They are relevant if and only if you're looking for a corporate job related to networking. Your can begin your career from a networking assistant engineer with CCNA and work your way up to a network architect - probably requires CCIE and up. The exam is actually not very expensive, so you can might as well get yourself certified but I find it unnecessary to sign up for the course though. There are plenty of resources online, so just make full use of it and you'll be fine. (keyword: question dumps/braindumps) Some of the benefits from attending classes i can think of is that you get to strip your ethernet cable and plug them into the physical switches/routers and of course configure them. But in general, you're better off reading the books and playing with packet tracer/GNS3 at your own comfort.