[dse 2018] ict討論區

2^10

其實D真係最有用

Key word: 10 bit user identity code
2¹⁰ = 1024

後面嗰個fake

如果大學讀CS 學D邏輯思維真係幫到好多
同埋得D唔係吹水野

core仲有冇郵件合併

應該有
Mc居多，lq 喺dse好似未出過，hkace mock 出過一次問procedure

有冇人可以答我normal form 係做乜？
成日分唔到 2NF 同3NF

同問

係咪elective 嘢嚟，冇讀過嘅

應該係elective A野？

郵件合併

屌奶星，差啲嚇死

連接lan到互聯網

Router : Divide a network to some small networks
Modem : Convert analog signal to digital signal

有冇人可以講下假設呀之類個d

Router:
1, Connect a network to the Internet
2, Connect two networks of different types (e.g. connect LAN and WAN)

Modem:
1, Convert digital signal to analogue signal
2, Convert analogue signal to digital signal

Modem比較舊，以前電話線上網就一定要用Modem（電話線係analogue signal）

What if analysis?

你電腦嘢係digital，但係cable 係只可以transfer analogue

utp cable=cat-5 通常係普通寬頻會用 100Mb/s 1000Mb/s個D
光纖速度會快過cat-5好多，原理係物理野呢科唔會考

2NF 係一個table有多過一個primary key 然後有d field淨係depends on其中一個
3NF 係有d field淨係depends on non-key attribute, 而唔係多過一個primary key然後淨係depends一個