I wouldn't presume to accuse the engineers behind SPDY of ignoring the existing work in the space. I did take exception to the immediate parent's dismissive and inaccurate characterization of SCTP. That protocol is a worthy attempt to solve real problems at the most technically desirable layer. SPDY looks to be a good piece of engineering, inventing only as much as necessary to achieve a well defined benefit. I cannot fault its creators for that.
I stand behind my assertion that SPDY will succeed at the expense of SCTP. There are finite resources available for such work and those two protocols are in direct competition. After all the investment by browser implementors, web server vendors, proxies, reverse proxies, etc to support the former, can you really see any interest in doing so all over again for only modest direct benefit? If you succeed, then that constituency will have been largely satisfied. The web will indeed be better off – no small thing! And it will be good enough. Good enough in the same way that HTTPS is good enough. The protocol is sufficiently extensible that new ciphers have been deployed without breaking older implementations, but the true weaknesses lie in the fundamentally flawed nature of the CA institution that it spawned: a social problem, one not readily susceptible to technical improvement. Only now that the weakness in the CA system have been exploited and publicized has there been much appetite for any innovation in that space whatsoever. DNSSec is only just now percolating up through the resolver to applications – how long before we can rely on a sound technical foundation for transport crypto such as the HIP protocol aims to provide? The shortcuts taken today will linger to haunt future generations.
Engineers solve real problems, affording us real, practical benefit. I get that. Please forgive me that I am sad that solving these problems one niche at a time means that we can't seem to pull together towards a general solution for a broader benefit. I don't want it to just work: I wish for the foundations to be sound.