I interviewed with one of Raytheon's cybersecurity divisions as a recent college graduate.

1. On campus interview with university recruiter. Engineer himself; not an HR person. Behavioral interview. Was told I did very well and that I could get an endorsement through him for any position I applied for (see #2), which would greatly increase my chances of getting a response.
2. Apply to different jobs through company-wide online portal.
3. Phone interview with one of the developers.
4. Take-home programming test. Fairly difficult.
5. Group phone interview. This came on short notice after I sent a follow-up email a few weeks after I completed the programming test. They seemed a bit disorganized and hadn't realized I had actually submitted the completed programs.

Some may disagree with me, but I think this is somewhat forgivable since this group didn't seem to have any HR staff on hand; everybody I dealt with was regular development staff. Was told I'd be hearing more "very soon" and that the next stage in the process would probably involve another phone interview with some staff from the office I wanted to work in. I am clearly a security novice but they seemed interested in me regardless.

Haven't heard back from these guys yet, but it has only been a few weeks. I ended up accepting an offer from another company a few days after the Raytheon group call. Normally, I'd have followed up or sent a withdrawal notice by now, but I'm curious to see if I'm actually still considered a candidate, and if so, how long it actually takes to receive any sort of response. I'll inform them of my decision at that time if necessary.

An important point: Raytheon is something of an umbrella company. They've made a lot of acquisitions in recent years and several of their divisions retain a lot of operating autonomy. Consequently, the interview experience can vary wildly depending upon which group you're talking to.

Recruiter: Common behavioral questions. The recruiter asked to describe a technical challenge you've had to deal with and how you dealt with it, and to describe a conflict and how you resolved it, et al.

Phone interview: Basic questions about simple data structures and lower level elements of the C language (pointers, inline assembly, and so forth).

Group interview: More detailed questions about security concepts, especially relating to the Android and Linux platforms. Some were fairly challenging. I don't have much practical security experience and wasn't able to answer them all.