It’s highly illogical to compare a well-recognized brand like ISB with a no-name institute like IBS. It seems you are a bit confused between the 2 schools because comparing them is a literal joke. 

ISB is ranked 1st in India and 4th in Asia and 32nd in the World at Best B Schools. It’s a B School that competes with top B schools like IIM ABC and here you are comparing it with a C grade B school in the country. 

Almost anyone can get into IBS owing to the low qualifying scores needed and high number of seats available. Whereas getting into ISB is difficult even with a GMAT score as high as 99 percentile. ISB has the best corporate relations team in India and they work hard to get the roles that you want in the corporate sector.

The two colleges may share the same alphabet in their acronyms but there are nowhere similar when it comes to the brand name and worth.