RATE ROUTING - URGENT

Hi all,

I know the functions of rate routing. it is used in REM. Why this only used in REM? What is the speciality? In Rate routing wat is the meaning of RATE?

What is the main difference b/w std & Rate?

I already studied all threads abt the rate routing. so don't repeat the same basic answers.

Expecting ur valuable replies............

Regards,

S.ganesh