the default set of root servers which one overrides 
selectively within one's "local" Internet.  At the very least a statement 
could be added to this i-d which specifically declared the determination 
of the default set of root servers, or the default scope of those root 
server addresses not otherwise overridden, as being beyond the scope of 
the draft.

Apologies if I've only added to the current confusion,

Steve Mattson

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 8 Jul 99 7:53:16 JST

Steve Mattson;

> network topology issues involving adjacent AS's and BGP routing.

It reflects the fact that most of the current root servers are in US
and people in US, seemingly, do not so much feel a lot of root
servers necessary.

> issue at hand.

The description explain the motivation. Abstract wording backed up by
no real-world situation it useless.

It is a lot better to remove it totally than make it abstract.

> This would allow the draft to proceed without having to 
> selectively within one's "local" Internet.

What do you mean "local" Internet?

The proposal is for the global Internet.

> At the very least a statement 

It is determined to be an empty set.

The i-d specifically declares that all the root server addresses can
be overridden.

> Apologies if I've only added to the current confusion,

Don't mind. I certainly hate confusion but love chaos.

							Masataka Ohta

---

From: [email-masked]
Date: Thu, 08 Jul 1999 09:52:15 +1000

> It is a lot better to remove it totally than make it abstract.

	I suspect that it would be better to say that the servers
	need to be distributed so that there is, in general, not
	the need to make inter-continental, trans-oceanic or
	satellite hops.  All of these types of links introduce
	large delays.

	I know there a political reasons at times to make the
	servers closer, but I believe the above critera technical
	critera should be used for determining how many root servers
	there are sharing a given unicast address and there rough
	placement.  The driving factor should be response times
	given an otherwise unloaded network.  Does < 100ms sound
	like a good figure?  While I don't know what the Atlantic
	adds to the RTT. I do know that satellites add ~400ms and
	the Pacific ~200ms.

	From an experimental point, BIND uses bands 128ms wide with
	the smallest band 64ms wide to select which nameserver to
	choose and it does a reasonable job of keeping named talking
	to the closest servers.  The size of these bands is adjustable
	at compile time.

--
Mark Andrews, Internet Software Consortium
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: [email-masked]

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 8 Jul 99 10:51:44 JST

Mark;

> 	satellite hops.  All of these types of links introduce

I have never heard such reasoning to have multiple (root)
servers.

If you insist, it can be added, but:

> 	Does < 100ms sound
> 	like a good figure?

are you saying that there should not be new root servers if the
TTLs to existing ones is < 100ms?

Note that it is not my business to fake a false or weakened reasoning
to have a lot of root servers.

						Masataka Ohta

---

From: [email-masked]
Date: Thu, 08 Jul 1999 12:28:52 +1000

> to have a lot of root servers.
	I want root servers that are reachable in a timely manner.
	I don't want all the root servers to become unreachable due
	to single point of failure.

	For TCP streams it does not matter so much where the servers
	are as TCP is *not* a stop and go protocol.  DNS/UDP is
	however and the RTT is a big consideration in sighting root
	(and TLD) servers.  If the server is just over the border
	the is not necessarilly a good technical reason to have a
	root server in this country.  If the root server is a long
	way away topologically / RTT wise there is.

	If there is a root server in France I can see no good
	technical need to have one in Monaco.  Similarly Singapore
	w.r.t. Thialand.

	We should be defining the siting of servers on technical 
	grounds not politcal ones.  If the are politcal reasons are
	strong enough they will influence the underlying technolgical
	interconnects enough that the technical solution will match
	the desired political one.

	Mark

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 8 Jul 99 11:39:18 JST

Mark;

> 	technical need to have one in Monaco.  Similarly Singapore

You are trying to create a political problem on how to stop people
in Monaco have their own root servers.

> 	grounds not politcal ones.

No, we are not defining the siting of servers. That is a pure
political issue.

You can say some root server technically desirable. But, you
can't say it technically forbidden.

We are documenting a technical operational guideline, after the
siting of servers is somehow determined.

>	If the are politcal reasons are

That's what is happening.

						Masataka Ohta

---

From: [email-masked]
Date: Thu, 08 Jul 1999 16:49:48 +1000

> in Monaco have their own root servers.

	No.
> No, we are not defining the siting of servers. That is a pure

	The whole premise of draft is couched in political terms.

	A country is a political unit.  You have made the assertion
	that each country needs at least a root nameserver.  You
	however have not justified that assertion.

	I can't at the moment see the need for Australia to have
	a root nameserver for political reasons.  I can however see
	why it should have several for technical reasons.  This draft
	may actually provide a way to do that without some of the
	detremental effects related to have a root nameserver.

	I would suggest that the motivation be re-couched in technical
	terms related to response time, load and traffic flows and leave
	the geo-policatical reasons for have a root nameserver to one
	side.

> can't say it technically forbidden.

	I didn't say it was technically forbidden.

---

From: Randy Bush <[email-masked]>
Date: Thu, 8 Jul 1999 00:13:20 -0700 (PDT)

> in Monaco have their own root servers.

i suspect not.  there is a presumed technical problem of a limit on the
number of root server ip addresses.  so spreading them to effect maximal
technical effect.  talking about countries' rights is creating political
issues.

randy

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 8 Jul 99 15:52:34 JST

Mark;

> > in Monaco have their own root servers.

What a technical elite you are.

> 	The whole premise of draft is couched in political terms.

OK. I will limit the amount of explanation of the motivation, which
contains potilical terms, less than 5 pages long.

						Masataka Ohta

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 8 Jul 99 16:07:31 JST

Mark;

I have a construtive suggestion you can do immediately.

There are people who want to have root servers.

Some of the current root servers are located so closely,
according to your technical criteria, each other.

So, you can convince people operating such root servers
to not to do so and delegate the freeed slot to others.

						Masataka Ohta

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 8 Jul 99 16:24:35 JST

Randy;

> i suspect not.

Do you remember that European NIC refused some IP address allocation
requests because there are private use addresses?

> there is a presumed technical problem of a limit on the
> number of root server ip addresses.

The question is, why do you think it a problem.

> talking about countries' rights is creating political
> issues.

It's fairness, not right.

But, if the technical problem is unsolvable, yes, there is a
political issue regardless of whatever I talk in the draft.

The situation, however, is that there are various ways for some
entiry including a contry to have their own root servers.

So, I wrote:

   With administratively scoped unicast addresses, any entity, including
   a country, can use the addresses for its local root servers and set
   the scope of the routing ranges of the addresses appropriately.

   Note that operations similar to that described in this memo are
   possible today locally without global coordination by any operator
   who may be irritated by the lack of his control on (sufficiently
   many) root servers, which may be a source of some operational
   problems. This memo is an attempt to document the way to solve the
   problem in a least harmful manner.

							Masataka Ohta

---

From: Randy Bush <[email-masked]>
Date: Thu, 8 Jul 1999 00:57:58 -0700 (PDT)

the swiss have always wanted an ocean for their navy.  they have a cultural
right to one.  why do you not share yours as you have so much?

randy

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 8 Jul 99 17:42:20 JST

Randy;

> right to one.  why do you not share yours as you have so much?

Most of the ocean does not belong any country and is already
shared internationally.

> > 	grounds not politcal ones.

Do you also think so?

							Masataka Ohta

---

From: Randy Bush <[email-masked]>
Date: Thu, 8 Jul 1999 02:07:38 -0700 (PDT)

>> grounds not politcal ones.

yes.

randy

---

From: Gunnar Lindberg <[email-masked]>
Date: Thu, 8 Jul 1999 11:44:58 +0200 (MET DST)

To add more fuel to this interesting debate...

Please note that "country" may be less relevant or may not even be
relevant at all. "ISP" may in fact be the better term - and ISPs
tend to cross country borders...

The sad news, however, is there are more ISPs than countries and each
ISP may want its own root server(s). Assume a country with two large
ISPs. I find it extremely unlikely that one of them will accept that
the other ISP runs that country's copy of the root server. So, either
there must be some neutral organization or they'll have one each.

My 1c worth is for technical arguments on where root server copies
should be located, but the optimum solution should preferably scale
up to each ISP having several copies of the root server. It would be
nice to hear a BGP expert claim the current draft does.

	Gunnar Lindberg

>From [email-masked]  Thu Jul  8 11:06:36 1999
>From: Masataka Ohta <[email-masked]>
>Message-Id: <[email-masked]>
>Subject: Re: Topological Motivation for draft-ohta-root-servers-01.txt?
>To: [email-masked] (Randy Bush)
>Date: Thu, 8 Jul 99 17:42:20 JST
>Cc: [email-masked], [email-masked]
>In-Reply-To: <[email-masked]>; from "Randy Bush" at Jul 8, 99 12:57 am

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 8 Jul 99 19:52:00 JST

Randy;

> >> grounds not politcal ones.

Then, according to Mark's example, if there is a root server in
France and there is no technical grounds to have one more in Monaco,
what will happen?

Do you want to stop people in Monaco operate their own root
servers?

If you don't want it, what is the point of defining the siting?

If you want it, how can you enforce it? What if, Monaco government
legislates that Internet users and providers in Monaco must use
Monaco local root servers?

							Masataka Ohta

---

From: Randy Bush <[email-masked]>
Date: Thu, 8 Jul 1999 04:27:20 -0700 (PDT)

> France and there is no technical grounds to have one more in Monaco,

insufficient data.  the example talked about countries as opposed to
network topology, bandwidth availability, ...

> Monaco local root servers?

it is said that once upon a time the tennessee legislature declared that pi
had the value three.  this may have affected my perception of government
edicts.

randy

---

From: Masataka Ohta <[email-masked]>
Date: Thu, 8 Jul 99 21:42:50 JST

Randy;

> network topology, bandwidth availability, ...

The example is Mark's and should be assuming appropriate network
topology and bandwidth availability in related locations.

> had the value three.  this may have affected my perception of government

In this case, the technical fact is that:

Who, do you think, is attempting the stupid enforcement?

						Masataka Ohta

---

From: [email-masked]
Date: Thu, 08 Jul 1999 23:15:04 +1000

> France and there is no technical grounds to have one more in Monaco,

	Nothing.  Will they get significantly better service?  I doubt it
	unless the server in France is overloaded.
> Do you want to stop people in Monaco operate their own root

	I said there was no need, not that they can't do it or that I
	wish to prohibit them doing it.

	The siting of server should be based on need.

	I think Australia needs root servers based on excessive RTT to
	get to the current set of root servers.  Only 30ms of the times
	below is related to my local link.  After that all the links
	until the packet gets out out the country are 34M or better and
	reasonably unloaded.  You will note Japan hosts the closest root
	server.

A round-trip min/avg/max = 538.075/564.123/618.585 ms
B round-trip min/avg/max = 395.34/414.388/511.844 ms
C round-trip min/avg/max = 551.811/574.045/636.487 ms
D round-trip min/avg/max = 545.681/564.311/622.53 ms
E round-trip min/avg/max = 482.533/502.24/570.518 ms
F round-trip min/avg/max = 481.896/495.207/528.304 ms
G round-trip min/avg/max = 555.316/568.384/615.337 ms
H round-trip min/avg/max = 460.838/491.312/568.309 ms
I (no response)
J round-trip min/avg/max = 530.988/560.705/637.963 ms
K round-trip min/avg/max = 627.765/658.583/816.851 ms
L round-trip min/avg/max = 391.142/412.013/480.743 ms
M round-trip min/avg/max = 233.128/264.374/419.544 ms

	Another technical reason for adding an additional root should be
	to load share.  And yet another to provide redunancy against single
	point failures.
> If you don't want it, what is the point of defining the siting?

	So that we get resonably uniform service levels wherever you
	are in the world.  This is patently obvious that this is not
	the case at the moment.  Below are the RTT as measured from
	California.  The worst cases below are better than the best
	cases above.

A round-trip min/avg/max = 64.002/64.386/64.73 ms
B round-trip min/avg/max = 16.22/16.717/17.87 ms
C round-trip min/avg/max = 90.174/110.793/233.235 ms
D round-trip min/avg/max = 190.128/216.845/235.791 ms
E round-trip min/avg/max = 7.522/8.081/9.097 ms
F round-trip min/avg/max = 4.644/4.737/4.817 ms
G round-trip min/avg/max = 179.227/394.412/691.453 ms
H round-trip min/avg/max = 75.882/76.917/80.992 ms
I round-trip min/avg/max = 162.517/166.611/170.374 ms
J round-trip min/avg/max = 66.372/66.617/67.103 ms
K round-trip min/avg/max = 150.063/151.216/152.626 ms
L round-trip min/avg/max = 19.218/19.851/20.908 ms
M round-trip min/avg/max = 159.566/170.415/262.884 ms

	We can make the technology find the close servers, but they
	need to be there in the first place.  We need to define what
	is acceptable close.  It does not matter if close is just
	across a border.

	Mark

---

From: Randy Bush <[email-masked]>
Date: Thu, 8 Jul 1999 06:24:32 -0700 (PDT)

> topology and bandwidth availability in related locations.

apologies for being dense.  what will happen is morocco and france can
sort out where the root server is.  if they are both served by the same
isp, they may have 42 root servers, all with the same globally visible ip
address.  some guy has a draft on how to do this. :-)

randy

---

From: Masataka Ohta <[email-masked]>
Date: Fri, 9 Jul 99 8:30:33 JST

Randy;

> sort out where the root server is.

Morocco in Afrique should better have their own.

> if they are both served by the same

DA wrote it. Don't panic.

						Masataka Ohta

---

From: Masataka Ohta <[email-masked]>
Date: Fri, 9 Jul 99 13:10:06 JST

Mark;

> 	unless the server in France is overloaded.

Irrelevant.

Or, can you try to stop the operations of, say, InterNIC root server,
saying the operators that their operation does not contribute to the
significantly better service?

BTW, it is evil for you to judge the significance of the improvement.

> 	The siting of server should be based on need.

If the seed were limited, yes.

> 	are in the world.

Uniform service level?

As long as someone, not you, can define the service level, that
person may be satisfied.

But, the requirement to the service level is not uniform.

							Masataka Ohta

---

From: [email-masked]
Date: Fri, 09 Jul 1999 15:18:31 +1000

> If the seed were limited, yes.

	The sites are limited.  If they were unlimited just let ever
	nameserver in the world secondary "." and be done with it.
	Can the existing root nameservers cope with however many million
	servers there are in the world all deciding within the refresh
	interval to transfer a copy of the root zone?  Remember there is
	still exponential growth here and we want the result to still be
	managable in 10 years time.  This is what this draft taken to it
	ultimate extreme leads to.

	If we want to stop short of that there has to be a critera for
	saying, "Yes, You can transfer the root zone." or "No, You are
	not allowed to transfer the root zone."
> > 	So that we get resonably uniform service levels wherever you

	Would you say that the service levels relativly uniform around
	the world?  I demonstrated the I could pick 2 well connected
	sites in the world and have vastly different service levels.
	Isn't the lack of uniform service at the moment driving this
	draft?  Why do you say each country needs a root server?  Is
	it prestige?  Some misguided nationalistic pride?  Or is so 
	that they can get timely responses?

	Every country does not need a root name server.
	Every country needs good root name service.

---

From: Masataka Ohta <[email-masked]>
Date: Fri, 9 Jul 99 14:17:00 JST

Mark;

> 	The sites are limited.

And the Internet is limited, too.

> 	interval to transfer a copy of the root zone?

Of course.

> 	Every country needs good root name service.

Every country needs good root name service at their definition
of the goodness.

							Masataka Ohta

---

From: [email-masked]
Date: Fri, 09 Jul 1999 16:10:33 +1000

> > 	interval to transfer a copy of the root zone?

	Then lets do it and put this draft in the bit bucket!!!!

	It's easy enough to make nameservers choose a root server
	at random to transfer from:-)

> Every country needs good root name service at their definition

	Good to hear that you agree with me that it is service
	level that is driving this and not politics.  Now can you
	make the motivation section reflect that and the belief that
	most of us in this working group have that there are parts of
	the world that don't have reasonable service levels and it is
	because there are not enough "slots" available to put root
	servers everywhere they should be to get these reasonable
	service levels.

	Mark

---

From: Masataka Ohta <[email-masked]>
Date: Fri, 9 Jul 99 15:08:37 JST

Mark;

> 	Then lets do it and put this draft in the bit bucket!!!!

It is so obvious that it does not worth spending lines.

> 	at random to transfer from:-)

Urrr, it is certainly true that the average diameter of random
graphs is still logarithmic to the number of nodes. However, the
degree of each node is not bounded. Worse, there is a small
possibility of graph separation.

So, it's better to use more systematic approach based on a tree
with additional redundant edges.

> 	level that is driving this and not politics.

What, do you think, defines the service level?

Hint: It is not technology.

							Masataka Ohta

---

From: [email-masked]
Date: Fri, 09 Jul 1999 17:17:51 +1000

> It is so obvious that it does not worth spending lines.

	Then why did you do it:-)

> Hint: It is not technology.

	It is the end customers.  They don't care if the root servers
	are in or outside the country they are currently in provide they
	get a reasonable level of service.  Neither should this draft.

	The only places in the world where the end customer will be saying
	"I want a root server in the country because there is not one" are
	those countries where only way to get reasonable service levels is
	to have one in the country.  I've heard plenty of time "We need
	another root name server in Europe" but very seldom "We need
	another root name server in <pick a European country>".

	I say we need servers in Australia because I know that there is no
	way to provide the service levels needed without physically
	locating the servers in Australia.  But Australia is large and it
	does not have close neighbours.

	Root level service should be measured in milliseconds or 10's of
	milliseconds not 100's or 1000's as it currently is.  A large
	portion of the world gets that service now.  They are not arguing
	for more servers.  The rest of the world is.

	Mark

---

From: Masataka Ohta <[email-masked]>
Date: Fri, 9 Jul 99 16:21:29 JST

Mark;

> 	Then why did you do it:-)

Lines in RFCs cost time of so many people that I rather spend my
time for lines in the mailing list.

> 	It is the end customers.

End customers, local ISPs and their assemblies upto the United Nations.

							Masataka Ohta

---

From: Geoff Huston <[email-masked]>
Date: Fri, 09 Jul 1999 21:26:07 +1000

>	does not have close neighbours.

I find it impossible to agree that one of 13 root nameservers should be
located on an isloated island in the South Pacific with a population
of a few fractions of a percent of the total world because one or two
of the local inhabitants of that island feel that their needs usurp the
legitimate needs of many hundreds of millions of others.

I say we need root nameservers to make the DNS work efficiently for
_everyone_. Given that statement we need to examine what is appropriate
to make the technology work for all, and not a "lets pick my favourite
country" nonsensical trash.

   Geoff

(some countries, like Australia, are not even comprehensively internally
connected, and the transit across the street sometimes heads both around
the globe and far out to space. Countries do NOT host root nameservers,
its a network topology, reliability, and traffic optimisation thing.)

---

From: [email-masked]
Date: Fri, 09 Jul 1999 22:58:45 +1000

> its a network topology, reliability, and traffic optimisation thing.)

	Geoff,
		no one is try to usurp anything.  The point of the draft
	is how do we provide *many* root (or tld) name servers on a single
	advertised IP address and manage them effectively.  Distribute route
	information, handle fault reporting. etc.

	Ohta-san's premise is that every country needs a root name server.
	My premise is that every body / country needs good root name service.

	By good I mean response times over reasonable infrastructure in
	the order milliseconds to 10's of milliseconds, not as there is
	now of 100's of milliseconds.

	The only way Australia can have that level of service is for
	servers to be located in the country.  The physics does not
	allow them to be anywhere else.  This however is not the case
	in Europe or other places in the world.

	This is a arguement about what the premise should be in the
	draft.

	Mark

---

From: Masataka Ohta <[email-masked]>
Date: Sat, 10 Jul 99 0:10:28 JST

Mark;

> 	information, handle fault reporting. etc.

Thanks.

But,

> 	Ohta-san's premise is that every country needs a root name server.

That is a misunderstanding of you I have had no time to correct.

I think at least every contry with developped domestic internet
needs several root name servers.

If I said every ISP needed it, there was a possibility that some
conter argue that many ISPs can share a root server.

But, I was too optimistic, as you even say that many countries can
share it, which will ultimately lead to the silly conclusion that the
current number of root servers is large enough.

No, you can't convince some people who think they are receiving
good root name service are actually receiving poor service.

So, we should not involved in the argument on how many servers
we need and just specify a way to allow arbitrary many root name
servers.

> 	My premise is that every body / country needs good root name service.

Geoff made a good point that several ISPs in Australia needs
several (or, at least one?) root servers, which is different
from your definition of "good root name service" that a
single server is fine.

BTW, the other point of you I have had no time to correct is that delay
is not the only factor. Fault tolerance, for example, is another
important factor and I may be missing other factors. The best
strategy is just specify the way to have a lot of root servers
with underestimated reasons on why we need many without specifying
when to have them.

							Masataka Ohta

---

From: [email-masked]
Date: Sat, 10 Jul 1999 08:31:57 +1000

> with underestimated reasons on why we need many without specifying
	Ohta-san,
		I think we both agree, if we ignored borders, about
	what constitutes good root name service.  Redundant servers,
	relatively close RTT wise, sited so that single failures
	are unlikely to make the all unreachable.  The servers
	and links should also not be overloaded, this reflects back
	into RTT and packet loss.

	Just saying that every country needs a root nameserver does
	nor guarantee that people will get good root service.

	We, as a working group, should be able to define *good
	service* in measurable terms, as seen from the client.
	This sort of definition is much better that how we have
	defined root servers in the past.  It is a machine that
	can handle so many queries / second, has connections of at
	least dimmension X to at least Y places.

	Mark

---

From: Masataka Ohta <[email-masked]>
Date: Sat, 10 Jul 99 8:10:42 JST

Mark;

> 	what constitutes good root name service.

As we agreed, the definition of "good root name service" is defined
by, say, end users and is a subjective issue.

>	Redundant servers,

They are your subjecive definitions.

> 	nor guarantee that people will get good root service.

Exactly.

Just writing BCP does not guarantee that people will get good root
service.

It is not our business to give such a guarantee.

Let countries satisfy their citizens, ISPs their customers, according
to their definitions of the good root services.

They don't want you specify their requirements.

						Masataka Ohta