IPv4 lets the MTU get as low as 68 (but you&#x27;re only sending 8 bytes of data per packet); IPv6 prevents it from getting any lower than 1280, but permits &quot;link-specific fragmentation and reassembly&quot; as long as IPv6 itself doesn&#x27;t see any smaller fragments.<p>IPv6 also permits (but does not require) jumbograms that make full use of the 32-bit packet size field, but across a wireless link, having to retransmit 4 GB at a time seems like a bad plan... this only seems useful for short-distance wired connections among hosts that know they&#x27;ve got a quality cable between them.