82598EB Datasheet, PDF (263/596 Pages) Intel Corporation – Intel® 82598EB 10 Gigabit Ethernet Controller Datasheet

Intel^® 82598EB 10 GbE Controller - Transmit Functionality
The Layer 4 Protocol ID value in the pseudo-header identifies the upper-layer protocol (such as, 6 for
TCP or 17 for UDP).
IPv6 Source Address
IPv6 Final Destination Address
TCP/UDP Packet Length
Zero
Next Header
Figure 3-34. TCP/UDP Pseudo Header Content for IPv6 (Traditional Representation)
Note: From the RFC2460 specification:
• If the IPv6 packet contains a routing header, the destination address used in the pseudo-header
is that of the final destination. At the originating node, that address is in the last element of the
routing header; at the recipient(s), that address is in the Destination Address field of the IPv6
header.
• The next header value in the pseudo-header identifies the upper-layer protocol (such as, 6 for
TCP or 17 for UDP). It differs from the next header value in the IPv6 header if there are extension
headers between the IPv6 header and the upper-layer header.
• The upper-layer packet length in the pseudo-header is the length of the upper-layer header and
data (TCP header plus TCP data). Some upper-layer protocols carry their own length information
(such as Length field in the UDP header); for such protocols, that is the length used in the
pseudo- header. Other protocols (such as TCP) do not carry their own length information, in which
case the length used in the pseudo-header is the payload length from the IPv6 header, minus the
length of any extension headers present between the IPv6 header and the upper-layer header.
• Unlike IPv4, when UDP packets are originated by an IPv6 node, the UDP checksum is not
optional. That is, whenever originating a UDP packet, an IPv6 node must compute a UDP
checksum over the packet and the pseudo-header, and, if that computation yields a result of zero,
it must be changed to hex FFFF for placement in the UDP header. IPv6 receivers must discard
UDP packets containing a zero checksum, and should log the error.
A type 0 routing header has the following format:
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