NCK, NSCK, CCK, and SPCK, what mean?

[Mirken]

NCK is the achronym of Network Code Key for the operator lock
NSCK is the achronym of Network Subside Code Key but for what is it?
CCK and SPCK what mean and for what they are?

thanx in advance


sorry for my english, maybe i made some errors.

[ahib]

NCK-Net Code Key
NSCK= Net Subset Code Key
CCK= Corporate Code Key and
SPCK=Service Provider Code Key

I THINK I think, therefore I am! NO! that is wrong!- I AM, therefore I (should) THINK!

[Mirken]

thank you Ahib

do you know the usefulness of each one of the code?

many thanks