Cisco Software Engineer interview questions

Basic C questions (Pointer,Structures,linked list, arrays,data types), Computer Networking concepts (TCP/IP,UDP). I was interviewed for 1 hour. It was pretty simple. Though I screwed up in some of them. I could not answer most efficient way in finding number of 1's in a given number.

Applied online and got a phone interview with Cisco Systems for a software engineering position. The interviewer was very friendly and first started asking questions on my resume and previous projects. Then slowly started asking more difficult questions geared towards programming and networking knowledge. The interview lasted for almost one hour with most questions of the type "what are threads?, what are local and global variables?, what is heap memory?, explain tcp sliding window mechanism and congestion avoidance", etc. Overall it was a fairly good interview experience and I'm waiting to hear back from them about the results.