Commands and data are transferred on the buses using packets with three-word headers.

A network design can achieve two major results by using packets: error detection and multiple host addressing.

Latency for data connections is around 1800 ms round-trip, using small packets.

Rather than using variable length frames or packets, data is carried in fixed size cells.

For a protocol using small packets, this delay can be larger than the time needed to send a packet.

And some routers will not, because there has been a history of fragmentation attacks, different ways of using fragmented packets to get through firewalls.

One technique, for example, uses fragmented packets that can pass through unexamined because the port numbers aren't present in the first fragment.

It can now also be easily home-made using instant packets.

And critical instrumentation should use redundant packets, with checksums for validity.

I've even been known to make them myself, using boxes and packets just like Charles and Jenny used.