Did you have any editorial comments?

All I'm finding are (continued) disputes about content.

Tony


On Jul 31, 2010, at 8:21 PM, Robin Whittle wrote:

> Short version:   Draft 09 of the Report contains omissions and
>                 misleading statements concerning Core-Edge
>                 Elimination architectures in general and ILNP
>                 in particular.
> 
> 
> Hi Tony,
> 
> In the ILNP summary is the text:
> 
>  ILNP can be implemented such that existing applications (e.g.
>  applications using the BSD Sockets API) do NOT need any changes or
>  modifications to use ILNP.
> 
> I spent a day and a half trying to figure out how ILNPv6 could
> support existing IPv6 applications - and I decided tentatively that
> it couldn't be done.  Ran hasn't responded to my messages on this,
> but you did - and you couldn't come up with a way of making it work
> either:
> 
>   ILNP: stack behavior to work with IPv6 apps?
>   http://www.ietf.org/mail-archive/web/rrg/current/msg07108.html
> 
> and 4 more messages in that thread.
> 
> The Critique assumes that ILNP can work with IPv6 applications -
> although it notes that IP-address referrals won't work without
> "additional mechanisms".  In practice, this means that some or many
> IPv6 applications can't work with ILNP.
> 
> However, my attempt to see how ILNP would support IPv6 application
> ran into trouble even without considering IP address referrals.  A
> major difficulty was that when the app asks the stack to look up an
> IP address, what does the stack give the app?  All attempts to figure
> this out, by you and me, lead to outcomes which were clearly not
> going to support IPv6 applications.
> 
> So I think the ILNP Summary as it stands contains a significant false
> claim which is not tackled in the Critique.
> 
> Also, regarding ILNP, your Recommendation includes:
> 
>   It separates location from identity in a clear,
>   straightforward way that is consistent with the
>   remainder of the Internet architecture and makes
>   both first-class citizens.
> 
> This is not true with ILNP mobility, since when the host roams to
> another /64, there is no way of ensuring that some other host hasn't
> already taken the IP address there with this hosts ID bits in the
> lower 64 bits.   This has been extensively discussed in the threads:
> 
>   ILNPv6 Mobility problem
>   ILNP Identifier and Locator semantics are muddled and !crisp
>   ILNP Identifiers are not "first class citizens"
>   ILNPv6 Mobility problem (attempt at summary)
>   ILNPv6 Mobility - ILNP can't work with SEND (AFAIK)
> 
> ILNP mobility is subject to an "Identifier squatting" DoS attack,
> which is easy to launch (look up the victim's FQDN and get its ID) by
> the attacking host behaving in a manner which is indistinguishable to
> the network from proper behaviour of any IPv6 or ILNP host.
> 
> Also, the Report doesn't distinguish between ILNPv6 and ILNPv4.
> ILNPv4 makes all packets longer, and can only be introduced at all
> once most or all DFZ and other routers have been upgraded.
> 
> For instance, in the Summary:
> 
>    Locators name subnetworks, rather than interfaces, so they
>    are equivalent to an IP routing prefix.
> 
> is only true of ILNPv6.
> 
> Reading the Report as it stands, one might think:
> 
>  ILNP is for IPv4 and IPv6.
> 
>  ILNP doesn't require any changes to routers.
> 
>  ILNP mobility has no particular weaknesses specific to ILNP.
> 
>  ILNP supports existing applications.
> 
> 
> But for ILNPv6:
> 
>  All applications must be rewritten.  (This places a huge
>  additional burden on those who try to test ILNP - they
>  will need to get a bunch of open-source apps and significantly
>  rewrite them - and this may break the application's on-the-wire
>  protocols.)
> 
>  Mobility is not robust against a simple DoS attack, or against
>  a chance situation where the ID in the new /64 is already taken.
> 
> In addition, for ILNPv4:
> 
>  Most or all DFZ and other routers need to be upgraded before
>  any ILNP hosts can communicate over the IPv4 Internet.
> 
> 
> The Critique fails to capture two other objections to ILNP and other
> CEE architectures:
> 
>  1 - They typically involve extra packets being sent and received
>      by hosts (such as for DNS lookups) and so extra delays in the
>      establishment of communications.
> 
>      For instance, A looks up B and sends B a packet.  If B's
>      application needs to ensure its reply can only go to A, then
>      B needs to find A's FQDN (AFAIK, by relying on reverse DNS
>      lookup of A's IP address returning the FQDN) and then do a
>      lookup of that FQDN to get A's Locator.  B cannot trust the
>      Locator which came with A's initial packet since that
>      packet could contain a locator not of the real A, but of a
>      network where the attacker's machine has A's ID.
> 
>      Some applications don't actually need to do this, so if the
>      applications are rewritten for ILNP, this will be less of a
>      problem.  However, if ILNP is to support IPv6 applications,
>      the stack in B needs to do these lookups before it can send
>      B's application's reply packet - since IPv4/6 applications
>      are written on the assumption that the routing system will
>      never deliver a packet to a host with an Identity different
>      from that of the packet's destination address.
> 
>      These DNS lookups take time.  They may involve intermediate
>      lookups too.
> 
>      These delays to establishing communications, and the extra
>      packets are particularly onerous for devices on 3G etc,
>      wireless links which involve delays, costs, lost packets and
>      bandwidth restrictions which are worse than what most of us
>      are used to at home via a DSL service.
> 
>  2 - Substantial benefits to scalable routing and to anyone who
>      adopts ILNP (or any other CEE architecture) only arise once
>      all, or virtually all, hosts adopt it.  This is covered in:
> 
>        http://www.firstpr.com.au/ip/ivip/RRG-2009/constraints/
> 
>      and so involves much greater hurdles to widespread adoption,
>      while also requiring almost ubiquitous adoption before there
>      can be substantial benefits.  Until all hosts (and so I think
>      all apps) are upgraded, a significant proportion of
>      communications will still rely on the old IPv4 or IPv6 system
>      - so multihoming and mobility won't work for all
>      communications.  Until then, networks will still want and need
>      PI space to support the old style of communications.
> 
> 
> With these omissions, and the false statements about ILNP, the 09
> draft fails to inform readers of the major problems with CEE
> architectures in general, and with some problems which are specific
> to ILNP.
> 
>  - Robin
> 
> 

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