Investigate channel receivers

[cBournhonesque]

Take a look at channel receivers to see if they are correct.

I think reliability should only be the concern of the sender, and ordering (sequenced, ordered, unordered) should only be the concern of the receiver. So why do we have stuff like sequenced_reliable and sequenced_unreliable? Is it just to discard fragments?

I'm wondering if there's an issue here.

Similarly, it looks like unordered_reliable doesn't make sense; the sender makes sure that the channel is reliable by re-sending stuff if no acks