Re: RFC4815 no TS bits
Jer-ming Lin <[email protected]> Thu, 04 Feb 2010 18:34:04 +0800
| Newsgroups | gmane.ietf.rohc |
|---|---|
| Message-ID | <[email protected]> |
Dear Sir, Quoting Carl Knutsson <[email protected]>: >> .. >> TS_STRIDE and the relationship of delta_TS. Is that right? > > No, the compressor must first establish the TS_STRIDE by sending it > as-is together with unscaled TS. From those two values, TS_SCALED and > TS_OFFSET can be derived and used for later for compression. > After establishing the TS_STRIDE and TS_OFFSET, the compressor sends scaled TS bits or no TS bits if scaled TS has the relationship of "delta_TS=delta_SN*default-slope(TS)." For performance issue, if the scaled TS(derived from unscaled TS/TS_STRIDE) also have the relationship of delta_TS in consecutive IR/IR-DYN/UOR-ext3 packets. Can the compressor send no-TS bits directly after the establishing packets? The RFC did not mention this. I think this can reduce the compressed header size since no-TS bits are sent. For example, SN, TS, TS_STRIDE, scaled TS, Type, transmit TS bits, 1, 26189, 280, 93, IR, 32 2, 26469, 280, 94, IR, 32 3, 26749, 280, 95, IR, 32 4, 27029, 280, 96, UO-0, 0 The first, sencond, third construct the TS_STRIDE and the relationship of delta_TS. The forth cand send no-TS bits. Sincerely yours, Jer-ming ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program.