Input/Output Subsystem and Device Interaction

Input/Output Subsystem and Device Interaction

This lecture introduces the IO subsystem, covering device models, device controllers, device drivers, IO communication methods like programmed IO, interrupts, and direct memory access (DMA). It also explains the OS’s role in managing device IO via layered abstractions.

Demand Paging and Page Fault Handling

Demand Paging and Page Fault Handling

This lecture details demand paging in virtual memory systems, explaining page tables, page faults, swap space, page replacement policies like FIFO and LRU, and how OS handles page faults and optimizes memory usage

Speak-up Bandwidth-Based DDoS Defense Mechanism

Speak-up Bandwidth-Based DDoS Defense Mechanism

This paper proposes Speak-up, a bandwidth-based defense mechanism against application-level DDoS attacks. It encourages all clients to send traffic proportional to their upload bandwidth, allowing legitimate clients to outcompete attackers fairly. The system includes a virtual auction and payment channels to enforce proportional resource sharing.

Memory Management Concepts

Memory Management Concepts

This lecture covers memory management, including virtual memory, paging, segmentation, page tables, translation lookaside buffers (TLBs), and address translation mechanisms. It explains how OS and hardware collaborate to provide isolation and efficient memory use.

IO Virtualization Techniques

IO Virtualization Techniques

This document explains IO virtualization concepts including device passthrough, paravirtualization, and virtual device drivers. It discusses challenges in virtualizing hardware devices for multiple virtual machines and solutions to maintain performance and security in IO operations.