寫作之難，在於把網狀的思考，用樹狀結構，展現在線性展開的語句裡。

  TLD (Top-Level Domain) A TLD is the most righthand part of a domain name. So, for example, the tryhackme.com TLD is  .com . There are two types of TLD, gTLD (Generic Top Level) and ccTLD (Country Code Top Level Domain).  Second-Level Domain Taking tryhackme.com as an example, the .com part is the TLD, and tryhackme is the Second Level Domain. When registering a domain name, the second-level domain is limited to 63 characters + the TLD and can only use a-z 0-9 and hyphens (cannot start or end with hyphens or have consecutive hyphens). Subdomain A subdomain sits on the left-hand side of the Second-Level Domain using a period to separate it; for example, in the name admin.tryhackme.com the admin part is the subdomain. A subdomain name has the same creation restrictions as a Second-Level Domain, being  limited to 63 characters and can only use a-z 0-9 and hyphens (cannot start or end with hyphens or have consecutive hyphens).  You can use multiple subdomains split...

這篇文章沒有太多的實作細節，但是內容我有親自實作過是可行的。 因為工作上常會需要監聽Wi-Fi封包，看看RD的實作有沒有問題，所以一直有在研究監聽Wi-Fi封包的軟體或是工具。 如果要抓封包來看，第一首選MacBook Pro，一買來就可以用，不用安裝其他軟體，而且它是一個貨真價實的電腦，使用上相當方便。 但是MacBook 系列到今天(2020/10/18)為止，都還沒支援Wi-Fi 6，如果需要監聽Wi-Fi 6的封包，我也找了一個方法：Nvidia Jetson Nano + Intel AX 200。 詳情請看參考網址內，外國的朋友是怎麼做的。 參考網址： https://www.semfionetworks.com/blog/80211ax-remote-packet-captures-using-the-jetson-nano

  Use: save a s script file such as ip.sh and ./ip.sh xxx OOO, it means ping every XXX*n+OOOth packet. #!/bin/bash count=1 cat Type1_black.list | while read line do if [  expr $count % $1  -eq $2 ] then echo ‘==============================’ echo  expr $count echo  date echo $line #ping -c 10 -W 1 $line ping -c 10 $line #echo ‘==============================’ fi count=$[$count+1] done

  aria2c.exe –conf-path=aria2.conf http://blackarch.cs.nctu.edu.tw/iso/blackarch-linux-full-2021.09.01-x86_64.iso https://ftp.halifax.rwth-aachen.de/blackarch/iso/blackarch-linux-full-2021.09.01-x86_64.iso https://www.mirrorservice.org/sites/blackarch.org/blackarch/iso/blackarch-linux-full-2021.09.01-x86_64.iso https://mirrors.dotsrc.org/blackarch/iso/blackarch-linux-full-2021.09.01-x86_64.iso aria2c.exe –conf-path=aria2.conf http://linux.cis.nctu.edu.tw/blackarch/ova/blackarch-linux-2021.09.01.ova https://mirrors.cloud.tencent.com/blackarch/ova/blackarch-linux-2021.09.01.ova https://mirrors.dotsrc.org/blackarch/ova/blackarch-linux-2021.09.01.ova http://ubuntu.mirrorservice.org/sites/blackarch.org/blackarch/ova/blackarch-linux-2021.09.01.ova https://mirror.digitalpacific.com.au/blackarch/ova/blackarch-linux-2021.09.01.ova https://mirror.yandex.ru/mirrors/blackarch/ova/blackarch-linux-2021.09.01.ova https://ftp.icm.edu.pl/pub/Linux/distributions/blackarch/ova/blackarch-linux-2021.09...

 #For Installing Mongo DB echo "deb http://security.ubuntu.com/ubuntu focal-security main" | sudo tee /etc/apt/sources.list.d/focal-security.list sudo apt-get update sudo apt-get install libssl1.1 apt install vim apt install net-tools apt install openssh-server apt install iftop apt install sysstat apt install htop apt install putty apt install minicom apt install tmux apt install inetutils-traceroute apt install traceroute apt install ethtool

  https://www.3gpp.org/dynareport?code=38-series.htm 38.211 NR; Physical channels and modulation 1. 計算Tc跟Ts， Tc=0.509ns 2. 5G NR Frame Structure 3. Bandwidth Part 1. https://www.sharetechnote.com/html/5G/5G_Phy_TimingUnit.html 2. https://www.sharetechnote.com/html/5G/5G_FrameStructure.html 3. https://www.sharetechnote.com/html/5G/5G_CarrrierBandwidthPart.html 38.411

 用這個網頁進行計算。 https://5g-tools.com/5g-nr-throughput-calculator/ Mode of Modulation and Code Rate: Auto (3GPP 38.214) UL選 38.214-Table 5.1.3.1-1 DL選 38.214-Table 5.1.3.1-2 BW(j) = BW:100MHz FR1 µ:30kHz Overhead OH(j) for control channels Mode: Auto 3GPP 38.306 Mode of Symbols allocation: Vendor data Simple, 7:3 分別計算f(j)=1 & f(j)=0.75。