HTTP/2: Settings

[shirhatti]

HTTP/2 allows for both the client and the server to send a SETTINGS frame to set preferences and constraints on how endpoints communicate.

The spec currently lists 6 supported SETTINGS Parameters

• SETTINGS_HEADER_TABLE_SIZE (0x1) Make hpack header table size configurable #2816
• SETTINGS_ENABLE_PUSH (0x2) - N/A
• SETTINGS_MAX_CONCURRENT_STREAMS (0x3) Limit concurrent HTTP/2 Streams per connection #2815
• SETTINGS_INITIAL_WINDOW_SIZE (0x4) Make connection and stream windows configurable #2814
• SETTINGS_MAX_FRAME_SIZE (0x5) Make max frame size configurable #2817
• SETTINGS_MAX_HEADER_LIST_SIZE (0x6) Make max header list size configurable #2818
• Initial handshake timeout - time to Receive the connection preface "PRI *
  HTTP/2.0\r\n\r\nSM\r\n\r\n" https://tools.ietf.org/html/rfc7540#section-3.5. Or will the KeepAlive timeout apply best here? This would still be after the TLS handshake timeout. Add timeout for initial handshake #2900
• Settings ack timeout https://github.com/aspnet/KestrelHttpServer/issues/2901

For each setting We need to

• Pick reasonable defaults and constraints on permissible values for each of these settings parameters.
• Expose these settings via Kestrel Options

[Tratcher]

edit moved to top

Consider also:

• Initial handshake timeout - time to Receive the connection preface "PRI *
  HTTP/2.0\r\n\r\nSM\r\n\r\n" https://tools.ietf.org/html/rfc7540#section-3.5. Or will the KeepAlive timeout apply best here? This would still be after the TLS handshake timeout.
• Settings ack timeout

[muratg]

Remaining limits are tracked on individual bugs.