Ip Header Number List - Watchguard Firebox X1000 Reference Manual

CHAPTER 1: Internet Protocol Reference
Attribute
Version
IHL
TOS
Tot_Len
ID
Flags
Frag_Off
TTL
Protocol
Check
Sour_Addr
Dest_Addr
Options

IP header number list

The IP Protocol header contains an 8-bit field that identifies the protocol
for the transport layer for the datagram.
2
Size
4 bits
4 bits
8 bits
16 bits
16 bits
3 bits
13 bits
8 bits
8 bits
16 bits
32 bits
32 bits
24 bits
Keyword Number
0
ICMP 1
IGMP 2
GGP 3
IP 4
ST 5
Description
IP format number (Current version = 4)
Header length in 32-bit words (Minimum = 5)
Type of service sets routing priorities. It is
generally under-utilized because few application
layers can set it.
Total length of packet measured in octets. It is
used in reassembling fragments.
Packet ID, used for reassembling fragments.
Miscellaneous flags
Identifies fragment part for this packet.
Time to live. It sets the maximum time the
datagram remains alive in the system.
IP protocol number. Indicates which of TCP ,
UDP , ICMP , IGMP , or other Transport protocol
is inside.
Checksum for the IP header
Source IP address
Destination IP address
IP Options (Present if IHL is 6)
Protocol
Reserved
Internet Control Message
Internet Group Management
Gateway-to-Gateway
IP-within-IP (encapsulation)
Stream
WatchGuard Firebox System