Basic CSE related questions on CN,OS

Prepare compact explanations anchored in a concrete flow. For operating systems, distinguish process from thread, user mode from kernel mode, virtual memory from physical RAM, and deadlock conditions from starvation. Explain a context switch as saving and restoring execution state, then note why excessive switching costs CPU cache locality. For networking, trace a browser request through DNS resolution, TCP connection setup, TLS, HTTP request and response, then discuss retries and idempotency. Be ready to compare TCP reliability and ordering with UDP latency and application-level responsibility. Do not claim a process shares all memory with another process, or that HTTPS means an application is automatically safe. Discuss measurements such as latency percentiles, packet loss, run queue, page faults, and CPU utilization. Complexity is not the main metric here, but use correct order language where applicable: a page-table lookup is typically designed to be effectively constant-time through hardware translation caching, while scanning a connection table is O(n) unless indexed.