SCADA & EASY ~ looking for best solution

[Salty]

Greetings...

I have an exsisting setup of 6 Easy plc's networked. + 1 expansion on the 4th easy...

Easy 820 dc -rcx :net id 1 - Inlet & controll
Easy 820 dc -rcx :net id 2 - Filtering & Backwash control
Easy 820 dc -rcx :net id 3 - Cyclic and redundancy for the Waste Filters
Easy 820 dc -rcx :net id 4 - Waste discharge and clean up.
Easy 618 dc -re :net id 4.1
MFD-8B + CP8-NT + Display :net id 5 - General information and statistics
MFD-8B + CP8-NT + Display :net id 6 - Alarm's , fault's and trip's

It is for a waste water treatment plant, in a cement factory.
I have spanned the program over all 6 easy's, becuase we found that the easy would delay some functions ect when crammed into the first 3.

Now, after the job has been done and running for more than a year, the client expressed interest in intergrating the system with thier internal SCADA systems, via profibus DP, or even ethernet.

What i want to know is... "first time for me doing this" what would be the best practice, most cost effective procedure, without having to change the program *if possible.. how do i accomidate my clients needs?

He requires that all possible information, inputs, outputs, analog, totalizers, ect be availible to him via his internal structure...

Feel free to ask any questions should you require more info...

Note: they already have an exsisting SCADA provider, which is not OPC server.....

Thank you for any and all info in advance..

Kind Regards
Salty