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/etc/protocols is in netbase 5.0.

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The actual contents of the file can be viewed below.

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# Internet (IP) protocols
#
# Updated from http://www.iana.org/assignments/protocol-numbers and other
# sources.
# New protocols will be added on request if they have been officially
# assigned by IANA and are not historical.
# If you need a huge list of used numbers please install the nmap package.

ip	0	IP		# internet protocol, pseudo protocol number
#hopopt	0	HOPOPT		# IPv6 Hop-by-Hop Option [RFC1883]
icmp	1	ICMP		# internet control message protocol
igmp	2	IGMP		# Internet Group Management
ggp	3	GGP		# gateway-gateway protocol
ipencap	4	IP-ENCAP	# IP encapsulated in IP (officially ``IP'')
st	5	ST		# ST datagram mode
tcp	6	TCP		# transmission control protocol
egp	8	EGP		# exterior gateway protocol
igp	9	IGP		# any private interior gateway (Cisco)
pup	12	PUP		# PARC universal packet protocol
udp	17	UDP		# user datagram protocol
hmp	20	HMP		# host monitoring protocol
xns-idp	22	XNS-IDP		# Xerox NS IDP
rdp	27	RDP		# "reliable datagram" protocol
iso-tp4	29	ISO-TP4		# ISO Transport Protocol class 4 [RFC905]
dccp	33	DCCP		# Datagram Congestion Control Prot. [RFC4340]
xtp	36	XTP		# Xpress Transfer Protocol
ddp	37	DDP		# Datagram Delivery Protocol
idpr-cmtp 38	IDPR-CMTP	# IDPR Control Message Transport
ipv6	41	IPv6		# Internet Protocol, version 6
ipv6-route 43	IPv6-Route	# Routing Header for IPv6
ipv6-frag 44	IPv6-Frag	# Fragment Header for IPv6
idrp	45	IDRP		# Inter-Domain Routing Protocol
rsvp	46	RSVP		# Reservation Protocol
gre	47	GRE		# General Routing Encapsulation
esp	50	IPSEC-ESP	# Encap Security Payload [RFC2406]
ah	51	IPSEC-AH	# Authentication Header [RFC2402]
skip	57	SKIP		# SKIP
ipv6-icmp 58	IPv6-ICMP	# ICMP for IPv6
ipv6-nonxt 59	IPv6-NoNxt	# No Next Header for IPv6
ipv6-opts 60	IPv6-Opts	# Destination Options for IPv6
rspf	73	RSPF CPHB	# Radio Shortest Path First (officially CPHB)
vmtp	81	VMTP		# Versatile Message Transport
eigrp	88	EIGRP		# Enhanced Interior Routing Protocol (Cisco)
ospf	89	OSPFIGP		# Open Shortest Path First IGP
ax.25	93	AX.25		# AX.25 frames
ipip	94	IPIP		# IP-within-IP Encapsulation Protocol
etherip	97	ETHERIP		# Ethernet-within-IP Encapsulation [RFC3378]
encap	98	ENCAP		# Yet Another IP encapsulation [RFC1241]
#	99			# any private encryption scheme
pim	103	PIM		# Protocol Independent Multicast
ipcomp	108	IPCOMP		# IP Payload Compression Protocol
vrrp	112	VRRP		# Virtual Router Redundancy Protocol [RFC5798]
l2tp	115	L2TP		# Layer Two Tunneling Protocol [RFC2661]
isis	124	ISIS		# IS-IS over IPv4
sctp	132	SCTP		# Stream Control Transmission Protocol
fc	133	FC		# Fibre Channel
mobility-header 135 Mobility-Header # Mobility Support for IPv6 [RFC3775]
udplite	136	UDPLite		# UDP-Lite [RFC3828]
mpls-in-ip 137	MPLS-in-IP	# MPLS-in-IP [RFC4023]
manet	138			# MANET Protocols [RFC5498]
hip	139	HIP		# Host Identity Protocol
shim6	140	Shim6		# Shim6 Protocol [RFC5533]
wesp	141	WESP		# Wrapped Encapsulating Security Payload
rohc	142	ROHC		# Robust Header Compression