PGP bet practices when key expires?

[alex at pennace.org (Alex Pennace)]

On Fri, Sep 01, 2006 at 11:13:22AM -0400, V. Alex Brennen wrote:
> Yes.  However, it would have been best practice to generate a new key 
> pair before the old key pair expired.  Then, to use the old key pair
> to sign the new key pair there by linking it into the web of trust.
> 
> After doing that, you could have mailed all of the people who signed 
> your old key in the past requesting that they sign the new key.  Upon
> receiving a note with a signature from a key that they explicitly trust,
> or with a signature from a key signed by a key that they explicitly 
> trust, they should be willing to trust the new key enough to sign it.
> 
> There is nothing inherently wrong with extending the key's expiration
> date. But, I think that before some one does that they should
> themselves - "What has changed about the threat model that I now trust
> this key to be valid for a longer period of time than I did when I first
> generated  it?"  Historically, cryptographic algorithms, protocols, and 
> systems have always gotten easier to break over time. 
> 
> Additionally, it's beneficial to change keys every few years because
> if a key is ever compromised only the signatures for a limited amount
> of time are compromised.  The compromise is limited to the amount of
> time that you had used that specific compromised key, rather than
> every signature that you've ever made.
[snip]

Interesting thoughts. But another group of GnuPG gurus
(<http://keyring.debian.org/replacing_keys.html>) suggests simply
updating the original key. Are they right, wrong, or just different?

-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.