Info & FAQ |  Resource services |  Training |  Meetings |  Membership |  Documents |  Whois & Search |  Internet community

You're here:  Home  Mailing Lists sig-policy 

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[sig-policy] New version of prop-110: Designate as Anycast to support DNS Infrastructure

Dear SIG members

A new version of the proposal "prop-110: Designate as Anycast 
to support DNS Infrastructure" has been sent to the Policy SIG for review.

Information about earlier versions is available from:

You are encouraged to express your views on the proposal:

- Do you support or oppose this proposal? 
- Is there anything in the proposal that is not clear? 
- What changes could be made to this proposal to make it more effective?



prop-110v002: Designate as Anycast to support DNS

Proposers:       Dean Pemberton, dean@internetnz.net.nz
                 Geoff Huston, gih@apnic.net

1. Problem statement

   Network 1 ( was allocated to APNIC by the IANA on 19
   January 2010. In line with standard practice APNIC's Resource Quality
   Assurance activities determined that 95% of the address space would
   be suitable for delegation as it was found to be relatively free of
   unwanted traffic [1].

   Testing, conducted by APNIC R&D found that certain blocks within
   Network 1 attract significant amounts of unwanted traffic, primarily
   due to its unauthorised use as private address space [2].

   Analysis revealed that, prior to any delegations being made from the
   block, attracted an average of 140Mbps - 160Mbps of
   unsolicited incoming traffic as a continuous sustained traffic level,
   with peak bursts of over 800Mbps.

   The analysis highlighted individual addresses such as with
   its covering /24 (identified as remain in APNIC
   quarantine and it is believed they will not be suitable for normal
   address distribution.

   The proposal proposes the use of in a context of locally
   scoped infrastructure support for DNS resolvers.

2. Objective of policy change

   As the addresses attract extremely high levels of unsolicited
   incoming traffic, the block has been withheld from allocation and
   periodically checked to determine if the incoming traffic profile has
   altered. None has been observed to date. After four years, it now
   seems unlikely there will ever be any change in the incoming traffic

   The objective of this proposal is to permit the use as a
   anycast addresses to be used in context of scoped routing to support
   the deployment of DNS resolvers. It is noted that as long as
   providers who use this address use basic route scope limitations, the
   side effect of large volumes of unsolicited incoming traffic would
   be, to some extent mitigated down to manageable levels.

3. Situation in other regions

   Improper use of this address space is a globally common issue.
   However the block is delegated only APNIC and so therefor, no other
   RIR has equivalent policy to deal with the situation.

4. Proposed policy solution

   This proposal recommends that the APNIC community agree to assign to the APNIC Secretariat for use in the context of locally
   scoped infrastructure support for DNS resolvers.

   At some future point there is nothing restricting an RFC being
   written to include this prefix into the special-purpose IPv4
   registry.  However, at this time it is considered sufficient for the
   APNIC community to designate this prefix to be managed as a common
   anycast address for locally scoped infrastructure support for DNS

5. Advantages / Disadvantages


   - It will make use of this otherwise unusable address space.
   - DNS operators will have an easy-to-remember address they can use to
     communicate with their users (e.g. configure "" as your DNS


   - The address attracts a large volume of unsolicited incoming
     traffic, and leakage of an anycast advertisement outside of a
     limited local scope may impact on the integrity of the DNS service
     located at the point associated with the scope leakage. Some
     operators with high capacity infrastructure may see this as a
     negligible issue.

6. Impact on APNIC

   Although this space will no longer be available for use by a single
   APNIC/NIR account holder, the proposal would result in benefit for
   all APNIC community members, as well as the communities in other


   [1] Resource Quality Good for Most of IPv4 Network "1"

   [2] Traffic in Network