32.1.3 Internet Protocol Version 6 (IPv6)

<Structure of this section>

(1) IPv6 Packet Format

The formats and settings of IPv6 packets sent by the Switch conform to RFC8200. The following figure describes the format of an IPv6 packet.

Figure 32-20 IPv6 Packet Format

(2) IPv6 packet header validity checking

The 40-octet IPv6 header contains eight fields and two addresses. The following figure shows the format of an IPv6 header.

Figure 32-21 IPv6 header format

The Switch checks the validity of the IPv6 headers in IPv6 packets when IP packets are received. The following table describes the IPv6 packet header items that are checked.

Table 32-4 IPv6 packet header check contents
IPv6 packet header field	Check item	When a check error occurs Packet processing	Whether to send an ICMPv6 message for a discarded packet
Version	Be version = 6	Discarded	Do not send
Traffic class	Not checked.	-	-
Flow label	Not checked.	-	-
Payload length	Compare with the packet length. If the payload length is greater than the packet length, the packet is discarded.	Discarded	Do not send
Payload length	Compare with the packet length. The payload length must be less than the packet length.	Discarded	Do not send
Next header	Not checked.	-	-
Hop limit	The hop limit of the received packets directed to the local device is not checked.	-	-
Source address	The address is not a multicast address.	Discarded	Do not send
Destination address	The following conditions must be satisfied: The address is not the loopback address. Not a multicast address with a scope of 0 or 1	Discarded	Do not send

Legend:-: Not applicable

(3) IPv6 Extension Header Supported

The following table describes the IPv6 extension headers supported by the Switch.

TABLE 32-5 IPv6 extension header entries
IPv6 extension header	Type of IPv6 packet
IPv6 extension header	With the departing station of the equipment Packet to be	When the Switch arrives at the station Packet to be
Hop-by-Hop Options Header	OK	OK
Routing Header	NG	NG
Fragment Header	OK	OK
Authentication Header	NG	NG
Encapsulating Security Payload Header	NG	NG
Destination Options Header	NG	OK

(Legend) OK: Supported NG: Not supported-: No header processing