On Dec 5, 2017, at 4:47 AM, Bruno Verstuyft <bruno.verstu...@gmail.com> wrote:
> 2017-12-04 22:21 GMT+01:00 Guy Harris <g...@alum.mit.edu>: > >> On Nov 16, 2017, at 1:21 AM, Bruno Verstuyft <bruno.verstu...@gmail.com> >> wrote: >> >>> we put the specification of the XRA header online. >> >> The MAC document speaks of "logical" upstream and downstream channels; are >> those what the "Downstream Channel ID" and "Upstream Channel ID" TLVs refer >> to? >> > Yes, from the MULPI spec: > Logical (Upstream) Channel: A MAC entity identified by a unique channel ID > and for which bandwidth is allocated by an > associated MAP message. A physical upstream channel may support multiple > logical upstream > channels. The associated UCD and MAP messages completely describe the > logical channel. You might want to say "ID of downstream *logical* channel" in the remarks for "Downstream Channel ID"; the remarks for "Upstream Channel ID" already say "logical upstream channel" (is it best to say "logical XXX channel" or "XXX logical channel"?). >> To what do the start and stop minislots in the "Minislot ID" TLV refer? > > These are the minislots, relative in an OFDMA frame. The minislot with the > lowest subcarriers has id 0. So those are the minislots from section 7.4.1 "Signal Processing Requirements" of the PHY specification? >> What do the "Symbol ID", "Burst ID", and "Subplot ID" TLVs contain? > > Symbol ID is a number assigned to each symbol by our hardware. This is > mainly used for timing calculations. It can also be used to visualize the > correlation between NCP (Next Codeword Pointers) and the corresponding > downstream data packets. So to which symbol in the packet does that refer? > Burst ID is used to map mac frames to the corresponding databurst. A > databurst can e.g. contain a segment:(see MULPI 7.2.4 > Continuous Concatenation and Fragmentation). This means a segment can > contain multiple Mac frames, or a Mac frame can be spread over multiple > segments. In our sniffer, we extract these Mac frames from the segments. To > save the information of which Mac frame belongs to which segment (or > multiple segments), we use the Burst ID: each data burst gets a unique > Burst ID. In the Mac Frame the "Burst Info"/"Burst ID reference" is used to > reference these Burst IDs. So your sniffer assigns the Burst IDs? There's a variable-length "Burst ID" field and a "Burst ID Reference" field. Does the "Burst ID" field contain a single burst ID? If so, to which burst was that ID assigned? And what does the "Burst ID Reference" field contain? >> Does the SID TLV contain the Service Identifier for the service flow in >> which the packet was sent? > > Yes You might want to spell out "Service Identifier" in the remarks. >> Does the IUC TLV contain the Interval Usage Code for the burst if the >> packet is a burst? > > Yes You might want to spell out "Interval Usage Code" in the remarks. _______________________________________________ tcpdump-workers mailing list tcpdump-workers@lists.tcpdump.org https://lists.sandelman.ca/mailman/listinfo/tcpdump-workers
