Aurora 64/66 Input
- Introduction to 10 GbE 64b/66b: 10GbE_CI49.pdf
- See esp page 23 on for scrambler/gearbox details
- 8b10b vs 6466 coding: 8B10B_Coding.pdf
On-board RAM
DAQ output estimate for one DTC is about 400 Gbit/s
Maximum (component) DDR4 speed is 2400 Mb/s
So, R/W of all data would require 333 bits and is therefore completely excluded. We will not be buffering the data in RAM.
DAQ Outputs
DAQ document (DocDBhttps://cms-docdb.cern.ch/cgi-bin/DocDB/ShowDocument?docid=13356 DocDB]) describes various DTH modules.
DTH400: 16 (or 24) inputs (25 or 16 Gbps) and 400 Gb/s output
DTH1200: 48 (or 72) inputs (25 or 16 Gbps) and 1200 Gb/s output
In the document, Table 2.2 says we have the following for the inner tracker:
4 BE crates 2 DTH1200 per crate 8 DTH1200 per subdet 24 D2S links per crate 96 D2S links per subdet
The document also says that there are 4 crates with 6 boards per crate. They calculate the output b/w based on 72 inputs at half-capacity or 72x10/2 = 360 Gb/s.
This requires 4x100 Gb/s output per board, or 16 links at 25Gb/s. The DAQ document does not address whether these are bidirectional links, but I think we can assume a minimum of one return fiber per 4 output fibers.
