[Chroma]

Another user posted regarding different individuals using the same connection and login account and the possibility of visiting a friend and being essentialy kept in the dark with regards to how his data was being handled and it got me thinking.

Is there intercompatibility between ISP's?

Lets say for a minuite that i opt in (purely for the sake of the argument) and i do this using my laptop's wifi whilst sitting at a cafe connected through BT.

Suddenly i hear that theyre out of blueberry muffins but that the cafe down the road has some, so i pack my gear and leg it down the street to secure some blueberry filled goodness.
I unpack my laptop and hook into the wifi which this time is provided by Carphone Warehouse (whos flown surprisingly low under the radar up till now)

Several questions arise at this point.
Will i still be opted in?
Will i be presented another opt in/out/shake-it-all-about screen?
Will my laptop melt under the strain of desperately trying to divide by zero?
Will the cookie provided by BT's cookiemongler (for want of a better term) be valid on carphone warehouses equipment?

on the last point regarding cookies i cant see this as being possable in a purely technical sense, i mean without going too far into moonspeak math/code jargon; numbers generated by a computer are not even close to random.

Take a playlist for instance, if you select randomise then it will go through every track in a seemingly random pattern till it plays all the tracks then it will stop.
In a truly random system however its more than likely that certain songs will be played more than once some may even be played several times.

The same kind of principle applies to the term UNIQUE ID, in that much like a playlist no string will be produced twice on the same system in order to maintain that each string is indeed UNIQUE.
However two systems are in play here and therefore the chances of me winding up with the same UID as Jonh Doe although extremely slim appear to be very real.
I mean the BT/PHORM equipment generates a random UID that it assigns to me.
The Carphone/PHORM equipment would do the same, and unless there was direct communication between the two ISP's equipment then neither cookiemongler would know which UID's where already in the system.

Doesnt this pose a significant problem for the actual database?
I mean a database frankly goes into meltdown when two unique keys are the same for two different tables (unless theres a secondary key to differentiate)

So am i completely missing something here or are the cookies assigned further down the equipment line where presumably multiple ISP's funnel the data through?

If so then this raises a further interesting question:
how can BT even begin to concieve of a setup thats a cookie free opt in/out/shake-it-all-about setup without having consultations with other ISP's that would most definately be effected by such modifications?