Dell PowerSwitch S4820T Configuration Guide for the S4820T System 9.100.0 - Page 419

Payload Length (16 bits) The Payload Length field specifies the packet payload. This is the length of the data following the IPv6 header. IPv6 Payload Length only includes the data following the header, not the header itself. The Payload Length limit of 2 bytes requires that the maximum packet payload be 64 KB. However, the Jumbogram option type Extension header supports larger packet sizes when required. Next Header (8 bits) The Next Header field identifies the next header's type. If an Extension header is used, this field contains the type of Extension header (as shown in the following table). If the next header is a transmission control protocol (TCP) or user datagram protocol (UDP) header, the value in this field is the same as for IPv4. The Extension header is located between the IP header and the TCP or UDP header. The following lists the Next Header field values. Value Description 0 Hop-by-Hop option header 4 IPv4 6 TCP 8 Exterior Gateway Protocol (EGP) 41 IPv6 43 Routing header 44 Fragmentation header 50 Encrypted Security 51 Authentication header 59 No Next Header 60 Destinations option header NOTE: This table is not a comprehensive list of Next Header field values. For a complete and current listing, refer to the Internet Assigned Numbers Authority (IANA) web page at . Hop Limit (8 bits) The Hop Limit field shows the number of hops remaining for packet processing. In IPv4, this is known as the Time to Live (TTL) field and uses seconds rather than hops. Each time the packet moves through a forwarding router, this field decrements by 1. If a router receives a packet with a Hop Limit of 1, it decrements it to 0 (zero). The router discards the packet and sends an ICMPv6 message back to the sending router indicating that the Hop Limit was exceeded in transit. IPv6 Routing 419