# Frontmatter
Lecture: 12-2PM Mon
Lab: Attendance Taken
Textbook: Hogan 'Small, Sharp Software Tools'
## Topics
W1: representations (binary, numbers, characters, instructions), operating system introduction
W2: processes
W3: file system, name space
W4: the boot sequence
W5: virtual machines
W6: networks
W7: internet protocol
W8: domain name service, application layer
W9: computer and network security
<Mid-semester break>
W10: cloud computing (self-study: public holiday)
W11: Social Network Analysis
W12: Micro-services and APIs
W13: course review
## Assessment
Title | % | Due | Total
HW 1 | 5% | W3 | 5/5%
A1 nix | 20% | W5 | 23.5/25%
HW 2 | 5% | W4 | 28.5/30%
HW 3 | 5% | W7 | 33.5/35%
HW 4 | 5% | W9 | 38.5/40%
A2 nw | 20% | W11 | /60%
Final | 40% | ExamP | /100%
## Week 1
## Week 4
Memory mapping:
- OS reroutes memory request (ie. read_mem(ptr = 0) -> read_phys_mem(ptr + offset = 1000))
- Pages more sophisticated; allows mapping to other media (ie. swap/disk)
Scheduling: Round robin, fair share (NE)
- Priority 0(max)-39(min); normal user proc. 20 default
- `(re)nice -n 10 $mycommand` => nice[mycommand] += 10
Bootstrap
1. RAM, ROM, flash: Tests
2. BIOS/MBR: phys_mem(inital_address := 0) = JMP INSTRUCTION
4. GRUB
5. Kernel
6. init
7. system processes launched
## Week 5
Emulator: simulate/translate CPU instructions, not usually all aspects (I/O, memory mgmt.)
Virtual Machine: simualte all aspects of target system
Container: Intercept syscalls to provide standardized environment with less overhead than VM
## Week 6
Circuit switching: each data connection is allocated a circuit via exchanges
Packet switching: each data connection is divided into packets, which are sent independantly
- Packets can take different routes; avoid congestion, fault tolerance
- Packets can arrive out of order (cf. TCP)
LAN and WAN: WAN is interconnected network of LANs.
Ethernet: most common LAN technology, applies to wired and wireless. `Ethernet Packet(Data Packet)`
-> Example of layering, actually more like `Ethernet(Internet(Transport(Data)))`: https://stackoverflow.com/questions/31446777/difference-between-packets-and-frames
-> At the Internet layer we include an IP address; 32bit/4bytes (dotted quads)
-> TCP layer includes instructions to reconstruct out-of-order packets
## Week 9: Computer and Network Security [L03,L04,L06,L09]
Cloud provider provisions VM based on requested resources
Better security (DoS prevention, etc.)
More options (ie. locations, etc.)
Cheaper and scale more easily, since clients "share" physical resources with many companies.