TCP is one of the great works of the human mind, but it did not envision the dominance of semiconnected networks.

convolvatron 17 hours ago | parent | next [-]

if you went back to 1981 and said 'yeah, this is great. but what we really want to do is not have an internet, but kind of a piecewise internet. instead of a global address we'll use addresses that have a narrower scope. and naturally as consequence of this we'll need to start distinguishing between nodes that everyone can reach, service nodes, and nodes that no one can reach - client nodes. and as a consequence of this we'll start building links that are asymmetric in bandwidth, since one direction is only used for requests and acks and not any data volume.'

they would have looked at you and asked straight out what you hoped to gain by making these things distinguished, because it certainly complicates things.

	▲	FrankWilhoit 14 hours ago \| parent [-]
		Wireless networks are always going to have asymmetries of transmit power. Everything flows from that. ALOHAnet was 1971.

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cpach 19 hours ago | parent | prev [-]

Are you referring to NAT?

	▲	FrankWilhoit 14 hours ago \| parent [-]
		No. TCP likes zero packet loss (connected), and it understands 100% packet loss (disconnected). Its weakness is scenarios (semiconnected) in which packet loss is constantly fluctuating between substantial and nearly-total. It doesn't know what is going on, and it may cope or it may not, because its designers did not envision a future in which most networks have a semiconnected last mile; but that is where we are. Without things like forward error correction, TCP would be nearly useless over wireless. It is interesting to envision a layer-4 protocol that would incorporate FEC-like capabilities.