Hi, As per the spesification I dont' see any requirement that the SETTINGS Frame has to be transmitted first. On Fri, Jul 29, 2016 at 10:58 AM, Cory Benfield <cory@lukasa.co.uk> wrote: > > On 29 Jul 2016, at 09:31, Wesley Oliver <wesley.olis@gmail.com> wrote: > > I see that the documentation say nothing about how the negotiation is to > happen. > > > In this case, a setting is necessary: a header field is not good enough. > This is because this functionality requires that all entities on the > connection (intermediaries too) understand the change this makes to the H2 > stream state machine. That works when transmitted on a SETTINGS frame > because each hop of the connection that is actually participating in the H2 > connection needs to look at the SETTINGS frame and respond appropriately. > Header fields, however, may be passed through to the endpoint, which leads > to a situation where the client and server can both do this but the > intermediary cannot, and the intermediary mangles or otherwise terminates > the connection. > > Otherwise it would have to wait for the settings frame communication to > have proceed first, > which then introduce latency for client side and would result in the > server having to block > before it could response, clearly a degradation of performance. > > > The server needs to do this anyway. The start of a HTTP/2 connection > involves both parties sending SETTINGS frames. The server cannot receive > the first HEADERS frame without having previously received a SETTINGS from > the client that would be offering support for this functionality. > > Cory > > -- -- Web Site that I have developed: http://www.swimdynamics.co.za Skype: wezley_oliver MSN messenger: wesley.olis@gmail.com
Received on Friday, 29 July 2016 11:13:30 UTC