On 8/18/08 10:31 PM, actech allegedly wrote: > Mr.Brim, > > Thank you for your comments for 16th version of ATARC payload format. > We agree with almost of your comments, and modified the draft > according to that. However, for one issue (regarding on Fragment Number), > we did not change the draft by the reason described below. > > You can see the latest version of ATRAC payload format as > draft-ietf-avt-rtp-atrac-family-17.txt. > If you have further comments on the draft, please let us know. > > Regards, > > Jun
Thank you, Jun. My response is below ... > > ---------------------------------------------------- >> > 5.3.1 Usage of ATRAC Header Section >> > >> > > Fragment Number (FrgNo): 3 bits >> > > In the event of data fragmentation, this value is one for the >> > > first packet, and increases sequentially for the remaining >> > > fragmented data packets. This value SHOULD be zero for an >> > > unfragmented frame. >> > >> > Earlier it was said: "The ATRAC codec can handle very large frames. As >> > most IP networks have significantly smaller MTU sizes than the frame >> > sizes ATRAC can handle ...". If there can be such a significant >> > difference -- and if you want to allow for larger frames in the future >> > -- is there special handling for when this 3-bit counter rolls over >> > (more than 7 fragments)? If not, at least mention that you do not >> > expect it to roll over -- or that you expect the receiver to be able to >> > handle rollovers. > > In ATRAC specification, it is described that supported bit-rate is > up to 1.4Mbps. It corresponds to approximately 7500bytes/frame. > So 3-bit counter is sufficient for expressioning Fragment Number, > as far as the MTU size is 1500bytes. I still make a friendly suggestion that you document that dependency, because if there is an extension to the ATRAC specification in the future to support a higher bit rate, this protocol might break. Scott _______________________________________________ Gen-art mailing list Gen-art@ietf.org https://www.ietf.org/mailman/listinfo/gen-art
