# Shepherd Writeup for draft-ietf-httpbis-tunnel-protocol
## 1. Summary
Mark Nottingham is the document shepherd; Barry Leiba is the responsible Area
Director.
This specification allows HTTP CONNECT requests to indicate what protocol will
be used within the tunnel once established, using the ALPN header field.
Its intended status is Proposed Standard.
## 2. Review and Consensus
This document was brought to the Working Group as a result of work in WebRTC
and related groups, to satisfy a requirement there.
It was discussed in WG meetings as well as on-list, with a broad selection of
participants.
Some participants were concerned that the mechanism is not verifiable; i.e., an
intermediary does not have any assurance that the protocol in use inside an
encrypted tunnel is actually advertised. However, we found that this is
acceptable, because of the nature of the mechanism; it is not designed to
provide such assurances, but instead allow coordination between cooperating (or
semi-cooperating) actors.
Other participants were concerned because of confusion about whether this
mechanism can be used when TLS is not in use, and the ambiguity that the use of
ALPN entails when it is not. We resolved this by explicitly linking it to ALPN,
so that the protocol identifier can nominate whether encryption is in use.
To our knowledge, this specification has not been implemented yet. This is not
surprising, given the nature of the extension.
## 3. Intellectual Property
Each author has stated that their direct, personal knowledge of any IPR related
to this document has already been disclosed.
No IPR declarations have been made.
## 4. Other Points
Idnits reports a few problems, but they are spurious.
IANA Considerations does not precisely identify the registry being entered
into; the next draft will correct this.