Subject: draft-yhb-6man-ra-privacy-flag-02

From: "Yu Hua bing" <[email-masked]>
Date: Wed, 16 Mar 2011 21:48:11 +0800

Hi, please read the following words.After you read the words, you may agree that the DisablePrivacy flag is helpful.

RFC 4941

3.6.  Deployment Considerations

   Devices implementing this specification MUST provide a way for the
   end user to explicitly enable or disable the use of temporary
   addresses.  In addition, a site might wish to disable the use of
   temporary addresses in order to simplify network debugging and
   operations.  Consequently, implementations SHOULD provide a way for
   trusted system administrators to enable or disable the use of
   temporary addresses.

   Additionally, sites might wish to selectively enable or disable the
   use of temporary addresses for some prefixes.  For example, a site
   might wish to disable temporary address generation for "Unique local"
   [ULA] prefixes while still generating temporary addresses for all
   other global prefixes.  Another site might wish to enable temporary
   address generation only for the prefixes 2001::/16 and 2002::/16,
   while disabling it for all other prefixes.  To support this behavior,
   implementations SHOULD provide a way to enable and disable generation
   of temporary addresses for specific prefix subranges.  This per-
   prefix setting SHOULD override the global settings on the node with
   respect to the specified prefix subranges.  Note that the pre-prefix
   setting can be applied at any granularity, and not necessarily on a
   per-subnet basis.

   The use of temporary addresses may cause unexpected difficulties with
   some applications.  As described below, some servers refuse to accept
   communications from clients for which they cannot map the IP address
   into a DNS name.  In addition, some applications may not behave
   robustly if temporary addresses are used and an address expires
   before the application has terminated, or if it opens multiple
   sessions, but expects them to all use the same addresses.
   Consequently, the use of temporary addresses SHOULD be disabled by
   default in order to minimize potential disruptions.  Individual
   applications, which have specific knowledge about the normal duration
   of connections, MAY override this as appropriate.