SUBMITTED version 1.0 15 August 2003
IPv6 Operations WG (v6ops)
Tuesday, July 15 at 1545-1800
Wednesday, July 16 at 1530-1730
Bob Fink <firstname.lastname@example.org>
Pekka Savola <email@example.com>
Margaret Wasserman <firstname.lastname@example.org>
The minutes were edited by Bob Fink from various notes from
There were over 200 folk in attendance.
v6ops discussion: <email@example.com>
Subscribe to v6ops mail list: <firstname.lastname@example.org> "subscribe v6ops"
v6ops mail archive:
v6ops web site: <http://www.6bone.net/v6ops/>
v6ops Project Status:
Introduction and agenda bashing - 5 mins, Margaret Wasserman
current status - 5 mins, Margaret/Pekka
UNMAN Analysis discussion - 25 mins, Christian Huitema
Forwarding Protocol 41 in NAT Boxes - 10 mins, Jordi Palet
IPv6-IPv4 Translators in 3GPP Networks - 10 mins, Karim El-Malki
ISP Scenarios - 40 mins, Mikael Lind
ENT Scenarios - 40 mins, Yanick Pouffary/Jim Bound
v6-on-by-default - 25 mins, Alain Durand
5-10 mins presentation, remainder discussion
threedegrees - 10 mins, Christian Huitema
Security - discussion of what we should be doing - 45 mins, Chairs
NAT-PT Applicability Statement team report - 15 mins, Peter Barany
Writing IPv6 Applications report - 15 mins, Myung-ki Shin & Pekka Savola
Status report of IPv4 Survey drafts - 10 mins, Chairs
First Session: Tuesday, July 15, 2003 at 1545-1800
Introduction and agenda bashing - Margaret Wasserman
current status - Margaret/Pekka
Margaret reviewed the status of the v6ops projects and various
activities (see the v6ops web sites and slides above).
UNMAN Analysis discussion - Christian Huitema
Christian presented on the Unmanaged Network Analysis draft (see slides and
draft above) ending with a summary of his recommendations:
Develop and standardize Teredo or similar technology
Agree on standardized IPv6 prefix delegation mechanism
For "informal prefix sharing", develop a standard way to perform "RA
proxy", possibly as part of a "multi-link subnet" specification
Standardize a way to provision a DNS resolver address in IPv6 only hosts
Proceed with the standardization of LLMNR
Continue standardization of 6to4
Standardize an IPv4 over IPv6 tunneling mechanism, as well as the
associated configuration services
Christian believes the next steps are to:
WG last call for evaluation document
Act on recommendations
Rob Austein said that, as a design team member, he didn't remember
Alain Durand felt that the scope of the document is not to recommend
specific technology, e.g., teredo, rather to point out there are holes in
IETF specifications that need filling.
Erik Nordmark asked why prefix delegation isn't sufficient? Why is RA
proxy also needed?
The chairs noted that this item should be taken to the list, and v6ops may
not be the right place to decide.
Margaret noted the lack of mailing list feedback on the draft.
Erik Nordmark asked if the decision for IPv6 over NATed networks should be
Margaret felt that there should be an interim meeting for this issue.
Tim Chown asked why 6to4 was proposed instead of tunnel brokers?
Christian replied because 6to4 does not need much configuration nor a
Tim noted that the tunnel broker user experience seems to be more
Marc Blanchet felt that the tunnel broker does not get a fair chance in the
analysis draft. Christian replied that there has not been enough time to
incorporated the tunnel broker work.
Marc asked if he committed to add the tunnel broker to the analysis
draft, to which Christian replied that he was only making a
commitment to discuss and evaluate.
Erik Nordmark noted that there is tension between configuration and
no-configuration solutions. Too much automation may be bad as it is
difficult to debug. This has not been sufficiently discussed.
Christian replied that there has to be a way out of the automatic
mechanism if it fails.
Marc Blanchet noted that the freenet6 tunnel broker proposal has never been
given a chance to be reviewed, which he felt was unfair.
Tony Hain said that the discussion is not in the right context here. This is
not a problem for unmanaged networks but for enterprise networks.
Bill Sommerfeld asked why is it that the security implications are just for
v6 and not for v4. Christian noted that v4 is often behind NATs and thus a
little bit more protected.
Bill replied that this was not true. However, he will send the text to
Christian to explain what is needed to change in the text.
Rob Austein stated that help is needed for the analysis document. It is
still fairly new, and does still need work.
Margaret noted that while the scenarios draft has been sent to the IESG, the
analysis draft still needs work. She then asked how many people have read
the doc, noting that she didn't see many hands, and that people should read
and comment on the draft.
Forwarding Protocol 41 in NAT Boxes - Jordi Palet
Jordi Palet presented his draft on forwarding protocol 41 in NAT boxes (see
draft and slides above). The basic premise is that this behavior is not
documented, though it is widely used. Jordi noted that there is no need for a
new transition mechanism.
Christian Huitema commented that he had looked at this approach a few
years ago. However, it does not scale beyond one computer behind the NAT.
Jordi replied that it isn't intended to be a general solution, and may not be
the right for a totally unmanaged network. There may have to be a PC based
router behind the NAT.
Christian noted that though it does work in very restricted cases, it
isn't really applicable to unmanaged networks.
Pekka Savola commented that it is clear that it does not work for many
Rob Austein also thought that here are already applications like this.
Bob Hinden felt it would be better to recommend that they have v6 in the
Keith Moore (through Jabber) commented that he thought it better to have
6to4 in the NAT.
Tim Chown noted that this solution could be added to the current NATs as a
simple firmware update.
Christian said that there are many NAT vendors are implementing 6to4 in the
NAT. It is actually bad to recommend the protocol 41 as you will confuse the
Jordi felt that this could be a possible "second choice" for NAT
Itojun stated that this should not be recommended, but this current
practice should be documented.
Alain Durand asked if this solution is compatible with 6to4 in the NAT box?
Christian replied no.
The chairs felt that there should be more discussion on the list as to what
should be done about this document.
IPv6-IPv4 Translators in 3GPP Networks - Karim El-Malki
Karim El-Malki presented his IPv6-IPv4 Translators in 3GPP Networks draft
(see draft and slides above).
Someone commented that STUN doesn't work the way Karim proposed.
Gonzalo Camarillo commented that the Sipping WG has worked more on v4 and
NAT. v6ops has the knowledge on v6ops. There is no place to start the
Margaret stated that it may be better to have this in the sipping wg as it
raises the v6 awareness there, and to give support there for IPv6.
Peter noted that the NAT-PT part could be useful.
Margaret asked what is the relation of this and the 3GPP analysis
document? Jonne Soininen replied that the analysis document hints that
something is needed, but the actual solution has not been done there.
What action, if any, is needed next?
ISP Scenarios - Mikael Lind
Mikael Lind presented the ISP Scenarios team's draft (see draft and
slides above), noting that the team had started over with new draft, an
that it was a further simplification of the arlier team effort.
It defines a generic ISP network and stages of maturity, with
transitions between stages, but was limited in detail, omitting v6-only
Dave Meyer asked how sensitive is the analysis? He noted that there is some
movement to collapse edge-to-core networks. Mikael noted that the team was
talking about DSL modems, etc, not real access routers. That the focus was on
ISPs, not all coexistence mechanisms, and asked if the team should write a
guide for ISPs, i.e., refocus the intent of the documents.
Alain Durand asked if we can really design a generic network? We have
already deployed IPv6 in some networks - should we document what they did?
Mikael replied that although people have deployed, have they deployed in
- Should we talk about different kinds of networks (DSL, cable, etc.)? how to
transition my IGP?
- Should we end this work? Is there enough ISP interest to justify the
Pekka Savola noted that it was very simple and general at this point - is
that OK? Is it sufficient?
Margaret asked to hear from ISPs?
Kurt Lindqvist commented that ISPs differ a lot. How many ISPs have
deployed v6 with same SLAs as v4?
Dave Meyer noted that this is the same as MSDP - go document the
problems people were having in deployment instead of doing a
comprehensive guide of all possible scenarios.
Shin Miyakawa noted that it is difficult to define transition path for the
NTT backbone, that they can think about anything, but
administration may limit them. Some routers can do what we want, others
can't. Eventually this will change. Some parts of network are SONET, some
are MPLS - there are lots of technologies inside our networks!
Carl Yeager said that from his ISP point of view, we need a lot more
details about the applications required for the transition. Document is
nice but doesn't help small ISP migrate. Should this happen at NANOG or
similar? It's a FAQ, not an RFC... that this is more like a tutorial on
IPv6 than an ISP document - not sure that's what we need.
Brian Carpenter commented that we did this to find out if we were
missing any transition mechanisms. Margaret further noted that we need to
know how operators will actually deploy v6. Pekka felt that our charter
does include documenting operational practice.
Margaret asked how many ISPs think v6ops should do this work? There was
some support shown.
How many are willing to help us? Some.
How many people have read the draft? Some.
How many people are ISPs in the room? Quite a few.
How many can help? Some.
The chairs asked for interested ISP folk to come to them after the
meeting and volunteer.
ENT Scenarios - Yanick Pouffary/Jim Bound
Yanick Pouffary presented an overview of the Enterprise Scenarios draft
(see draft and slides above). She especially noted that there had been much
recent reworking of the draft to accommodateds team input and that the team
now felt that it was time for it to be accepted as a wg draft.
Also of special note was that 3 base scenarios are defined to capture the
essential abstraction set for the Enterprise. That it should be noted
There are definitively more scenarios
We cannot possibly cover all of them
We selected the most representative ones
Yanick also said that the team will write a revision to the scenarios
document for the next IETF, that there is still work to do on this
scenarios doc but we need to hear from the wg on the mail list. She also
thanked Alain Durand who has given input.
Yanick finished by noting that the team will start on a new analysis
document to map relevant transition mechanisms to the base scenarios.
Brian Carpenter stated that more progress will be made if it's a working
group document. Need to think about security boundaries, etc.
Christian Huitema noted his concern that we will have a very unwieldy
document because things are combinatorial. Margaret noted that the team is
trying to simplify.
Alain Durand noted that it's a framework, and that it doesn't have to
cover all cases.
Bob Hinden commented that we're doing scenarios to flesh out
transition mechanisms, and don't have to have all possible scenarios.
Margaret asked for hands on supporting this document as a wg draft. There
was unanimous support to accept this as WG document.
Second Session: Wednesday, July 16, 2003 at 1530-1730
v6-on-by-default - Alain Durand
Alain Durand presented the draft on actual experiments of IPv6 on by
default work at Sun (see draft and slides above).
we come from a world where breaking existing technology (v4) when
introducing new technology (v6) is not something we like
partial ipv6 deployment in our network
6to4 based, no relay router, no isatap
some subnets are v6 enabled, some not
some v4 subnets use private address
some access to the enterprise network are through ipv4-only VPNs
v6 addr are published into internal dns
took 3 well-known implementations with ipv6 turned on
observe interesting characteristics in bad v6 connectivity, private
address, and stuff
measure time it took to fall back from one address to the other
extremely high delay on one of the 3 implementation
"when you don't have a router, assume destination is onlink"
"no RA" case should be "zero delay" -> "onlink" assumption
tcp timeout assumptions
use v6-aware vpn, if not: tcp timeout delays
v6 packet may go to unexpected path (non-vpn side)
Rob Austein noted that TCP for v6 was a mess - no difference between v4 and
Itojun noted that "no RA" case -> ambiguous about outgoing interface, ND
spec need clarification
Erik Nordmark noted that the onlink rule is useful when RA prefix is
expired but address is not expired.
Pekka stated that need to analyze pros and cons.
In cases of incomplete v6 connectivity, VERY long delays on some
implementations (in one case, 225 seconds before route change, even with
ICMP and RA) ? and this is per-address-tried!?! No reason it should even be
25 seconds ? need to tweak the spec so timeout is almost zero.
Use AAAA in your DNS with caution!
Use v6-aware VPN, if not (1) TCP timeouts, (2) packets don't go where you
think, (3) VPN should intercept/sink v6 packets.
Other issues are less critical, but please read draft.
Rob Austein noted that this is good work; we definitely need to write this
down. Most of these failures were also encountered in v4. We're more
likely to have lots of addresses in v6, so the problem is worse in v6.
Itojun commented that the ND specification assumes every destination is on
link, but is not clear when it is not the case. This part of the spec
could be clarified.
Mohsen Souiss noted that every TCP-based application does not work the same
way. For example, some web browsers are stuck on IPv6 addresses and this is a
bad thing. Alain Durand replied that Telnet actually is using the API the
way it should be used.
Mohsen noted that with dig, for example, we get stuck as well. Some
application should be.
Pekka Savola noted that it is clear that the application should not be
Alain: commented that issue 1 related to RFC2461 really hurts and should be
fixed. The fix is necessary to ship product.
Margaret asked if the wg should take this on as a WG item. There was
unanimous support for this.
Moreover, Margaret, as co-chair of the ipv6 WG, thinks this will result in
threedegrees - Christian Huitema
Christian Huitema presented an update on the Threedegrees work he has
previously presented last year in v6ops.
Main issue is that there are DNS issues in the Threedegrees
deployment. Some DNS responders respond with very bad responses, but these
vendors have been contacted and fixes are coming.
The DNS issue has been documented for the dnsop WG, in
Security - discussion of what we should be doing - Chairs
Pekka Savola presented his security overview draft (see draft and slides
above) to facilitate a discussion on what v6ops should be doing on
security. This discussion was scheduled as security is a core part of the
charter of v6ops, and there is a need to decide what to do to address this
Look at different kinds of issues
Transition mechanisms in general
+ general observations
What should we do about it?
Very prominent in the charter, something needs to be done
An abstract approach
Which drafts would be applicable/which work should be initiated
Adopt some drafts / initiate some new work?
Different kinds of issues (the IPv6 protocol suite)
Protocol itself (some generic, some more specific)
Some people afraid of increased end-to-end transparency
people used to the NAT "security model"
education required; need a mechanism to control access
Some people afraid of increased end-to-end encryption
people used to the perimeter firewall "security model"
due to key mgmt difficulties, may not be a huge problem
highlights the need for end-host, distributed, managed
Issues in specifications
how hosts should parse Routing Headers
how privacy addresses' applicability is not clear
how ICMPv6 messages may be generated in response to multicast
how neighbor discovery "on-link" sending model causes
Different kinds of issues (transition)
Tunneling in general
UDP tunneling typically punches through NATs *AND* firewalls;
configured IPv6-in-IPv4 tunneling slightly better (typically
Automatic tunneling mechanisms
the risks of packet forgery and DoS attacks increase
the virtual topologies, especially ad-hoc ones, make the network
architecture more complex
communication with third parties in automatic tunneling
unless carefully done, increases the risk of DoS etc.
Different kinds of issues (deployment)
Issues in deployment
Problems with IPv4/6 dual stack use
certain cases of deployment may incur large timeouts (as
quality of IPv6 routing globally is inferior to IPv4: worse
some applications don't handle all the fallbacks properly
some DNS servers/load-balancers abuse AAAA-querying resolvers
Insecure service piloting
testing services/applications without proper access controls
Operational factors in network infrastructure
unstable(r) router software, causing virtual topologies or breaks for
slower processing (non-line-speed), causing hacks like MPLS
missing features (e.g. no ability to turn off IPv6 telnet access)
insecure default configuration/assumptions (if IPv4 access is
restricted, IPv6 may be allowed by
default unless explicitly disallowed)
costs of running one protocol (multiple topologies) vs two
protocols (double the processing)
Different kinds of issues
Things to note in general
Prefer native IPv4/IPv6
security issues greatly simplified
Accept configured tunneling
plain and simple
where necessary, try to avoid if possible
explicit knowledge of the end-points: a lot fewer risks
Avoid automatic tunneling
security properties typically difficult to handle
usually bring on a lot of complexity
may be difficult to retire ("sunset strategy")
What should we do about security?
Charter lists a lot of items of IPv4/IPv6 operations
1. solicit input on sec issues from operators/community
2. provide feedback to IPv6 WG on specs which are likely
to cause sec issues
4. publish docs on security risks of the operations (w/ sec area)
5. identify sec issues in deployment scenarios/solutions
We had better DO something!
Security is about the most important item on our charter
But what to do?
What should we do about security (generic)?
We need more security expertise
To evaluate security aspects of the proposals from the first
And to help in figuring out an answer to the all of below
We need better idea how to evaluate security
How to deal with issues transparency etc. imply?
specify local access control mechanisms?
try to see if there's work on end-host firewalling?
How to deal with issues NAT/firewall traversal imply?
do we need to do more than what other NAT traversal mechanisms have
probably yes, but what?
How to deal with the evaluation of transition mechanisms?
how much complexity is "too much"?
how much security is "enough"?
What should we do about security (concrete)?
Current drafts which could be applicable to this WG
something like this is very much in scope
Adopt some of the previous drafts?
If not adapt, push for being worked on (security area? IPv6 wg?)
Should we start working on something new?
Bring in that security input from the ops/users community!
How to go about those issues in IPv6 specs?
Need to create two documents on security? *ARE* there issues to
(ch4): potential security risks in the operation of
(ch6): identify open sec issues with deployment scenarios?
If so, maybe need a small editorial team (or DT).
There seemed to be a number of security people in the room for the
discuss that follows.
Itojun: Agreed with overall direction of this document. 6to4 relay is his
hot issue, and he is still interested in getting his document
Rob Austein: tried to work on these issues at IAB workshop last year ?
could dig this up again. Pekka and I are converging offline, on a
semi-configured tunnel that's easier to use than existing proposals.
Margaret: How do we get "significant study"? IRTF research group?
Rob: talk to Bellovin.
Christian Huitema: analysis should take place. Lots of proposals to limit
impact of "automatic tunneling". You exaggerate the danger of 6to4
relays. Source spoofing attacks happen today, other dangers are worse.
Randy Bush: security threats are best addressed by updating an existing
document. Randy noted that he disagreed with Christian.
Erik Nordmark: the WG is supposed to be looking at 6to4 security.
Operators can look at the document and assess risks.
Pekka: Not significantly worse than the v4 Internet today.
Alain: Pekka's 6to4 document is already good. Make it a WG item and
last-call it, move forward.
Brian Carpenter: Pekka did a good job. Don't think there's much we can
change in 6to4 without abolishing it.
Margaret: Enough recent readers to make decision on making Pekka's draft a WG
Randy: it's an analysis of a WG protocol ? how much debate do we need?
There was a unanimous show of hands to accept Pekka's draft as s WG
Gregory (security product vendor): We've been talking about NAT
security a lot at my company. The world believes this, no matter whether we
believe it or not. NAT default is nothing flows, v6 default is
everything flows. Are we building walls or roads here?
Someone asked how hard is it to establish inside-to-outside
initiation as a default? Any vendor can do this today.
Margaret: "How difficult could it be" for someone configuring routers in
their home? Impossible. Can vendors pre-configure all of this?
Bob Hinden: not hard to start firewall with restrictive set of rules.
Tony Hain: we're talking about security, and NAT doesn't equal
security. If you're going to replace a filtering device, you probably want to
replace it with another filtering device.
Gregory: Stateful inspection is hardest at application gateway level,
especially with dynamic ports. Can we define this, or make
application guys define this (via registry)? Then Mom could do this
Margaret: this is more than we can do here.
Christian: this is v6ops, not NATops. What we have to preserve is the
security of the users, and there are many ways to accomplish this (host
Matt: how to move forward? Divide-and-conquer with small documents doing
threat analysis? Don't do an 80-page document!
Alain Durand: one thing we've observed is that we need to make sure v4 and v6
security policy provide the same security. We need tools to make sure two
policies match, including update frequency.
Rob Austein: two ways to protect Mom. Mom outsources this to an ISP, or UI on
the box that Mom buys. This is a challenge for UI and application behind UI,
and needs to be updated whenever a new application comes out.
Gregory: what we need to preserve is NATish isolation, not NAT itself.
Magaret: ADs should say how to figure out this issue.
NAT-PT Applicability Statement team report - Peter Barany
<no draft yet>
Peter Barany presented a report from the new NAT-PT Applicability
At the IETF V6OPS WG meeting in San Francisco, CA (IETF #56 meeting)
Discussion took place about status of standards track RFCs
NAT-PT/SIIT (2766/2765) (just sitting at PS)
No active editor for NAT-PT
Need to decide what to do by March 03 with NAT-PT/SIIT
Write an Applicability Statement?
Decision: Write an Applicability Statement
Form a Design Team
Design Team Members
Suresh Satapati (Design Team Lead)
NAT-PT Applicability Statement
No Internet draft available yet.
Scope & Goals
Document the applicability (or non-applicability) of NAT-PT
See RFC 2026 for definition of Applicability Statement
Proposing modifications to NAT-PT (RFC 2766) (or extensions to make
is not within the scope of the Design Team
"Table of Contents
2.1 Deployment Scenarios
3. Security Considerations
5. Authors and Contact Information
6. Full Copyright Statement
For 2.1 - Deployment scenarios agreed upon by Design Team
2.1.1 3GPP Networks
2.1.2 Futuristic Scenario
Entire network infrastructure is IPv6 but there are some existing IPv6
hosts (or applications) that cannot be upgraded
For 2.2 - Limitations
Applications with IP addresses embedded in payload
Single point of failure
Question about SIIT: do we want to also include SIIT? Should it be
considered, as well as NAT-PT? Same question with
Margaret: OK to work on theses RFCs as well.
The Design Team has a mandate to include SIIT (RFC 2765) in the NAT-PT
Applicability Statement document (not sure whether or not we have to
change the title of the document to reflect this). Where SIIT is
referenced by RFCs/I-Ds other than NAT-PT (e.g., RFC 2767 BIS), a
separate section should/can be included in the NAT-PT
Applicability Statement document discussing SIIT in this context.
Christian: you listed NAT-PT scenarios, but we found scenarios where
NAT-PT should NOT be deployed ? these should be included as well.
Applicability statements can be negative ? "don't use this here".
Marc Blanchet: think about ICMP! Troubleshooting or something, but it's an
Alain: SIIT depends on where translation is happening. Pekka: some
confusion about what "ICMP" really is ? SIIT is not usually used on its
Rob Austein ? Most of the experience we have with SIIT was from NAT-PT. I
wish I could forget ICMP.
Peter Barany remarked that this would be handled/discussed most likely in
the SIIT portion of the NAT-PT Applicability Statement document (as it
relates to NAT-PT ... not BIS). ICMPv6 translation is discussed in detail in
RFC 2765 (also, some of this will necessarily spill over into
mobility/MIPv6 discussed since MIPv6 uses extensions to ICMPv6 ... as do
other IPv6 technologies, e.g., multicast). We need to think about how to
partition the document to handle ICMPv6 and SIIT.
It was also noted that the Design Team should think about using the
Cellular Networks, Unmanaged Networks, ISP Networks, and Enterprise
Networks as possible scenario sub-sections in the NAT-PT
Applicability Statement document since these scenarios are already being
addressed in separate I-Ds by the appropriate Design Teams and the work on
NAT-PT could be re-used from those 4 Design Teams. Peter said that the
design team will look at this.
Margaret: agreement of the WG to make this work a WG item will be taken on
the list when the first draft is available.
Writing IPv6 Applications report - Myung-ki Shin & Pekka Savola
Myung-ki Shin presented the newest version of his application
transition draft (see draft and slides above).
Why this draft:
As IPv6 is deployed, the application developers and the
administrators will face several problems
clarifies the problems and considerations
application transition scenarios (cases)
proposes guidelines on developing IP version-independent
One of the charter items of this wg
good starting point for this topic
General Problems with IPv6 application transition
Dual-stack vs. application versions
Operating system being dual stack does not mean having both IPv4 and
DNS name resolution
A client application can not know the version of peer
application by only doing a DNS name lookup
Users may be confused by their various application versions
(IPv4-only, IPv6-only, IPv4/IPv6) because they don't know the version of
peer application by DNS query results
Application porting considerations
"IP version dependencies in applications
Presentation format for an IP address
dotted-decimal string for IPv4 vs. hexadecimal string for IPv6
Transport layer API
functions to establish communications and to exchange
Name and address resolution
conversion functions b/w hostnames and IP addresses
Specific IP dependencies
IP address selection, application framing, storage of IP addresses
Developing IP version-independent applications
In order to allow applications to communicate with other IPv6 nodes, the
first priority is to convert the applications supporting both IPv4 and IPv6
IP version-independent structures & APIs
The applications should do iterated jobs for finding the working
address out of addresses returned by getaddrinfo()
The applications will have to work properly in IPv4-only nodes
(whether IPv6 protocol is completely disabled)
Transition mechanism considerations
Handling NAT-PT(DNS-ALG) address prefix
Any other mechanisms ?
Handling IPv4 mapped IPv6-addresses
Applications Area persons will join this team (as of Open Apps Area
meeting on Monday).
Margaret: GRID people want to contribute, too.
Dual-stack doesn't mean clients have both v4 and v6 applications.
DNS does not know the version of an application based on DNS lookup.
Looking at v4 applications in dual-stack, then v6 applications in
Dual-stack applications on v4-only host ? EPROTONOSUPPORT or
EAPNOSUPPORT errors dump out of the socket loop, and v4 is never tried!
Presentation format, transport API, naming and addressing...
Several guidelines on developing IP version-independent
applications, including running in v4-only nodes.
Security considerations ? v4-mapped v6 addresses.
Pekka: comments from Apps AD ? address being overloaded as identifier ?
needs to be clarified in this document.
Q: failure of v6 address and fall-back to v4? Preference based on
performance, not just being v6? Alain: this is no different from
Q: with default address selection, we could override v6 preference choice to
Brian: is this going to be a generic I/O system? Brian is almost-WG chair in
Global GRID forum. Need to figure out how to work together.
Q: v6-only? If you use v6 APIs, you have access to v4 addresses in v6
Christian: one may want to develop v6 only app because of NAT
Alain: don't want to ship one app for each case.
Patrik: What do you mean by "application"? "GETHOSTBYNAME" is all I want to
do (multiple interfaces, etc. are things I'd like to ignore)...
Discussion is strange...
Margaret: you're saying document deals with useful issues, but how many are
applicable to applications writers?
Q: Are C libraries the kind of applications we're talking about? Connect
serially or in parallel? Margaret: DNS is an application, and TCP is on the
hairy edge of being an application.
The document will be revised with the help of applications people, and will
come back to v6ops later.
Status report of IPv4 Survey drafts - Chairs
Pekka gave a status report of the progress of the IPv4 Survey
individual drafts since the last IETF (see drafts above).
Pekka said that he and Margaret had pinged the appropriate ADs since
IETF-56, and got responses from about four areas, and also met with the
APPS area at this meeting. The nine documents now have individual
editors assigned to each.
Documents will be updated after the first round of comments received from
the areas. The co-chairs will follow up with other areas not yet heard
Pekka noted that these documents need to be credible ? so all wg
participants are requested to review them!
There were no comments.