Everything will be asked from basic to advanced including latest ongoing networking technologies, upcoming technologies, juniper products etc. Prepare thoroughly with all the small basics , Basics should be strong.
I applied through an employee referral. The process took 2 weeks. I interviewed at Juniper Networks (New York, NY) in Jan 2011
Interview
Interviews at Juniper is a pretty lengthy process. You will meet almost everyone you will be working with. They build a concensus based on your skills, personality attitude etc.
Interview questions [1]
Question 1
You will be asked to think out of the box. Resolve a problem multiple ways.