Juniper Networks Software Engineer interview questions

worst interview I ever have. phone interview was about some easy algorithms. then went to onsite interview. all of the interviewers asked me my favorite language and I said java. Seems they dont use java. Then I introduced my self that I have done a lot projects relate to backend side. All of them told me they are hiring front-end people. But I didn't know until the onsite interview. the first interviewer asked me a series of intellectual questions. the second people asked my resume projects. the third people asked my some system design(back-end stuff)(if you are hiring front-end, why system design is required?) plus coding questions. the last one is a manager. when he saw me, he just mean mug me. ask resume project. ask me whether I have taken OS class(if you are hiring front-end, why OS is required?). and also told me they were hiring front-end people. plus, asked me who gave me the phone interview. the whole interview made me confused and can not tell the feeling. after 3 weeks waiting, they give me a reject.

5 rounds of on-site interview. Ten minutes of interval between each ( you can choose to have more rest). The first round is more about projects on my resume, but these experienced engineers are able to find where is the key points in your description and dig deeper. Two rounds more about algorithm and data structure. One is about network design question