https://github.com/jzplp/Computer-Network-A-Top-Down-Approach-Answer
第三章 3.5.6節 關於nmap的小實驗
實驗環境：windows10
實驗過程
-
windows沒有nmap工具，需要手動下載：https://nmap.org/
-
檢測目標主機某端口的TCP是否開放
- 無法到達指定的端口，可能是由於防火牆
nmap -sT -p80 192.168.2.220
Starting Nmap 7.80 ( https://nmap.org ) at 2019-12-07 14:48 ?D1ú±ê×?ê±??
Nmap scan report for MI9-jzphone.lan (192.168.2.220)
Host is up (0.074s latency).
PORT STATE SERVICE
80/tcp filtered http
MAC Address: A8:9C:ED:A7:D9:EC (Xiaomi Communications)
Nmap done: 1 IP address (1 host up) scanned in 2.33 seconds
- 端口打開
nmap -sT -p80 192.168.2.1
Starting Nmap 7.80 ( https://nmap.org ) at 2019-12-07 14:51 ?D1ú±ê×?ê±??
Nmap scan report for phicomm.me (192.168.2.1)
Host is up (0.0024s latency).
PORT STATE SERVICE
80/tcp open http
MAC Address: 68:DB:54:CC:6B:BE (Phicomm (Shanghai))
Nmap done: 1 IP address (1 host up) scanned in 1.47 seconds
- 端口關閉
nmap -sT -p80 192.168.2.239
Starting Nmap 7.80 ( https://nmap.org ) at 2019-12-07 14:56 ?D1ú±ê×?ê±??
Nmap scan report for LAPTOP-3CP7H0GM.lan (192.168.2.239)
Host is up (1.0s latency).
PORT STATE SERVICE
80/tcp closed http
Nmap done: 1 IP address (1 host up) scanned in 3.38 seconds
必須關閉防火牆，才能檢測到closed狀態。