Datasheet

____________________________________________________ DS34S101, DS34S102, DS34S104, DS34S108
Rev: 032609 42 of 198
10.6.1.6 L2TPv3/IPv4 Header
Figure 10-17. L2TPv3/IPv4 Header Format
0
0 1 2 3 4 5 6 7 8 9 0
1
0
2
0
3
1
IPVER
IHL
IP TOS
TOTAL LENGTH
IDENTIFICATION
FLAGS
FRAGMENT OFFSET
TIME TO LIVE
PROTOCOL
IP HEADER CHECKSUM
SOURCE IP ADDRESS
DESTINATION IP ADDRESS
SESSION ID = PW LABEL
IP
HEADER
1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9
COOKIE 1 (OPTIONAL)
COOKIE 2 (OPTIONAL)
L2TPv3
HEADER
Table 10-12. IPv4 Header Fields (L2TPv3)
Field
Description
IPVER
See Table 10-7.
IHL
IP TOS
Total Length
Identification
Flags
Fragment Offset
Time To Live
Protocol
Must be set to 0x73 to signify L2TPv3
IP Header Checksum
See Table 10-7.
Source IP Address
Destination IP Address
Table 10-13. L2TPv3 Header Fields
Field
Description
Session ID (32 bits)
Locally significant L2TP session identifier, Contains the bundle identifier. All bundle identifiers are
available for use except 0, which is reserved.
Cookie (32 or 64 bits)
Optional field that contains a randomly selected value used to validate association of the packet
with the expected bundle identifier