Re: [rtcweb] Let's define the purpose of WebRTC

Eric Rescorla <ekr@rtfm.com> Mon, 07 November 2011 13:57 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 7 Nov 2011 05:50:20 -0800
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To: Hadriel Kaplan <HKaplan@acmepacket.com>
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Subject: Re: [rtcweb] Let's define the purpose of WebRTC
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On Sun, Nov 6, 2011 at 7:20 PM, Hadriel Kaplan <HKaplan@acmepacket.com> wrote:
>>> IMHO, if a web service doesn't want to take, or cannot take, the hit
>>> for SRTP, WebRTC is not the appropriate solution for such a service.
>>
>> I'm exceedingly unsympathetic to the claim that SRTP is too slow. This
>> is precisely the claim that was made about TLS for years, but measurements
>> (see Langley and Modadugu's Overclocking SSL talk at Velocity) show
>> that that's not really true.
>
> Who said "too slow"?  There *is* an extra round-trip or two involved I presume, if we're talking DTLS-SRTP, but no I didn't mean that as a "hit".  I just meant the extra computing cycles for SRTP being a "hit".  For WebRTC-to-WebRTC I don't think that matters at all.  For WebRTC-to-media-server it might, for a free game app or greeting card app that don't care about it to begin with, and which use plaintext HTTP to begin with.

Sorry, I didn't mean to put words in your mouth. Performance measurements
of HTTP versus HTTPS in modern Web environments suggest that the additional
load for HTTPS is not significant. Do you have evidence that the situation is
different for SRTP versus RTP?

-Ekr

> (this isn't a big deal regardless - just something to think about whether we care or not)
>
> -hadriel
>
>