Glycosidation and glycosylation
Glycosylation is a controlled process that involves a carbohydrate being attached to a hydroxyl or other functional group of another molecule. I think you meant to say glycation instead of glycosylation, and that is a random process that involves free sugars attaching to proteins. 

https://www.neb.com/faqs/2015/04/10/what-is-the-difference-between-glycosylation-and-glycation