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19 Transport Layer and O-RAN Fronthaul Protocol Implementation
20 ===========================================================
26 This chapter describes how the transport layer and O-RAN Fronthaul
27 protocol are implemented.
34 Figure 8 presents an overview of the O-RAN Fronthaul process.
36 .. image:: images/ORAN-Fronthaul-Process.jpg
38 :alt: Figure 8. O-RAN Fronthaul Process
40 Figure 8. O-RAN Fronthaul Process
42 The O-RAN library provides support for transporting In-band and
43 Quadrature (IQ) samples between the O-DU and O-RU within the O-RAN
44 architecture based on functional split 7.2x. The library defines the
45 O-RAN packet formats to be used to transport radio samples within Front
46 Haul according to the O-RAN Fronthaul specification. It provides
47 functionality for generating O-RAN packets, appending IQ samples in the
48 packet payload, and extracting IQ samples from O-RAN packets.
50 Note: The E Miantenance release version of the library supports U-plane and C-plane only. It is ready to be used in the PTP synchronized environment.
52 Note: Regarding the clock model and synchronization topology, configurations
53 C1 and C3 of the connection between O-DU and O-RU are the only
54 configurations supported in this release of the O-RAN implementation.
56 Note: Quality of PTP synchronization with respect to S-plane of O-RAN
57 Fronthaul requirements as defined for O-RU is out of the scope of this
58 document. PTP primary and PTP secondary configuration are expected to satisfy
59 only the O-DU side of requirements and provide the “best-effort” PTP primary for
60 O-RU. This may or may not be sufficient for achieving the end to end
61 system requirements of S-plane. Specialized dedicated NIC card with
62 additional HW functionality might be required to achieve PTP primary
63 functionality to satisfy O-RU precision requirements for RAN deployments
66 .. image:: images/Configuration-C1.jpg
68 :alt: Figure 9. Configuration C1
70 Figure 9. Configuration C1
73 .. image:: images/Configuration-C3.jpg
75 :alt: Figure 10. Configuration C3
77 Figure 10. Configuration C3
82 The O-RAN Fronthaul specification defines a list of mandatory
83 functionality. Not all features defined as Mandatory for O-DU are
84 currently supported to fully extended. The following tables contain
85 information on what is available and the level of validation performed
88 Note. Cells with a red background are listed as mandatory in the
89 specification but not supported in this implementation of O-RAN.
91 Table 7. ORAN Mandatory and Optional Feature Support
93 +-----------------+-----------------+-----------+----------------+
94 | Category | Feature | O-DU | Support |
96 +=================+=================+===========+================+
97 | RU Category || Support for | Mandatory | Y |
98 | || CAT-A RU (up to| | |
101 | +-----------------+-----------+----------------+
102 | || Support for | | Y |
103 | || CAT-A RU (> 8 | | |
106 | +-----------------+-----------+----------------+
107 | || Support for | Mandatory | Y |
109 | || (precoding in | | |
111 +-----------------+-----------------+-----------+----------------+
112 | Beamforming || Beam Index | Mandatory | Y |
114 | +-----------------+-----------+----------------+
115 | || Real-time BF | Mandatory | Y |
117 | +-----------------+-----------+----------------+
118 | || Real-Time | | N |
119 | || Beamforming | | |
120 | || Attributes | | |
121 | +-----------------+-----------+----------------+
122 | | UE Channel Info | | N |
123 +-----------------+-----------------+-----------+----------------+
124 | Bandwidth || Programmable | Mandatory | Y |
125 | Saving || staticbitwidth | | |
126 | || Fixed Point IQ | | |
127 | +-----------------+-----------+----------------+
128 | || Real-time | | Y |
129 | || variable-bit | | |
131 | +-----------------+-----------+----------------+
132 | | Compressed IQ | | Y |
133 | +-----------------+-----------+----------------+
134 | || Block floating | | Y |
136 | || compression | | |
137 | +-----------------+-----------+----------------+
138 | || Block scaling | | N |
139 | || compression | | |
140 | +-----------------+-----------+----------------+
142 | || compression | | |
143 | +-----------------+-----------+----------------+
144 | || modulation | | Y |
145 | || compression | | |
146 | +-----------------+-----------+----------------+
147 | || beamspace | | Y |
148 | || compression | | |
149 | +-----------------+-----------+----------------+
150 | || Variable Bit | | Y |
152 | || Channel (per | | |
153 | || data section) | | |
154 | +-----------------+-----------+----------------+
156 | || configuration | | |
157 | || of U-Plane IQ | | |
158 | || format and | | |
159 | || compression | | |
161 | +-----------------+-----------+----------------+
162 | || Use of symInc | | N |
163 | || flag to allow | | |
165 | || symbols in a | | |
166 | || C-Plane section| | |
167 +-----------------+-----------------+-----------+----------------+
168 | Energy Saving || Transmission | | N |
170 +-----------------+-----------------+-----------+----------------+
171 | O-DU - RU || Pre-configured | Mandatory | Y |
172 | Timing || Transport Delay| | |
174 | +-----------------+-----------+----------------+
175 | || Measured | | N |
177 | || Method (eCPRI | | |
179 +-----------------+-----------------+-----------+----------------+
180 | Synchronization | G.8275.1 | Mandatory | Y (C3 only)|
182 | +-----------------+-----------+----------------+
184 | +-----------------+-----------+----------------+
185 | | GNSS based sync | | N |
186 | +-----------------+-----------+----------------+
188 +-----------------+-----------------+-----------+----------------+
189 | Transport | L2 : Ethernet | Mandatory | Y |
191 | +-----------------+-----------+----------------+
192 | || L3 : IPv4, IPv6| | N |
193 | || (CUS Plane) | | |
194 | +-----------------+-----------+----------------+
195 | || QoS over | Mandatory | Y |
197 | +-----------------+-----------+----------------+
198 | || Prioritization | | N |
199 | || of different | | |
200 | || U-plane traffic| | |
202 | +-----------------+-----------+----------------+
203 | || Support of | | N |
204 | || Jumbo Ethernet | | |
206 | +-----------------+-----------+----------------+
207 | || eCPRI | Mandatory | Y |
208 | +-----------------+-----------+----------------+
209 | || support of | | N |
211 | || concatenation | | |
212 | +-----------------+-----------+----------------+
213 | | IEEE 1914.3 | | N |
214 | +-----------------+-----------+----------------+
215 | || Application | Mandatory | Y |
216 | || fragmentation | | |
217 | +-----------------+-----------+----------------+
218 | || Transport | | N |
219 | || fragmentation | | |
220 +-----------------+-----------------+-----------+----------------+
221 | Other || LAA LBT O-DU | | N |
222 | || Congestion | | |
223 | || Window mgmt | | |
224 | +-----------------+-----------+----------------+
225 | || LAA LBT RU | | N |
226 | || Congestion | | |
227 | || Window mgm | | |
228 +-----------------+-----------------+-----------+----------------+
230 Details on the subset of O-RAN functionality implemented are shown in
233 Level of Validation Specified as:
236 - C: Completed code implementation for O-RAN Library
238 - I: Integrated into Intel FlexRAN PHY
240 - T: Tested end to end with O-RU
242 Table 8. Levels of support
244 +------------+------------+------------+------------+-----+-----+-----+
245 | Category | Item | Status | C | I | T |
246 +============+============+============+============+=====+=====+=====+
247 | General || Radio | NR | N/A | N/A | N/A |
248 | || access | | | | |
249 | || technology | | | | |
250 | || (LTE / NR) | | | | |
251 | +------------+------------+------------+-----+-----+-----+
252 | || Nominal || 15 | Y | Y | N |
253 | || sub-carrier || /30/120KHz| | | |
254 | || spacing | | | | |
255 | +------------+------------+------------+-----+-----+-----+
256 | | FFT size || 512/1024 | Y | Y | N |
257 | | || /2048/4096| | | |
258 | +------------+------------+------------+-----+-----+-----+
259 | || Channel || 5/10 | Y | Y | N |
260 | || bandwidth || /20/100Mhz| | | |
261 | +------------+------------+------------+-----+-----+-----+
262 | || Number of | 12 | Y | Y | N |
264 | || (Component | | | | |
265 | || Carriers) | | | | |
267 | +------------+------------+------------+-----+-----+-----+
268 | || RU | A | Y | Y | N |
269 | || category | | | | |
270 | +------------+------------+------------+-----+-----+-----+
271 | | TDD Config || Supported | Y | Y | N |
272 | | || Flexible | | | |
273 | +------------+------------+------------+-----+-----+-----+
274 | || FDD | Supported | Y | Y | N |
275 | || Support | | | | |
276 | +------------+------------+------------+-----+-----+-----+
277 | || Tx/Rx | Supported | Y | Y | N |
278 | || switching | | | | |
279 | || based on | | | | |
281 | || Direction' | | | | |
282 | || field of | | | | |
283 | || C-plane | | | | |
284 | || message | | | | |
285 | +------------+------------+------------+-----+-----+-----+
286 | || IP version | N/A | N/A | N/A | N/A |
288 | || Management | | | | |
289 | || traffic at | | | | |
290 | || fronthaul | | | | |
291 | || network | | | | |
293 +------------+-------------------------+------------+-----+-----+-----+
294 | PRACH || One Type 3 | Supported | Y | Y | N |
295 | || message | | | | |
296 | || for all | | | | |
297 | || repeated | | | | |
299 | || preambles | | | | |
300 | +-------------------------+------------+-----+-----+-----+
301 | || Type 3 | 1 | Y | Y | N |
302 | || message | | | | |
304 | || repeated | | | | |
306 | || preambles | | | | |
307 | +-------------------------+------------+-----+-----+-----+
308 | || timeOffset | Supported | Y | Y | N |
309 | || including | | | | |
310 | || cpLength | | | | |
311 | +-------------------------+------------+-----+-----+-----+
312 | | Supported | Supported | Y | Y | N |
313 | +-------------------------+------------+-----+-----+-----+
314 | || PRACH | Supported | Y | Y | N |
315 | || preamble | | | | |
316 | || format | | | | |
318 | || number | | | | |
319 | || (number of | | | | |
320 | || occasions) | | | | |
322 +------------+-------------------------+------------+-----+-----+-----+
323 || Delay || Network | Supported | Y | Y | N |
324 || management|| delay | | | | |
325 | || determination | | | | |
326 | +-------------------------+------------+-----+-----+-----+
327 | || lls-CU | Supported | Y | Y | N |
328 | || timing | | | | |
329 | || advance | | | | |
331 | +-------------------------+------------+-----+-----+-----+
332 | || Non-delay || Not | N | N | N |
333 | || managed || supported | | | |
334 | || U-plane | | | | |
335 | || traffic | | | | |
337 +------------+-------------------------+------------+-----+-----+-----+
338 || C/U-plane || Transport | Ethernet | Y | Y | N |
339 || Transport || encapsulation | | | | |
340 | || (Ethernet IP) | | | | |
341 | +-------------------------+------------+-----+-----+-----+
342 | || Jumbo | Supported | Y | Y | N |
343 | || frames | | | | |
344 | +-------------------------+------------+-----+-----+-----+
345 | || Transport | eCPRI | Y | Y | N |
346 | || header | | | | |
347 | || (eCPRI RoE) | | | | |
348 | +-------------------------+------------+-----+-----+-----+
349 | || IP version | N/A | N/A | N/A | N/A |
351 | || Transport | | | | |
352 | || header is | | | | |
353 | || IP/UDP | | | | |
354 | +-------------------------+------------+-----+-----+-----+
355 | || eCPRI || Not | N | N | N |
356 | || Concatenation || supported | | | |
358 | || Transport | | | | |
359 | || header is | | | | |
361 | +-------------------------+------------+-----+-----+-----+
362 | || eAxC ID | 4 \* | Y | Y | N |
363 | || CU_Port_ID | | | | |
364 | || bitwidth | | | | |
365 | +-------------------------+------------+-----+-----+-----+
366 | || eAxC ID | 4 \* | Y | Y | N |
367 | || BandSector_ID | | | | |
368 | || bitwidth | | | | |
369 | +-------------------------+------------+-----+-----+-----+
370 | || eAxC ID | 4 \* | Y | Y | N |
372 | || bitwidth | | | | |
373 | +-------------------------+------------+-----+-----+-----+
374 | || eAxC ID | 4 \* | Y | Y | N |
375 | || RU_Port_ID | | | | |
376 | || bitwidth | | | | |
377 | +-------------------------+------------+-----+-----+-----+
378 | | Fragmentation | Supported | Y | Y | N |
379 | +-------------------------+------------+-----+-----+-----+
380 | || Transport | N/A | N | N | N |
381 | || prioritization | | | | |
382 | || within | | | | |
383 | || U-plane | | | | |
384 | +-------------------------+------------+-----+-----+-----+
385 | || Separation | Supported | Y | Y | N |
387 | || C/U-plane | | | | |
389 | || M-plane | | | | |
390 | +-------------------------+------------+-----+-----+-----+
391 | || Separation || VLAN ID\ | Y | Y | N |
392 | || of C-plane || and/or | | | |
393 | || and || eCpri | | | |
394 | || U-plane || Messagge | | | |
396 | +-------------------------+------------+-----+-----+-----+
397 | || Max Number | 16 | Y | Y | N |
398 | || of VLAN | | | | |
400 | || physical | | | | |
403 +------------+-------------------------+------------+-----+-----+-----+
404 || Reception | Rx_on_time | Supported | Y | Y | N |
405 || Window | | | | | |
406 || Monitoring| | | | | |
407 || (Counters)| | | | | |
408 | +-------------------------+------------+-----+-----+-----+
409 | | Rx_early | Supported | N | N | N |
410 | +-------------------------+------------+-----+-----+-----+
411 | | Rx_late | Supported | N | N | N |
412 | +-------------------------+------------+-----+-----+-----+
413 | | Rx_corrupt | Supported | N | N | N |
414 | +-------------------------+------------+-----+-----+-----+
415 | || Rx_pkt_dupl | Supported | N | N | N |
416 | +-------------------------+------------+-----+-----+-----+
417 | || Total_msgs_rcvd | Supported | Y | N | N |
419 +------------+-------------------------+------------+-----+-----+-----+
420 || || RU || Index and | Y | Y | N |
421 || Beam-\ || beamforming || weights | | | |
422 || forming || type || | | | |
423 | +-------------------------+------------+-----+-----+-----+
424 | || Beamforming | C-plane | Y | N | N |
425 | || control | | | | |
426 | || method | | | | |
427 | +-------------------------+------------+-----+-----+-----+
428 | || Number of || No res- | Y | Y | N |
429 | || beams || strictions| | | |
431 +------------+-------------------------+------------+-----+-----+-----+
432 || IQ || U-plane | Supported | Y | Y | Y |
433 || compre || data | | | | |
434 | ssion || compression | | | | |
435 | || method | | | | |
436 | +-------------------------+------------+-----+-----+-----+
437 | || U-plane || BFP: | Y | Y | Y |
438 | || data IQ || 8,9,12,14 | | | |
439 | || bitwidth || bits | | | |
440 | || (Before / || | | | |
441 | || After || | | | |
442 | || compression) || | | | |
443 | +-------------------------+------------+-----+-----+-----+
444 | || Static | Supported | N | N | N |
445 | || configuration | | | | |
446 | || of U-plane | | | | |
447 | || IQ format | | | | |
449 | || compression | | | | |
450 | || header | | | | |
452 +------------+-------------------------+------------+-----+-----+-----+
453 || eCPRI || ecpriVersion | 001b | Y | Y | Y |
454 || Header || | | | | |
455 || Format || | | | | |
456 | +-------------------------+------------+-----+-----+-----+
457 | || ecpriReserved | Supported | Y | Y | Y |
458 | +-------------------------+------------+-----+-----+-----+
459 | || ecpriCon || Not | N | N | N |
460 | | catenation || supported | | | |
461 | +------------+------------+------------+-----+-----+-----+
462 | || ecpri\ | U-plane | Supported | Y | Y | Y |
463 | || Message | | | | | |
464 | | +------------+------------+-----+-----+-----+
465 | | | C-plane | Supported | Y | Y | Y |
466 | | +------------+------------+-----+-----+-----+
467 | | || Delay | Supported | Y | Y | Y |
468 | | || measure | | | | |
470 | +------------+------------+------------+-----+-----+-----+
471 | || ecpri\ | Supported | Y | Y | Y |
472 | || Payload | | | | |
473 | || (payload | | | | |
474 | || size in | | | | |
475 | || bytes) | | | | |
476 | +-------------------------+------------+-----+-----+-----+
477 | || ecpriRtcid | Supported | Y | Y | Y |
478 | || /ecpriPcid | | | | |
479 | +-------------------------+------------+-----+-----+-----+
480 | || ecpri | Supported | Y | Y | Y |
481 | || Seqid: | | | | |
482 | || Sequence | | | | |
484 | +-------------------------+------------+-----+-----+-----+
485 | || ecpri\ | Supported | Y | Y | Y |
486 | || Seqid: | | | | |
488 | +-------------------------+------------+-----+-----+-----+
489 | || ecpri\ || Not | N | N | N |
490 | || Seqid: || supported | | | |
492 | || sequence | | | | |
495 +------------+------------+------------+------------+-----+-----+-----+
496 || C-plane || Section || Not | N | N | N |
497 || Type || Type 0 || supported | | | |
498 | +-------------------------+------------+-----+-----+-----+
499 | || Section | Supported | Y | Y | Y |
500 | || Type 1 | | | | |
501 | +-------------------------+------------+-----+-----+-----+
502 | || Section | Supported | Y | Y | Y |
503 | || Type 3 | | | | |
504 | +-------------------------+------------+-----+-----+-----+
505 | || Section || Not | N | N | N |
506 | || Type 5 || supported | | | |
507 | +-------------------------+------------+-----+-----+-----+
508 | || Section || Not | N | N | N |
509 | || Type 6 || supported | | | |
510 | +-------------------------+------------+-----+-----+-----+
511 | || Section || Not | N | N | N |
512 | || Type 7 || supported | | | |
514 +------------+------------+------------+------------+-----+-----+-----+
515 || C-plane || *Coding*\ || data\ | Supported | Y | Y | N |
516 || Packet || *of Infor*|| Direction | | | | |
517 || Format | *mation* || (data | | | | |
518 | || *Elements*|| direction | | | | |
519 | || *Appli* || (gNB | | | | |
520 | | *cation* || Tx/Rx)) | | | | |
521 | || *Layer,*\ || | | | | |
522 | || *Common* || | | | | |
523 | | +------------+------------+-----+-----+-----+
524 | | || payload || 001b | Y | Y | N |
525 | | | Version || | | | |
526 | | || (payload || | | | |
527 | | || version) || | | | |
528 | | +------------+------------+-----+-----+-----+
529 | | || filter | Supported | Y | Y | N |
530 | | | Index | | | | |
531 | | || (filter | | | | |
532 | | || index) | | | | |
533 | | +------------+------------+-----+-----+-----+
534 | | || frameId | Supported | Y | Y | N |
535 | | || (frame | | | | |
536 | | || iden | | | | |
537 | | | tifier) | | | | |
538 | | +------------+------------+-----+-----+-----+
539 | | || subframeId| Supported | Y | Y | N |
540 | | || (subframe | | | | |
541 | | || iden | | | | |
542 | | | tifier) | | | | |
543 | | +------------+------------+-----+-----+-----+
544 | | || slotId | Supported | Y | Y | N |
545 | | || (slot | | | | |
546 | | || iden | | | | |
547 | | | tifier) | | | | |
548 | | +------------+------------+-----+-----+-----+
549 | | || start\ | Supported | Y | Y | N |
550 | | || Symbolid | | | | |
551 | | || (start | | | | |
552 | | || symbol | | | | |
553 | | || iden | | | | |
554 | | | tifier) | | | | |
555 | | +------------+------------+-----+-----+-----+
556 | | || number || up to the | Y | Y | N |
557 | | || Ofsections|| maximum | | | |
558 | | || (number of|| number of | | | |
559 | | || sections) || PRBs | | | |
560 | | +------------+------------+-----+-----+-----+
561 | | || section\ || 1 and 3 | Y | Y | N |
562 | | || Type || | | | |
563 | | || (section || | | | |
564 | | || type) || | | | |
565 | | +------------+------------+-----+-----+-----+
566 | | || udCompHdr | Supported | Y | Y | N |
567 | | || (user data| | | | |
569 | | | pression | | | | |
570 | | || header) | | | | |
571 | | +------------+------------+-----+-----+-----+
572 | | || number\ || Not | N | N | N |
573 | | || OfUEs || supported | | | |
574 | | || (number Of| | | | |
575 | | || UEs) | | | | |
576 | | +------------+------------+-----+-----+-----+
577 | | || timeOffset| Supported | Y | Y | N |
578 | | || (time | | | | |
579 | | || offset) | | | | |
580 | | +------------+------------+-----+-----+-----+
581 | | || frame\ | mu=0,1,3 | Y | Y | N |
582 | | || Structure | | | | |
583 | | || (frame | | | | |
584 | | || structure)| | | | |
585 | | +------------+------------+-----+-----+-----+
586 | | || cpLength | Supported | Y | Y | N |
587 | | || (cyclic | | | | |
588 | | || prefix | | | | |
589 | | || length) | | | | |
590 | +------------+------------+------------+-----+-----+-----+
591 | || *Coding* || sectionId | Supported | Y | Y | N |
592 | || *of Infor*|| (section | | | | |
593 | | *mation* || iden | | | | |
594 | || *Elements*| tifier) | | | | |
595 | || *Ap* | | | | | |
596 | | *plication*| | | | | |
597 | || *Layer,* | | | | | |
598 | || *Sections*| | | | | |
599 | | +------------+------------+-----+-----+-----+
600 | | || rb | 0 | Y | Y | N |
601 | | || (resource | | | | |
602 | | || block | | | | |
603 | | || indicator)| | | | |
604 | | +------------+------------+-----+-----+-----+
605 | | || symInc | 0 or 1 | Y | Y | N |
606 | | || (symbol | | | | |
607 | | || number | | | | |
608 | | || increment | | | | |
609 | | || command) | | | | |
610 | | +------------+------------+-----+-----+-----+
611 | | || startPrbc | Supported | Y | Y | N |
612 | | || (starting | | | | |
613 | | || PRB of | | | | |
614 | | || control | | | | |
615 | | || section) | | | | |
616 | | +------------+------------+-----+-----+-----+
617 | | || reMask | Supported | Y | Y | N |
618 | | || (resource | | | | |
619 | | || element | | | | |
620 | | || mask) | | | | |
621 | | +------------+------------+-----+-----+-----+
622 | | || numPrbc | Supported | Y | Y | N |
623 | | || (number of| | | | |
624 | | || contiguous| | | | |
625 | | || PRBs per | | | | |
626 | | || control | | | | |
627 | | || section) | | | | |
628 | | +------------+------------+-----+-----+-----+
629 | | || numSymbol | Supported | Y | Y | N |
630 | | || (number of| | | | |
631 | | || symbols) | | | | |
632 | | +------------+------------+-----+-----+-----+
633 | | || ef | Supported | Y | Y | N |
634 | | || (extension| | | | |
635 | | || flag) | | | | |
636 | | +------------+------------+-----+-----+-----+
637 | | || beamId | Support | Y | Y | N |
638 | | || (beam | | | | |
639 | | || iden | | | | |
640 | | | tifier) | | | | |
641 | | +------------+------------+-----+-----+-----+
642 | | || ueId (UE || Not | N | N | N |
643 | | || iden || supported | | | |
644 | | | tifier) | | | | |
645 | | +------------+------------+-----+-----+-----+
646 | | || freqOffset| Supported | Y | Y | N |
647 | | || (frequency| | | | |
648 | | || offset) | | | | |
649 | | +------------+------------+-----+-----+-----+
650 | | || regulari || Not | N | N | N |
651 | | | zation\ || supported | | | |
652 | | || Factor || | | | |
653 | | || (regulari | | | | |
654 | | | zation | | | | |
655 | | || Factor) | | | | |
656 | | +------------+------------+-----+-----+-----+
657 | | || ciIsample,|| Not | N | N | N |
658 | | || ciQsample || supported | | | |
659 | | || (channel || | | | |
660 | | || infor | | | | |
661 | | | mation | | | | |
662 | | || I and Q | | | | |
663 | | || values) | | | | |
664 | | +------------+------------+-----+-----+-----+
665 | | || laaMsgType|| Not | N | N | N |
666 | | || (LAA || supported | | | |
667 | | || message || | | | |
668 | | || type) || | | | |
669 | | +------------+------------+-----+-----+-----+
670 | | || laaMsgLen || Not | N | N | N |
671 | | || (LAA || supported | | | |
672 | | || message | | | | |
673 | | || length) | | | | |
674 | | +------------+------------+-----+-----+-----+
675 | | | lbtHandle || Not | N | N | N |
676 | | | || supported | | | |
677 | | +------------+------------+-----+-----+-----+
678 | | || lbtDefer || Not | N | N | N |
679 | | || Factor || supported | | | |
680 | | || (listen || | | | |
681 | | || before || | | | |
682 | | || talk || | | | |
683 | | || defer || | | | |
684 | | || factor) || | | | |
685 | | +------------+------------+-----+-----+-----+
686 | | || lbtBack || Not | N | N | N |
687 | | || offCounter|| supported | | | |
688 | | || (listen || | | | |
689 | | || before || | | | |
690 | | || talk || | | | |
691 | | || backoff || | | | |
692 | | || counter) || | | | |
693 | | +------------+------------+-----+-----+-----+
694 | | || lbtOffset || Not | N | N | N |
695 | | || (listen- || supported | | | |
696 | | || before | | | | |
697 | | || talk || | | | |
698 | | || offset) | | | | |
699 | | +------------+------------+-----+-----+-----+
700 | | || MCOT || Not | N | N | N |
701 | | || (maximum || supported | | | |
702 | | || channel | | | | |
703 | | || occupancy | | | | |
704 | | || time) | | | | |
705 | | +------------+------------+-----+-----+-----+
706 | | || lbtMode || Not | N | N | N |
707 | | || (LBT Mode)|| supported | | | |
708 | | +------------+------------+-----+-----+-----+
709 | | || lbt || Not | N | N | N |
710 | | | PdschRes || supported | | | |
711 | | || (LBT PDSCH|| | | | |
712 | | || Result) | | | | |
713 | | +------------+------------+-----+-----+-----+
714 | | || sfStatus || Not | N | N | N |
715 | | || (subframe || supported | | | |
716 | | || status) || | | | |
717 | | +------------+------------+-----+-----+-----+
718 | | || lbtDrsRes || Not | N | N | N |
719 | | || (LBT DRS || supported | | | |
720 | | || Result) | | | | |
721 | | +------------+------------+-----+-----+-----+
722 | | || initial || Not | N | N | N |
723 | | | PartialSF || supported | | | |
724 | | || (Initial | | | | |
725 | | | partial | | | | |
727 | | +------------+------------+-----+-----+-----+
728 | | || lbtBufErr || Not | N | N | N |
729 | | || (LBT || supported | | | |
730 | | | Buffer | | | | |
731 | | || Error) | | | | |
732 | | +------------+------------+-----+-----+-----+
733 | | || sfnSf || Not | N | N | N |
734 | | || (SFN/SF || supported | | | |
736 | | +------------+------------+-----+-----+-----+
737 | | || lbt || Not | N | N | N |
738 | | || CWConfig_H|| supported | | | |
739 | | || (HARQ | | | | |
740 | | || Parameters| | | | |
742 | | || Congestion| | | | |
743 | | || Window | | | | |
744 | | || mana | | | | |
745 | | | gement) | | | | |
746 | | +------------+------------+-----+-----+-----+
747 | | || lbt || Not | N | N | N |
748 | | || CWConfig_T|| supported | | | |
750 | | | Parameters | | | | |
752 | | || Congestion| | | | |
753 | | || Window | | | | |
754 | | || mana | | | | |
755 | | | gement) | | | | |
756 | | +------------+------------+-----+-----+-----+
757 | | || lbtTr || Not | N | N | N |
758 | | | afficClass || supported | | | |
759 | | || (Traffic | | | | |
760 | | || class | | | | |
761 | | || priority | | | | |
763 | | || Congestion| | | | |
764 | | || Window | | | | |
765 | | || mana | | | | |
766 | | | gement) | | | | |
767 | | +------------+------------+-----+-----+-----+
768 | | || lbtCWR_Rst|| Not | N | N | N |
769 | | || (Noti || supported | | | |
770 | | | cation | | | | |
771 | | || about | | | | |
772 | | || packet | | | | |
773 | | || reception | | | | |
774 | | || successful| | | | |
775 | | || or not) | | | | |
776 | | +------------+------------+-----+-----+-----+
777 | | || reserved | 0 | N | N | N |
778 | | || (reserved | | | | |
779 | | || for future| | | | |
780 | | || use) | | | | |
781 | | +------------+------------+-----+-----+-----+
782 | | || *Section* | | | | |
783 | | || *Exten* | | | | |
784 | | | *sion* | | | | |
785 | | || *Commands*| | | | |
786 | | +------------+------------+-----+-----+-----+
787 | | || extType | Supported | Y | Y | N |
788 | | || (extension| | | | |
789 | | || type) | | | | |
790 | | +------------+------------+-----+-----+-----+
791 | | || ef | Supported | Y | Y | N |
792 | | | (extension | | | | |
793 | | || flag) | | | | |
794 | | +------------+------------+-----+-----+-----+
795 | | || extLen | Supported | Y | Y | N |
796 | | || (extension| | | | |
797 | | || length) | | | | |
798 | +------------+------------+------------+-----+-----+-----+
799 | || Coding of | | | | | |
800 | || Infor | | | | | |
801 | | mation | | | | | |
802 | || Elements –| | | | | |
803 | || Appli | | | | | |
804 | | cation | | | | | |
805 | || Layer, | | | | | |
806 | || Section | | | | | |
807 | || Exten | | | | | |
808 | | sions | | | | | |
809 | +------------+------------+------------+-----+-----+-----+
811 | || *Ext*\ || bfw | Supported | Y | Y | N |
812 | || *Type=1:* || CompHdr | | | | |
813 | || *Beam* || (beam\ | | | | |
814 | || *forming* | forming | | | | |
815 | || *Weights* || weight | | | | |
816 | || *Exten\* || compre\ | | | | |
817 | | *sion* | ssion | | | | |
818 | || *Type* || header) | | | | |
819 | || +------------+------------+-----+-----+-----+
821 | || || bf | Supported | Y | Y | N |
822 | || | wCompParam | | | | |
823 | || || (beam | | | | |
824 | || || forming | | | | |
825 | || || weight | | | | |
826 | || || compre\ | | | | |
827 | || | ssion | | | | |
828 | || || parameter)| | | | |
829 | || +------------+------------+-----+-----+-----+
830 | || || bfwl | Supported | Y | Y | N |
831 | || || (beam | | | | |
832 | || | forming | | | | |
833 | || || weight | | | | |
834 | || || in-phase | | | | |
835 | || || value) | | | | |
836 | || +------------+------------+-----+-----+-----+
837 | || || bfwQ | Supported | Y | Y | N |
838 | || || (beam | | | | |
839 | || | forming | | | | |
840 | || || weight | | | | |
841 | || || quadrature| | | | |
842 | || || value) | | | | |
843 | +------------+------------+------------+-----+-----+-----+
844 | || || bfaCompHdr| Supported | Y | N | N |
845 | || *ExtType*\|| | | | | |
846 | || *=2:* || (beam\ | | | | |
847 | || *Beam* | forming | | | | |
848 | | *forming* || attributes| | | | |
849 | || *Attribu* || compre | | | | |
850 | | *tes* | ssion | | | | |
851 | || *Exten* || header) | | | | |
852 | || *sion* | | | | | |
853 | || *Type* | | | | | |
854 | || +------------+------------+-----+-----+-----+
855 | || || bfAzPt | Supported | Y | N | N |
856 | || || (beam | | | | |
857 | || | forming | | | | |
858 | || || azimuth | | | | |
859 | || || pointing | | | | |
860 | || || parameter)| | | | |
861 | || +------------+------------+-----+-----+-----+
862 | || || bfZePt | Supported | Y | N | N |
863 | || || (beam | | | | |
864 | || | forming | | | | |
865 | || || zenith | | | | |
866 | || || pointing | | | | |
867 | || || parameter)| | | | |
868 | || +------------+------------+-----+-----+-----+
869 | || || bfAz3dd | Supported | Y | N | N |
870 | || || (beam | | | | |
871 | || | forming | | | | |
872 | || || azimuth | | | | |
873 | || || beamwidth | | | | |
874 | || || parameter)| | | | |
875 | || +------------+------------+-----+-----+-----+
876 | || || bfZe3dd | Supported | Y | N | N |
877 | || || (beam | | | | |
878 | || | forming | | | | |
879 | || || zenith | | | | |
880 | || || beamwidth | | | | |
881 | || || parameter)| | | | |
882 | || +------------+------------+-----+-----+-----+
883 | || || bfAzSl | Supported | Y | N | N |
884 | || || (beam | | | | |
885 | || | forming | | | | |
886 | || || azimuth | | | | |
887 | || || sidelobe | | | | |
888 | || || parameter)| | | | |
889 | || +------------+------------+-----+-----+-----+
890 | || || bfZeSl | Supported | Y | N | N |
891 | || || (beam | | | | |
892 | || | forming | | | | |
893 | || || zenith | | | | |
894 | || || sidelobe | | | | |
895 | || || parameter)| | | | |
896 | || +------------+------------+-----+-----+-----+
897 | || || zero- | Supported | Y | N | N |
898 | || | padding | | | | |
899 | +------------+------------+------------+-----+-----+-----+
900 | || || code\ | Supported | Y | N | N |
901 | || *ExtType* || bookIndex | | | | |
902 | || *=3:* || | | | | |
903 | || *DL* || (precoder | | | | |
904 | || *Preco* || codebook | | | | |
905 | | *ding* || | | | | |
906 | || *Exten* || used for | | | | |
907 | | *sion* || trans | | | | |
908 | || *Type* | mission | | | | |
910 | || +------------+------------+-----+-----+-----+
911 | || || layerID | Supported | Y | N | N |
912 | || || (Layer ID | | | | |
913 | || || for DL | | | | |
914 | || || trans | | | | |
915 | || | mission) | | | | |
916 | || +------------+------------+-----+-----+-----+
917 | || || txScheme | Supported | Y | N | N |
918 | || || (trans | | | | |
919 | || | mission | | | | |
920 | || || scheme) | | | | |
921 | || +------------+------------+-----+-----+-----+
922 | || || numLayers | Supported | Y | N | N |
923 | || || (number of| | | | |
924 | || || layers | | | | |
925 | || || used for | | | | |
927 | || || trans | | | | |
928 | || | mission) | | | | |
929 | || +------------+------------+-----+-----+-----+
930 | || || crsReMask | Supported | Y | N | N |
931 | || || (CRS | | | | |
932 | || || resource | | | | |
933 | || || element | | | | |
934 | || || mask) | | | | |
935 | || +------------+------------+-----+-----+-----+
936 | | || crs\ | Supported | Y | N | N |
937 | | || SyumINum | | | | |
938 | | || (CRS | | | | |
939 | | || symbol | | | | |
940 | | || number | | | | |
941 | | || indi | | | | |
942 | | | cation) | | | | |
943 | | +------------+------------+-----+-----+-----+
944 | | || crsShift | Supported | Y | N | N |
945 | | || (crsShift | | | | |
946 | | || used for | | | | |
948 | | || trans | | | | |
949 | | | mission) | | | | |
950 | | +------------+------------+-----+-----+-----+
951 | | || beamIdAP1 | Supported | Y | N | N |
952 | | || (beam id | | | | |
953 | | || to be used| | | | |
955 | | || antenna | | | | |
956 | | || port 1) | | | | |
957 | | +------------+------------+-----+-----+-----+
958 | | || beamIdAP2 | Supported | Y | N | N |
959 | | || (beam id | | | | |
960 | | || to be used| | | | |
962 | | || antenna | | | | |
963 | | || port 2) | | | | |
964 | | +------------+------------+-----+-----+-----+
965 | | || beamIdAP3 | Supported | Y | N | N |
966 | | || (beam id | | | | |
967 | | || to be used| | | | |
969 | | || antenna | | | | |
970 | | || port 3) | | | | |
972 | +------------+------------+------------+-----+-----+-----+
973 | | || csf || Supported | Y | Y | N |
974 | || *ExtType*\|| (cons || | | | |
975 | || *=4:* | tellation || | | | |
976 | || *Modula* || shift | | | | |
977 | | *tion* || flag) | | | | |
978 | || *Compre* || | | | | |
979 | | *ssion* || | | | | |
980 | || *Parame* || | | | | |
981 | | *ters* || | | | | |
982 | || *Exten* || | | | | |
983 | | *sion* | | | | | |
984 | || *Type* || | | | | |
985 | | +------------+------------+-----+-----+-----+
986 | | || mod || Supported | Y | Y | N |
987 | | || CompScaler|| | | | |
989 | | || modulation|| | | | |
990 | | || compre || | | | |
991 | | | ssion || | | | |
992 | | || scaler || | | | |
993 | | | value) || | | | |
994 | +------------+------------+------------+-----+-----+-----+
995 | || || mcScale\ || Supported | Y | N | N |
996 | || *ExtType*\|| ReMask || | | | |
997 | || *=5:* || ( || | | | |
998 | || *Modula* || modulation|| | | | |
999 | | *tion* || compre || | | | |
1000 | || *Compre* | ssion || | | | |
1001 | | *ssion* || power || | | | |
1002 | || *Additio* || RE || | | | |
1003 | || *Parame* || mask) || | | | |
1004 | || *ters* | || | | | |
1005 | || *Exten* || | | | | |
1006 | | *sion* || | | | | |
1007 | || Type* | || | | | |
1008 | | +------------+------------+-----+-----+-----+
1009 | | || csf || Supported | Y | N | N |
1010 | | || (cons || | | | |
1011 | | | tellation || | | | |
1012 | | || shift || | | | |
1013 | | || flag) || | | | |
1014 | | +------------+------------+-----+-----+-----+
1015 | | || mcScale\ | Supported | Y | N | N |
1016 | | || Offset | | | | |
1017 | | || (scaling | | | | |
1018 | | || value for | | | | |
1019 | | || modulation| | | | |
1020 | | || compre | | | | |
1021 | | | ssion) | | | | |
1022 | +------------+------------+------------+-----+-----+-----+
1023 | || *E* || rbgSize | Supported | Y | N | N |
1024 | | *xtType=6:*|| (resource | | | | |
1025 | || *Non-con* || block | | | | |
1026 | | *tiguous* || group | | | | |
1027 | || *PRB* || size) | | | | |
1028 | || *alloca* | | | | | |
1029 | | *tion in* | | | | | |
1030 | || *time and*| | | | | |
1031 | || *frequen* | | | | | |
1032 | | *cy domain*| | | | | |
1033 | | +------------+------------+-----+-----+-----+
1034 | | || rbgMask | Supported | Y | N | N |
1035 | | || (resource | | | | |
1036 | | || block | | | | |
1037 | | || group bit | | | | |
1038 | | || mask) | | | | |
1039 | | +------------+------------+-----+-----+-----+
1040 | | || symbol\ | Supported | Y | N | N |
1041 | | || Mask | | | | |
1042 | | || (symbol | | | | |
1043 | | || bit mask) | | | | |
1044 | +------------+------------+------------+-----+-----+-----+
1045 | || *Ext* || beam | Supported | Y | N | N |
1046 | | *Type=10:* || GroupType | | | | |
1047 | || *Section* | | | | | |
1048 | || *des\* | | | | | |
1049 | | *cription* | | | | | |
1050 | || *for gro\*| | | | | |
1051 | | *up* | | | | | |
1052 | || *configu\*| | | | | |
1053 | | *ration of*| | | | | |
1054 | || *multiple*| | | | | |
1055 | || *ports* | | | | | |
1057 | | +------------+------------+-----+-----+-----+
1058 | | | numPortc | Supported | Y | N | N |
1060 | +------------+------------+------------+-----+-----+-----+
1061 | || *Ext* || b | Supported | Y | Y | N |
1062 | | *Type=11:* | fwCompHdr | | | | |
1063 | || *Flexible*|| (beam | | | | |
1064 | || *Beam* | forming | | | | |
1065 | | *forming* || weight | | | | |
1066 | || *Weights* || compre | | | | |
1067 | || *Exten* | ssion | | | | |
1068 | | *sion* | | | | | |
1069 | || *Type* || header) | | | | |
1070 | | +------------+------------+-----+-----+-----+
1071 | | || bfw | Supported | Y | Y | N |
1072 | | || CompParam | | | | |
1073 | | || for PRB | | | | |
1074 | | || bundle x | | | | |
1075 | | || (beam | | | | |
1076 | | | forming | | | | |
1077 | | || weight | | | | |
1078 | | || compre | | | | |
1079 | | | ssion | | | | |
1080 | | || parameter)| | | | |
1081 | | +------------+------------+-----+-----+-----+
1082 | | || numBund\ | Supported | Y | Y | N |
1084 | | || (Number | | | | |
1086 | | || bundled | | | | |
1087 | | || PRBs per | | | | |
1088 | | || beam | | | | |
1089 | | | forming | | | | |
1090 | | || weights) | | | | |
1091 | | +------------+------------+-----+-----+-----+
1092 | | || bfwI | Supported | Y | Y | N |
1093 | | || (beam | | | | |
1094 | | | forming | | | | |
1095 | | || weight | | | | |
1096 | | || in-phase | | | | |
1097 | | || value) | | | | |
1098 | | +------------+------------+-----+-----+-----+
1099 | | || bfwQ | Supported | Y | Y | N |
1100 | | || (beam | | | | |
1101 | | | forming | | | | |
1102 | | || weight | | | | |
1103 | | || quadra | | | | |
1104 | | | ture | | | | |
1105 | | || value) | | | | |
1106 | | +------------+------------+-----+-----+-----+
1107 | | || disable\ | Supported | Y | Y | N |
1108 | | || BFWs | | | | |
1109 | | || (disable | | | | |
1110 | | || beam | | | | |
1111 | | | forming | | | | |
1112 | | || weights) | | | | |
1113 | | +------------+------------+-----+-----+-----+
1114 | | || RAD | Supported | Y | Y | N |
1115 | | || (Reset | | | | |
1116 | | || After PRB | | | | |
1117 | | || Discon | | | | |
1118 | | | tinuity) | | | | |
1120 +------------+------------+------------+------------+-----+-----+-----+
1121 || U-plane || data\ | Supported | Y | Y | Y |
1122 || Packet || Direction | | | | |
1123 || Format || (data | | | | |
1124 | || direction | | | | |
1126 | || Tx/Rx)) | | | | |
1127 | +-------------------------+------------+-----+-----+-----+
1128 | || payload\ | 001b | Y | Y | Y |
1129 | || Version | | | | |
1130 | || (payload | | | | |
1131 | || version) | | | | |
1132 | +-------------------------+------------+-----+-----+-----+
1133 | || filter\ | Supported | Y | Y | Y |
1134 | || Index | | | | |
1135 | || (filter | | | | |
1136 | || index) | | | | |
1137 | +-------------------------+------------+-----+-----+-----+
1138 | || frameId | Supported | Y | Y | Y |
1139 | || (frame | | | | |
1141 | | tifier) | | | | |
1142 | +-------------------------+------------+-----+-----+-----+
1143 | || subframeId | Supported | Y | Y | Y |
1144 | || (subframe | | | | |
1146 | | tifier) | | | | |
1147 | +-------------------------+------------+-----+-----+-----+
1148 | || slotId | Supported | Y | Y | Y |
1149 | || (slot | | | | |
1151 | | tifier) | | | | |
1152 | +-------------------------+------------+-----+-----+-----+
1153 | || symbolId | Supported | Y | Y | Y |
1154 | || (symbol | | | | |
1156 | | tifier) | | | | |
1157 | +-------------------------+------------+-----+-----+-----+
1158 | || sectionId | Supported | Y | Y | Y |
1159 | || (section | | | | |
1161 | | tifier) | | | | |
1162 | +-------------------------+------------+-----+-----+-----+
1163 | || rb | 0 | Y | Y | Y |
1164 | || (resource | | | | |
1165 | || block | | | | |
1166 | || indicator) | | | | |
1167 | +-------------------------+------------+-----+-----+-----+
1168 | || symInc | 0 | Y | Y | Y |
1169 | || (symbol | | | | |
1170 | || number | | | | |
1171 | || increment | | | | |
1172 | || command) | | | | |
1173 | +-------------------------+------------+-----+-----+-----+
1174 | || startPrbu | Supported | Y | Y | Y |
1175 | || (startingPRB | | | | |
1176 | || of user | | | | |
1177 | || plane | | | | |
1178 | || section) | | | | |
1179 | +-------------------------+------------+-----+-----+-----+
1180 | || numPrbu | Supported | Y | Y | Y |
1181 | || (number of | | | | |
1182 | || PRBs per | | | | |
1183 | || user plane | | | | |
1184 | || section) | | | | |
1185 | +-------------------------+------------+-----+-----+-----+
1186 | || udCompHdr | Supported | Y | Y | N |
1187 | || (user data | | | | |
1189 | | pression | | | | |
1190 | || header) | | | | |
1191 | +-------------------------+------------+-----+-----+-----+
1192 | || reserved | 0 | Y | Y | Y |
1193 | || (reserved | | | | |
1194 | || for future | | | | |
1196 | +-------------------------+------------+-----+-----+-----+
1197 | || udCompParam | Supported | Y | Y | N |
1198 | || (user data | | | | |
1199 | || compre | | | | |
1201 | || parameter) | | | | |
1202 | +-------------------------+------------+-----+-----+-----+
1203 | || iSample | 16 | Y | Y | Y |
1204 | || (in-phase | | | | |
1205 | | sample) | | | | |
1206 | +-------------------------+------------+-----+-----+-----+
1207 | || qSample | 16 | Y | Y | Y |
1209 | | quadrature | | | | |
1210 | | sample) | | | | |
1212 +------------+-------------------------+------------+-----+-----+-----+
1213 | S-plane || Topology | Supported | N | N | N |
1214 | || confi | | | | |
1215 | | guration: | | | | |
1217 | +-------------------------+------------+-----+-----+-----+
1218 | || Topology | Supported | N | N | N |
1219 | || confi | | | | |
1220 | | guration: | | | | |
1222 | +-------------------------+------------+-----+-----+-----+
1223 | || Topology | Supported | Y | Y | Y |
1224 | || confi | | | | |
1225 | | guration: | | | | |
1227 | +-------------------------+------------+-----+-----+-----+
1228 | || Topology | Supported | N | N | N |
1229 | || confi | | | | |
1230 | | guration: | | | | |
1233 + +------------+------------+------------+-----+-----+-----+
1234 | | PTP || Full | Supported | Y | Y | N |
1235 | | || Timing | | | | |
1236 | | || Support | | | | |
1237 | | || (G.8275.1)| | | | |
1239 +------------+------------+------------+------------+-----+-----+-----+
1240 | M-plane | | || Not | N | N | N |
1241 | | | || supported | | | |
1243 +------------+------------+------------+------------+-----+-----+-----+
1245 \* The bit width of each component in eAxC ID can be configurable.
1250 O-RAN Fronthaul data can be transported over Ethernet or IPv4/IPv6. In
1251 the current implementation, the O-RAN library supports only Ethernet with
1254 .. image:: images/Native-Ethernet-Frame-with-VLAN.jpg
1256 :alt: Figure 11. Native Ethernet Frame with VLAN
1258 Figure 11. Native Ethernet Frame with VLAN
1261 Standard DPDK routines are used to perform Transport Layer
1264 VLAN tag functionality is offloaded to NIC as per the configuration of
1265 VF (refer to Setup Configuration).
1267 The transport header is defined in the ORAN Fronthaul specification
1268 based on the eCPRI specification.
1270 .. image:: images/eCPRI-Header-Field-Definitions.jpg
1272 :alt: Figure 12. eCPRI Header Field Definitions
1274 Figure 12. eCPRI Header Field Definitions
1276 Only ECPRI_IQ_DATA = 0x00 and ECPRI_RT_CONTROL_DATA= 0x02 message types
1279 For one-way delay measurements the eCPRI Header Field Definitions are
1280 the same as above until the ecpriPayload. The one-delay measurement
1281 message format is shown in the next figure.
1283 .. image:: images/ecpri-one-way-delay-measurement-message.jpg
1285 :alt: Figure 13. ecpri one-way delay measurement message
1287 Figure 13. ecpri one-way delay measurement message
1289 In addition, for the eCPRI one-delay measurement message there is a
1290 requirement of dummy bytes insertion so the overall ethernet frame has
1293 The measurement ID is a one-byte value used by the sender of the request
1294 to distinguish the response received between different measurements.
1296 The action type is a one-byte value defined in Table 8 of the eCPRI
1299 Action Type 0x00 corresponds to a Request
1301 Action Type 0x01 corresponds to a Request with Follow Up
1303 Both values are used by an eCPRI node to initiate a one-way delay
1304 measurement in the direction of its own node to another node.
1306 Action Type 0x02 corresponds to a Response
1308 Action Type 0x03 is a Remote Request
1310 Action Type 0x04 is a Remote Request with Follow Up
1312 Values 0x03 and 0x04 are used when an eCPRI node needs to know the
1313 one-way delay from another node to itself.
1315 Action Type 0x05 is the Follow_Up message.
1317 The timestamp uses the IEEE-1588 Timestamp format with 8 bytes for the
1318 seconds part and 4 bytes for the nanoseconds part. The timestamp is a
1319 positive time with respect to the epoch.
1321 The compensation value is used with Action Types 0x00 (Request), 0x02
1322 (Response) or 0x05 (Follow_up) for all others this field contains zeros.
1323 This value is the compensation time measured in nanoseconds and
1324 multiplied by 2\ :sup:`16` and follows the format for the
1325 correctionField in the common message header specified by the IEE
1326 1588-2008 clause 13.3.
1328 Handling of ecpriRtcid/ecpriPcid Bit field size is configurable and can
1329 be defined on the initialization stage of the O-RAN library.
1331 .. image:: images/Bit-Allocations-of-ecpriRtcid-ecpriPcid.jpg
1333 :alt: Figure 14. Bit Allocations of ecpriRtcid/ecpriPcid
1335 Figure 14. Bit Allocations of ecpriRtcid/ecpriPcid
1337 For ecpriSeqid only, the support for a sequence number is implemented.
1338 The subsequent number is not supported.
1343 The following diagrams show O-RAN packet protocols’ headers and data
1344 arrangement with and without compression support.
1346 O-RAN packet meant for traffic with compression enabled has the
1347 Compression Header added after each Application Header. According to
1348 O-RAN Fronthaul's specification, the Compression Header is part of a
1349 repeated Section Application Header. In the O-RAN library implementation,
1350 the header is implemented as a separate structure, following the
1351 Application Section Header. As a result, the Compression Header is not
1352 included in the O-RAN packet, if compression is not used.
1354 Figure 15 shows the components of an ORAN packet.
1356 .. image:: images/xRAN-Packet-Components.jpg
1358 :alt: Figure 15. O-RAN Packet Components
1360 Figure 15. O-RAN Packet Components
1362 Radio Application Header
1363 ~~~~~~~~~~~~~~~~~~~~~~~~
1365 The next header is a common header used for time reference.
1367 .. image:: images/Radio-Application-Header.jpg
1369 :alt: Figure 16. Radio Application Header
1371 Figure 16. Radio Application Header
1373 The radio application header specific field values are implemented as
1380 - subframeId = [0:9]
1386 Data Section Application Data Header
1387 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1389 The Common Radio Application Header is followed by the Application
1390 Header that is repeated for each Data Section within the eCPRI message.
1391 The relevant section of O-RAN packet is shown in color.
1393 .. image:: images/Data-Section-Application-Data-Header.jpg
1395 :alt: Figure 17. Data Section Application Data Header
1397 Figure 17. Data Section Application Data Header
1400 A single section is used per one Ethernet packet with IQ samples
1401 startPrbu is equal to 0 and numPrbu is wqual to the number of RBs used:
1403 - rb field is not used (value 0).
1405 - symInc is not used (value 0)
1410 An O-RAN packet data payload contains a number of PRBs. Each PRB is built
1411 of 12 IQ samples. Flexible IQ bit width is supported. If compression is enabled udCompParam is included in the data payload. The data section is shown in colour.
1413 .. image:: images/Data-Payload.jpg
1415 :alt: Figure 17. Data Payload
1417 Figure 17. Data Payload
1422 C-Plane messages are encapsulated using a two-layered header approach.
1423 The first layer consists of an eCPRI standard header, including
1424 corresponding fields used to indicate the message type, while the second
1425 layer is an application layer including necessary fields for control and
1426 synchronization. Within the application layer, a “section” defines the characteristics of U-plane data to be transferred or received from a
1427 beam with one pattern id. In general, the transport header,application
1428 header, and sections are all intended to be aligned on 4-byte boundaries
1429 and are transmitted in “network byte order” meaning the most significant
1430 byte of a multi-byte parameter is transmitted first.
1432 Table 9 is a list of sections currently supported.
1434 Table 9. Section Types
1436 +--------------+--------------------------+--------------------------+
1437 | Section Type | Target Scenario | Remarks |
1438 +--------------+--------------------------+--------------------------+
1439 | 0 || Unused Resource Blocks | Not supported |
1440 | || or symbols in Downlink | |
1442 +--------------+--------------------------+--------------------------+
1443 | 1 || Most DL/UL radio | Supported |
1445 +--------------+--------------------------+--------------------------+
1446 | 2 | reserved for future use | N/A |
1447 +--------------+--------------------------+--------------------------+
1448 | 3 || PRACH and || Only PRACH is supported.|
1449 | || mixed-numerology || Mixed numerology is not |
1450 | || channels || supported. |
1451 +--------------+--------------------------+--------------------------+
1452 | 4 | Reserved for future use | Not supported |
1453 +--------------+--------------------------+--------------------------+
1454 | 5 || UE scheduling | Not supported |
1455 | || information (UE-ID | |
1456 | || assignment to section) | |
1457 +--------------+--------------------------+--------------------------+
1458 | 6 | Channel information | Not supported |
1459 +--------------+--------------------------+--------------------------+
1460 | 7 | LAA | Not supported |
1461 +--------------+--------------------------+--------------------------+
1462 | 8-255 | Reserved for future use | N/A |
1463 +--------------+--------------------------+--------------------------+
1465 Section extensions are not supported in this release.
1467 The definition of the C-Plane packet can be found lib/api/xran_pkt_cp.h
1468 and the fields are appropriately re-ordered in order to apply the
1469 conversion of network byte order after setting values.
1470 The comments in source code of O-RAN lib can be used to see more information on
1471 implementation specifics of handling sections as well as particular fields.
1472 Additional changes may be needed on C-plane to perform IOT with O-RU depending on the scenario.
1484 This header is defined as the structure of xran_ecpri_hdr in
1487 Radio Application Common Header
1488 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1490 The Radio Application Common Header is used for time reference. Its
1491 structure is shown in Figure 18.
1493 .. image:: images/Radio-Application-Common-Header.jpg
1495 :alt: Figure 19. Radio Application Common Header
1497 Figure 19. Radio Application Common Header
1499 This header is defined as the structure of
1500 xran_cp_radioapp_common_header in lib/api/xran_pkt_cp.h.
1502 Please note that the payload version in this header is fixed to
1503 XRAN_PAYLOAD_VER (defined as 1) in this release.
1505 Section Type 0 Structure
1506 ~~~~~~~~~~~~~~~~~~~~~~~~
1508 Figure 20 describes the structure of Section Type 0.
1510 .. image:: images/Section-Type-0-Structure.jpg
1512 :alt: Figure 20. Section Type 0 Structure
1514 Figure 20. Section Type 0 Structure
1516 In Figure 19 through Figure 23, the color yellow means it is a transport
1517 header; the color pink is the radio application header; others are
1520 Section Type 1 Structure
1521 ~~~~~~~~~~~~~~~~~~~~~~~~
1523 Figure 21 describes the structure of Section Type 1.
1525 .. image:: images/Section-Type-1-Structure.jpg
1527 :alt: Figure 21. Section Type 1 Structure
1529 Figure 21. Section Type 1 Structure
1531 Section Type 1 message has two additional parameters in addition to
1532 radio application common header:
1534 - udCompHdr : defined as the structure of xran_radioapp_udComp_header
1536 - reserved : fixed by zero
1538 Section type 1 is defined as the structure of xran_cp_radioapp_section1,
1539 and this part can be repeated to have multiple sections.
1541 Whole section type 1 message can be described in this summary:
1543 +----------------------------------+
1544 | xran_cp_radioapp_common_header |
1545 +==================================+
1546 | xran_cp_radioapp_section1_header |
1547 +----------------------------------+
1548 | xran_cp_radioapp_section1 |
1549 +----------------------------------+
1551 +----------------------------------+
1552 | xran_cp_radioapp_section1 |
1553 +----------------------------------+
1555 Section Type 3 Structure
1556 ~~~~~~~~~~~~~~~~~~~~~~~~
1558 Figure 22 describes the structure of Section Type 3.
1560 .. image:: images/Section-Type-3-Structure.jpg
1562 :alt: Figure 22. Section Type 3 Structure
1564 Figure 22. Section Type 3 Structure
1566 Section Type 3 message has below four additional parameters in addition
1567 to radio application common header.
1571 - frameStructure: defined as the structure of
1572 xran_cp_radioapp_frameStructure
1576 - udCompHdr: defined as the structure of xran_radioapp_udComp_header
1578 Section Type 3 is defined as the structure of xran_cp_radioapp_section3
1579 and this part can be repeated to have multiple sections.
1581 Whole section type 3 message can be described in this summary:
1583 +----------------------------------+
1584 | xran_cp_radioapp_common_header |
1585 +==================================+
1586 | xran_cp_radioapp_section3_header |
1587 +----------------------------------+
1588 | xran_cp_radioapp_section3 |
1589 +----------------------------------+
1591 +----------------------------------+
1592 | xran_cp_radioapp_section3 |
1593 +----------------------------------+
1595 Section Type 5 Structure
1596 ~~~~~~~~~~~~~~~~~~~~~~~~
1598 Figure 23 describes the structure of Section Type 5.
1600 .. image:: images/Section-Type-5-Structure.jpg
1602 :alt: Figure 23. Section Type 5 Structure
1604 Figure 23. Section Type 5 Structure
1607 Section Type 6 Structure
1608 ~~~~~~~~~~~~~~~~~~~~~~~~
1610 Figure 24 describes the structure of Section Type 6.
1612 .. image:: images/Section-Type-6-Structure.jpg
1614 :alt: Figure 24. Section Type 6 Structure
1616 Figure 24. Section Type 6 Structure