To The Best of Your Knowledge

[Grlygrl201@aol.com]

As you know, I've had some difficulty grasping the concept of P2P.  I think I 
get it now.  Is the following correct?

Suppose I have to pick one gem as my favorite, let's say "sapphires"  Every 
time
someone comes up and asks me what my favoite gem is, I say "sapphire."  You 
also becomes the keeper of my favoite gem information.  Anytime
anyone asks "I want to buy Geege jewelry for her birthday, what's her 
favorite?" you are required to answer correctly.  This can happen in two ways:

1) "It was sapphires last time I checked."  (asynchronous)
2) "Wait there while I go {email, call, talk to} her." "Geege, what's
   your favorite gem?  Sapphires?  Okay, thanks."  Answer: My favorite gem
   is the (blue-black) sapphire.  (syncrhonous)

Which one's going to take longer? Obviously the second one.  

Meanwhile, as I stroll past Tiffanys a pair of emerald and diamond drop 
earings catch my eye. I decide that I now favor emeralds.  I can:

1) Keep this information to myself and the worst that can happen is that 
anyone who doesn't ask will risk getting me a sapphire instead of an emerald 
for my birthday. (inconsistent data space - easy to do but may cost/cause 
some difficulty down the road by way of returned jewels).  (Magi/Web)

2) You could call everyone I know and tell them that my favorite gem is now 
emerald -but it may be difficult for you to find all the people I know. 
There's no way to guarantee that every single person can be updated, much 
less figure out who needs to know. (forced consistency - very complex and 
costly up front, but very little downstream costs).(Groove)
3) "Alert the media," i.e. swarmcast my new preference and hope that the 
update will reach everyone eventually.  My mother read in US Snooze & World 
Report that I am bullish on emeralds, but my best friend Marianne doesn't 
read such rags and  believes I'm still into sapphires. (best expedient 
consistency using resources available) (OpenCOLA) 

Ten minutes later someone else comes up to you and asks, "What's Geege's fav 
jewel?"  

For 1) You decide if it's convenient and cheap enough to contact me; you will 
call and discover I've changed my tastes.  If it's neither, you'll answer 
"Sapphires, last time I checked."  
2) Your answer is "I don't know," until you confirm with me, at which time 
it'll be emeralds.
3) You think the answer is sapphires, but you ask my mom when the last time 
she's        heard anything about my gem preference, in which case she will 
tell you it's emeralds.. (She gets USN&WR pushcast to her WAP phone).  You 
decide her
information is most current and answer "emeralds."