0 ip
1 icmp
2 igmp
3 ggp
4 ipencap
5 st2
6 tcp
7 cbt
8 egp
9 igp
10 bbn-rcc
11 nvp
12 pup
13 argus
14 emcon
15 xnet
16 chaos
17 udp
18 mux
19 dcn
20 hmp
21 prm
22 xns-idp
23 trunk-1
24 trunk-2
25 leaf-1
26 leaf-2
27 rdp
28 irtp
29 iso-tp4
30 netblt
31 mfe-nsp
32 merit-inp
33 sep
34 3pc
35 idpr
36 xtp
37 ddp
38 idpr-cmtp
39 tp++
40 il
41 ipv6
42 sdrp
43 ipv6-route
44 ipv6-frag
45 idrp
46 rsvp
47 gre
48 mhrp
49 bna
50 esp
51 ah
52 i-nlsp
53 swipe
54 narp
55 mobile
56 tlsp
57 skip
58 ipv6-icmp
59 ipv6-nonxt
60 ipv6-opts
62 cftp
64 sat-expak
65 kryptolan
66 rvd
67 ippc
69 sat-mon
70 visa
71 ipcv
72 cpnx
73 cphb
74 wsn
75 pvp
76 br-sat-mon
77 sun-nd
78 wb-mon
79 wb-expak
80 iso-ip
81 vmtp
82 secure-vmtp
83 vines
84 ttp
85 nsfnet-igp
86 dgp
87 tcf
88 eigrp
89 ospf
90 sprite-rpc
91 larp
92 mtp
93 ax.25
94 ipip
95 micp
96 scc-sp
97 etherip
98 encap
100 gmtp
101 ifmp
102 pnni
103 pim
104 aris
105 scps
106 qnx
107 a/n
108 ipcomp
109 snp
110 compaq-peer
111 ipx-in-ip
112 vrrp
113 pgm
115 l2tp
116 ddx
117 iatp
118 st
119 srp
120 uti
121 smp
254 divert