Re: [arch-d] FYI: closure of the IAB Stack Evolution program

[Christian Huitema <[e-mail]>]

On 8/25/2019 6:59 AM, Fernando Gont wrote:

> I agree with the above, still, the reason for which QUIC employs UDP
> (rather than doing mux/demux by itself) is because you can't deploy new
> transport protocols on the Internet.


I think we are getting caught in disputes over vocabulary. Two things
are true at the same time:

1) We cannot send packets in which the IP protocol or IPv6 payload type
is set to a different value than TCP or UDP and expect them to reach
destinations across the Internet.

2) QUIC, BitTorrent and SCTP demonstrate that you can run a protocol on
top of UDP that has all the characteristics of a classic transport
protocol, including error recovery and congestion control. ( QUIC can
perform mux/demux by itself, using the "connection ID" field, but most
deployments refrain from using multiple layers of multiplexing.)

Using UDP causes 8 bytes of overhead per packet, which is unfortunate.
You may call that a middle-box tax if you want. But as long as you are
willing to pay that tax, you can of course deploy new transmission
control protocols over the Internet. Most people will call them
transport protocols.

-- Christian Huitema