- Jumbogram
In packet-switching computer networks, a jumbogram is a packet that is larger than the usual size limit for a given technology. The term jumbogram is a
portmanteau of "jumbo" and "datagram ".IPv6 jumbograms
A jumbogram is defined in RFC 2675 as "an IPv6 packet containing a payload longer than 65,535
octets ".The payload length field of
IPv4 andIPv6 has a size of 16 bits (capable of encoding 216 different unsigned integers, from 0 up to 216 − 1 = 65,535); hence, IP packets are limited to a maximum size of up to one byte less than 64KiB . An optional feature of IPv6, the "jumbo payload" option, allows the exchange of packets of up to one byte less than 4GiB (i.e., 232 − 1 = 4,294,967,295 bytes), by making use of a 32-bit length field. Packets with such long payloads are called "jumbograms".Since both TCP and UDP include fields limited to 16 bits (length, urgent data pointer), support for IPv6 jumbograms requires slight tweaks to the transport layer. Both the "jumbo payload" options and the transport-layer tweaks are described in RFC 2675.
See also
*
Jumbo frame – large packets for Ethernet
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