[ih] Why did DCCP fail to gain traction?

[Bless, Roland (TM)]

Hi,

my perception was that at the time DCCP was designed,
there was a fear that especially an increasing amount of
multimedia streams may cause congestion problems and
it would be better to to solve them in a single protocol
rather than letting the application developers do it
  "somehow" (and maybe neglecting ECN support etc.).
See also the section 2 of RFC4340
https://datatracker.ietf.org/doc/html/rfc4340#section-2

However, given the development of WebRTC and DASH,
people used rather their own application-specific
congestion control mechanisms instead. For example,
WebRTC used more fine-grained RTCP-based feedback
(see also RFC8888) and there were other approaches
developed in the (concluded) RMCAT WG
(https://datatracker.ietf.org/wg/rmcat/about/) as well
such as NADA (RFC8698) and SCReAM (RFC8298).

The reasons why DCCP had seen no real deployment are
probably manifold, but I guess that NAT/FW traversal
for DCCP as well as the easier development and change
process in the user space contributed to this
(as others noted, this also helped QUIC development and
was a deliberate design choice).

FWIW, there has been recent work in the IETF on Multipath-DCCP
https://datatracker.ietf.org/doc/rfc9897/
to support a special use case for providing an MP-DCCP proxy
inside a provider network. The idea was to also support
QUIC and other UDP-based protocols.

So I disagree that QUIC development hindered DCCP
deployment already,
the work on Media over QUIC (MOQ) started only 2022.

Regards,
  Roland

On 03.10.26 at 18:26 John Kristoff via Internet-history wrote:
> DCCP (IETF RFC 4330) is/was a relatively new transport in Internet
> history. I don't think it ever really saw much, if any, deployment or
> support in applications. It was removed from the Linux kernel last year.
> 
> Was it too late, too complex, too little, or just deemed unnecessary
> given available alternatives such as QUIC?  I don't recall seeing
> much discussion about why it failed to gain traction and I'm interested
> to hear what the collective wisdom of this group might have to say about
> that.