Re: QSPEC TMOD and packet header overhead
Gerald Ash <[email protected]>
| Newsgroups | gmane.ietf.nsis |
|---|---|
| Message-ID | <[email protected]> |
Hi Roland, I think your examples are fine (although overhead for PPP header and perhaps MPLS labels might also be included). However, as stated at the beginning of Section 5.2 (QSPEC Parameter Coding): "The references in the following sections point to the normative procedures for processing the QSPEC parameters and sub-parameters." In the case of TMOD-1 and TMOD-2, the normative references are RFC 2210 and RFC 2215. In particular, Section 3.1 in RFC 2210 and Section 3.6 in RFC 2215 give the necessary guidance on setting the token bucket parameters. IMO the QSPEC document isn't the place to give detailed examples of how to set these QSPEC parameters, or any other QSPEC parameters, beyond what is contained in the normative references. Jerry Roland Bless <[email protected]> wrote: Hi, probably a dumb question, but Max Laier and I could not find any guidance on this in the qspec draft: I guess that the TMOD-1 r parameter in draft-ietf-nsis-qspec-20 specifies the number of bytes/s for IP packets, including any IP headers. Now consider a mobile node that adds extra overhead to its data packets due to the mobility headers etc. This could be significant for VoIP packets. So in this case the applications has to increase r depending on the packet rate and m must be increased, too? As another example: if the application communicates via IPv4 it has to specify for a normal PCM codec VoIP traffic: r=50*(20+8+12+160)=10,000 bytes/s [packet every 20ms,IP+UDP+RTP+payload], m=200 bytes, b= 2000 bytes, p=very high (allowing a burst of 10 packets) and when communication via IPv6 r=50*(40+8+12+160)=11,000 bytes/s, m=220 bytes, b= 2200 bytes Is this correct? Would it make sense to provide a little guidance on this and an example in the QSPEC? Regards, Roland _______________________________________________ nsis mailing list [email protected] https://www.ietf.org/mailman/listinfo/nsis __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ nsis mailing list [email protected] https://www.ietf.org/mailman/listinfo/nsis