Subject: rfc4941bis: Change to Valid Lifetime of temporary addresses

From: Fernando Gont <[email-masked]>
Date: Thu, 30 Jan 2020 19:27:25 -0300

Folks,

It has been suggested by Lorenzo Colitti, David Farmer, and others, to 
change the default Valid Lifetime of temporary addresses.

Namely, to change it from the current (RFC4941) "one week", to "two 
days". This indirectly limits the maximum number of temporary addresses 
employed by hosts. (2, compared to the current 11 (as per RFC4941)).

This requires these changes:

* Section 3.5:

OLD:
    Because the precise frequency at which it is appropriate to generate
    new addresses varies from one environment to another, implementations
    SHOULD provide end users with the ability to change the frequency at
    which addresses are regenerated.  The default value is given in
    TEMP_PREFERRED_LIFETIME and is one day.  In addition, the exact time
    at which to invalidate a temporary address depends on how
    applications are used by end users.  Thus, the suggested default
    value of one week (TEMP_VALID_LIFETIME) may not be appropriate in all
    environments.  Implementations SHOULD provide end users with the
    ability to override both of these default values.

NEW:
    Because the precise frequency at which it is appropriate to generate
    new addresses varies from one environment to another, implementations
    SHOULD provide end users with the ability to change the frequency at
    which addresses are regenerated.  The default value is given in
    TEMP_PREFERRED_LIFETIME and is one day.  In addition, the exact time
    at which to invalidate a temporary address depends on how
    applications are used by end users.  Thus, the suggested default
    value of two days (TEMP_VALID_LIFETIME) may not be appropriate in all
    environments.  Implementations SHOULD provide end users with the
    ability to override both of these default values.

* Section 5:

OLD:
    TEMP_VALID_LIFETIME -- Default value: 1 week.  Users should be able
    to override the default value.

NEW:
    TEMP_VALID_LIFETIME -- Default value: two days.  Users should be able
    to override the default value.

Comments? Objections?

Thanks!

Cheers,
-- 
Fernando Gont
SI6 Networks
e-mail: [email-masked]
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492