Linkedin Ettiquette part 2?

Is it ok to add people in Linkedin that work for the same company as you that you havent met? or should you only connect with people that you actually know?
Let me put it another way, I work for a medium to large retailer and can see many people who do also. I can see the benefit of networking within the company so would like to connect with them, but im not even going to request it if its not the done thing!