[STUDY VLOG] study landscape # 15

• Computer network: the data link layer
  • Definitions and the data link layer
    • Link: a link via only a portion of
    • Data link: data link transmission = link control protocol data + (different)
    • Channels used: point channel and a broadcast channel
    • Frame: service data unit is vertical, horizontal agreements
    • basic skills:
      • Encapsulated in a frame: special control characters
      • Transparent transmission: character fill
      • Error detection: bit errors, missing frames, repeating frames, frames out of sequence
        • CRC cyclic redundancy check generator polynomial selected critical, error-free acceptance can do
  • Point to Point Protocol PPP
    • Transparent package, simple error detection; parameter negotiation; support upward, downward compatibility; Dynamic Allocation
    • Composition: encapsulating IP datagrams to the serial link; the LCP Link Control Protocol; NCP Network Control Protocol
    • Five stages: establishing a link LCP; validation; network control negotiation; conversation maintenance phase; terminate PPP
• database:
  • Nested query
  • Pintia practice
• Total net experiment: Experiment 7

2020.3.31

• Intends to April start brushing LeetCode
• Stabilize the biological clock to get up before seven, eleven before sleep
• Start planning carefully, do not feel too deliberately
• In order to record something more than ready to start adding some on a daily Momentum hhhha
• “Sometimes the questions are complicated and the answers are simple.”