Re: [hybi] frame length encoding

[John Tamplin <[e-mail]>]

On Sun, Aug 22, 2010 at 5:53 AM, Shelby Moore <[e-mail]> wrote:

> I forgot that I had already mentioned in this thread that we only need to
> keep 1 reserved bit free, so that we can always add another bit as needed,
> by allocating that 1 bit to signal there is an extra byte.  Repeat in next
> byte, and so on...
>
> So we don't need the extra byte now, unless we see an extension now that
> needs that many bits.
>
> Any one disagree?


Yes, I agree that as long as we don't use our last reserved bit for
something besides "more reserved bits", we can arbitrarily extend the
protocol.  However, we have several things which we know we want to
implement as extensions in short order - multiplexing and compression among
them, and perhaps additional metadata.  If we only have one spare bit in the
base protocol, then that means we must define it as the "more reserved bits"
flag, and we will then be paying a cost for what are expected to be common
extensions.  Also, note that we would have to negotiate adding these
reserved bytes in the handshake for interoperability with base protocol
implementations.

-- 
John A. Tamplin
Software Engineer (GWT), Google