以下是使用 nmap 工具扫描指定主机支持哪些 IP 协议（TCP、ICMP、IGMP等）的三个实例。nmap 工具可以上 http://insecure.org/nmap 网站下载。
一、
D:\Program Files\nmap-5.21>nmap -sO 192.168.1.12 | more
Starting Nmap 5.21 ( http://nmap.org ) at 2010-01-30 21:36 中国标准时间
Skipping IPProto Scan against 192.168.1.12 because Windows does not support scan
ning your own machine (localhost) this way.
Nmap scan report for 192.168.1.12
Host is up.
PROTOCOL STATE SERVICE
0 unknown hopopt
1 unknown icmp
2 unknown igmp
3 unknown ggp
4 unknown ip
5 unknown st
6 unknown tcp
7 unknown cbt
8 unknown egp
9 unknown igp
10 unknown bbn-rcc-mon
11 unknown nvp-ii
12 unknown pup
13 unknown argus
14 unknown emcon
15 unknown xnet
16 unknown chaos
17 unknown udp
18 unknown mux
19 unknown dcn-meas
20 unknown hmp
21 unknown prm
22 unknown xns-idp
23 unknown trunk-1
24 unknown trunk-2
25 unknown leaf-1
26 unknown leaf-2
27 unknown rdp
28 unknown irtp
29 unknown iso-tp4
30 unknown netblt
31 unknown mfe-nsp
32 unknown merit-inp
33 unknown dccp
34 unknown 3pc
35 unknown idpr
36 unknown xtp
37 unknown ddp
38 unknown idpr-cmtp
39 unknown tp++
40 unknown il
41 unknown ipv6
42 unknown sdrp
43 unknown ipv6-route
44 unknown ipv6-frag
45 unknown idrp
46 unknown rsvp
47 unknown gre
48 unknown mhrp
49 unknown bna
50 unknown esp
51 unknown ah
52 unknown i-nlsp
53 unknown swipe
54 unknown narp
55 unknown mobile
56 unknown tlsp
57 unknown skip
58 unknown ipv6-icmp
59 unknown ipv6-nonxt
60 unknown ipv6-opts
61 unknown anyhost
62 unknown cftp
63 unknown anylocalnet
64 unknown sat-expak
65 unknown kryptolan
66 unknown rvd
67 unknown ippc
68 unknown anydistribfs
69 unknown sat-mon
70 unknown visa
71 unknown ipcv
72 unknown cpnx
73 unknown cphb
74 unknown wsn
75 unknown pvp
76 unknown br-sat-mon
77 unknown sun-nd
78 unknown wb-mon
79 unknown wb-expak
80 unknown iso-ip
81 unknown vmtp
82 unknown secure-vmtp
83 unknown vines
84 unknown ttp
85 unknown nsfnet-igp
86 unknown dgp
87 unknown tcf
88 unknown eigrp
89 unknown ospfigp
90 unknown sprite-rpc
91 unknown larp
92 unknown mtp
93 unknown ax.25
94 unknown ipip
95 unknown micp
96 unknown scc-sp
97 unknown etherip
98 unknown encap
99 unknown anyencrypt
100 unknown gmtp
101 unknown ifmp
102 unknown pnni
103 unknown pim
104 unknown aris
105 unknown scps
106 unknown qnx
107 unknown a/n
108 unknown ipcomp
109 unknown snp
110 unknown compaq-peer
111 unknown ipx-in-ip
112 unknown vrrp
113 unknown pgm
114 unknown any0hop
115 unknown l2tp
116 unknown ddx
117 unknown iatp
118 unknown stp
119 unknown srp
120 unknown uti
121 unknown smp
122 unknown sm
123 unknown ptp
124 unknown isis-ipv4
125 unknown fire
126 unknown crtp
127 unknown crudp
128 unknown unknown
129 unknown unknown
130 unknown unknown
131 unknown unknown
132 unknown unknown
133 unknown unknown
134 unknown unknown
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255 unknown unknown
Nmap done: 1 IP address (1 host up) scanned in 0.39 seconds
二、
D:\Program Files\nmap-5.21>nmap -sO 192.168.1.20 | more
Starting Nmap 5.21 ( http://nmap.org ) at 2010-01-30 21:44 中国标准时间
Nmap scan report for 192.168.1.20
Host is up (0.00s latency).
All 256 scanned ports on 192.168.1.20 are open|filtered
MAC Address: 00:1D:72:2E:F7:64 (Wistron)
Nmap done: 1 IP address (1 host up) scanned in 7.38 seconds
三、
D:\Program Files\nmap-5.21>nmap -sO 192.168.1.1 | more
Starting Nmap 5.21 ( http://nmap.org ) at 2010-01-30 21:45 中国标准时间
Nmap scan report for 192.168.1.1
Host is up (0.00s latency).
Not shown: 255 open|filtered protocols
PROTOCOL STATE SERVICE
1 open icmp
MAC Address: 00:21:27:29:D0:F0 (Tp-link Technology Co.)
Nmap done: 1 IP address (1 host up) scanned in 6.42 seconds
第一与第二都是电脑，而第三个则是路由器。可见此路由器只支持一个ICMP协议。