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cisco - are jumbo frames supported in ipv6

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Are jumbo frames supported in ipv6 on cisco devices? Or in general?
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Top Expert 2011
Yes, IPv6 is supported as well as Jumbo frames?


I have done additional research.

My question regards IPv6's lack of support for packet fragmentation.

i.e. If you have an ipv6 network with jumbo frames enable on either end of the transmission, and a device in the middle with jumbo frames disabled, etc... the packets would drop.
Top Expert 2010

"the lack of support for packet fragmentation in IPv6"

there is packet fragmentation in IPv6, it is just not done on intermediary devices, only on end-nodes; meaning the end-nodes have the option to add fragmentation headers. I think it is important that you understand that you are mixing apples and oranges, a frame, is a layer 2 PDU and IP is Layer 3. A frame by default on most layer 2 switches support up to 1500 bytes and IP at layer 3 can support the data (payload), typically referred to as MTU at 1500 bytes. So a packet traversing the router can only have max of 1500 bytes. So, it is not so much that you have to worry about routers, but switches as well. If you change the MTU on the host size, you must change it end to end on all devices in your network.

Top Expert 2011

"you are mixing apples and oranges"

I agree rfc118. You notice how I worded my answer in relation to the question? ;-)

Yes, IPv6 is supported as well as Jumbo frames