Some registers that may help work out the error in riscv: scause (Supervisor Cause Register) indicates the type of the page fault. sepc: Supervisor Exception Program Counter stval (Superviso...

Isolation Real world examples Think in Strawman design: If no operating system, there is no strong isolation between programs. Unix interface abstracts the hardware resources. processes: ...

This lab requires python<=3.12 (to import module pipes). I’d like to record my process of implementing primes.c. At first, I didn’t know that subprocess who forked from the parent should clos...

OS purposes Abstract the hardware Both for convenient and portability Multiplex Of applications Isolation Between applications Sha...

What is multicast Imagine this scenario: An example of network topology for multicast Now A wants to send same packets to address group containing B, C, E, and X. It can simply send packets ove...

Routers RIP enable conf t[erminal] router rip [version 2] net[work] <ip-address-1> # Declare connected network net[work] <ip-address-2> net[work] ...

What happened My systemd service clash won’t start on boot, which is under user mode. What I’ve done: In [Unit], Change After=network.target to After=default.target. This is because that...

End-to-end routing Approaches Flooding. As its name, packets go anywhere (it may form loops). Sourcing routing. Source router put the full path (from source to destination) in packets. For...

Introduction Network address translation (NAT) is a gate between local network and the Internet. It translates/rewrites internal IP address to external IP address When packet is sent from interna...

User Datagram Protocol (UDP) Checksum includes pseudo header Transport Control Protocol (TCP) Automatic Repeat reQuest (ARQ) There are three ARQ protocols as follows: Stop and Wait prot...