Jane Avriette > Net-TDMA-0.2 > Net::TDMA::Day::Epoch::Frame::Slot



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The TDMA slot is the most basic component of the network. It is roughly 7 miliseconds long.


        my $tdma_slot = Net::TDMA::Day::Epoch::Frame::Slot->new(); # no arguments

A pinch of reality

The amount of data you can fit into it depends upon your line speed, and how fast you can feed your data into your data structures. There's no reason you couldn't transmit a two gigabyte tiff in every slot, but you would need both the processor power necessary to serialize that object, as well as the line speed will have to be in excess of three terabytes a second.

In practice, the size of a slot is governed by the protocol, and is often on the order of a hundred or a few hundred bits. Room is left for checksum information, generally. There are also two additional pieces, which are valuable to cryptographers: jitter and propagation. Jitter is "dead time" used at the beginning of a slot, and propagation is more "dead time" used at the end of a slot. So if we have a hundred bits of bandwidth per slot, we may choose to vary our jitter and propagation values so that somebody listening is unable to tell when the messages begin and end.

Because this is constant for the protocol, this data is set in the Constants package.

Your object is a blessed array ref, but with the Constants package, you can add to it just about anything perl can create.


        Alex J. Avriette
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