GST rate... how to read it?

Rupa Sharma (In job) (35 Points)

22 May 2017  
When we say GST on furniture is at the rate of 28% vs existing rate of 26%. So what is 28%? Is it CGST or both CGST plus SGST? If it is CGST, then does it mean the real rate impact is of 28*2=56%?