Minutes_EECT_031115_v2 - European Union Agency for Web viewThe modifications to the EIRENE SRS are...

Minutes of MeetingEECT #15 for the B3 next release


Lille, 03rd and 04th November2015

1. Adoption of the agenda and approval of the minutes of the meeting held on 06,07,08/10/2015

The agenda is adopted with the following amendment: on request by UNISIG and ERA three items are added in AOBs, see section 5.The minutes of the EECT meeting # 14 held on 06,07&08/10/15 are agreed with modifications, see revision marks in the file “Minutes_EECT_061015_v2revmarks.docx” distributed separately.

2. B3 next release – Triagea) Review of the list of open actions and pending assessments of CRs

Item not covered, due to lack of time

b) Assessment of new CR received


c) Project Plan


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3. Change Requests - Technical Resolution

CR HEADLINE DISCUSSION/DECISION

741 Packet data transmission for ETCS

EIRENE SRS:

The modifications to the EIRENE SRS are presented by UIC. The following items are discussed and clarified:

The domain “.etcs” shall only be used for ETCS entities. It is agreed to make a request for a public domain. The support of multiple PDP contexts and of multiplexed interface by the EDOR is considered as an M

requirement, not MI, as it would be an implementation issue. The time that the data communication is disrupted due to radio cell change is currently considered as M

only in the document. The specific values proposed are still under discussion. ERA/EUG remark that high values may impact the performance and that the concerned requirement could rather be classified as MI. U explains that, for the PS data, the upper protocol layers take anyway care of error correction/repetitions; and that disruption of around 1 second would be acceptable. The values suggested are within that range, therefore it is agreed to keep this requirement classified as M

A revision of the references included in the EIRENE document is suggested: in particular the documents from Annex A should not include version references, as these are the ones indicated in the TSI.

QoS defined for ETCS application is MI.

See tags “EECT041115” in the Word comments inside the embedded file below.

Regarding QoS, the profile is defined at the GSM-R network; the only thing that has to be requested is that it is “Streaming” for ETCS. The other parameters are predefined.

Action 15.01 U (ASAP): in the SUBSET-037, to specify a request of a QoS profile only regarding the traffic class

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(streaming) for ETCS.

SUBSET-037

Three batches of comments (against version 3.1.3 and 3.1.4) from individual railways have reached directly the ER WG, with no circulation prior to the meeting. The two batches against version 3.1.3 were pre-discussed within the ER WG while the one against version 3.1.4 has only been processed by the ER WG leader (Frank Kaiser). Some of the comments are discussed during the meeting, see tags EECT 151104 inside the embedded file below.

Regarding the discussion on TCP parameters: EUG requests to make as much as possible configurable all these parameters from trackside point of view, they consider that recommending values in the SUBSET-037 could be an interoperability problem if the solution does not work with such a recommendation. U clarifies that the values recommended are just for information and that what is mandatory is to be inside of the range of values defined in 8.3.3 Table 41. The ER WG intends to provide a document next year to justify their choice; currently they do not have human resources to draft it. EUG points out that the justifications should precede the decision and not the opposite. However ERA stresses that in the frame of the very tight B3R2 programme, the only pragmatic way forward is to trust that the values chosen by the ER WG will be future proof at least until the next release.

Action 15.01b U (13/11/15) : To provide an updated SUBSET-037 as per comments agreed during the meeting.

Action 15.02 U (June 16): To provide a paper justifying the values chosen for the TCP parameters

Review of action 14.07 (“To check if ETSI standard 27.010 has any fuzzy area that could hamper the ETCS on-board certification”)

U has prepared the necessary modifications to the SUBSET-037 chapter 6, in order to make mandatory the implementation of the ETSI 27.010 in the ETCS on-board. Concerning the DLC establishment services, it is agreed

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not to predefine priority levels for applications other than ETCS (which is given the highest one) because these shall be anyway managed by the EVC, the MT being the slave. See tag EECT 151104 inside the embedded file below, listing the modifications to the SUBSET-037 chapter 6.

1087 Manual Network Selection

No comment received from EUG on the ERA updated solution proposal (19/10/15). The review comments from U (23/10/15) are discussed. The CR is closed with the agreed modifications highlighted in blue in the file embedded below:

1255Impossibility to transmit unknown values in the

message “Additional data

The ERA updated solution proposal (19/10/15) was already agreed by U (23/10/15) and EUG (29/10/15) prior to the meeting and is therefore closed.

1237 KMS evolution Regarding the SUBSET-137:

The modifications implemented in SUBSET-137 0.3.0 are presented by U.

In particular, the section 7.2 is heavily questioned because it is not clear how an end-to-end connection could be established between the on-board and a Certificate Authority (CA) or a Registration Authority (RA), which can be anything like e.g. governmental organisations. It is therefore clarified that :

For Key Management, to access the Home KMC (and also CA and RA) will always be done via the Home GGSN. U indicates that the values mnc and mcc will be taken from the IMSI. This does not change anything

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on the communication side. the domain “.etcs” shall only be used for ETCS entities and KMC, not for the CA or the RA. the home network shall be responsible through its KMS DNS to resolve the FQDN of both the CA and RA. The QoS parameters for non-ETCS applications will be specified only in the EIRENE SRS and not in the

SUBSET-137. It has to be requested “as subscribed”, i.e. the EVC should not ask in the PDP context activation for specific values.

To take into account the above, the section 7.2 is reworked accordingly (see embedded file below) together with the necessity to modify the EIRENE SRS clauses 9.14.3 and 9.14.5 to reflect that.

Action 15.03 UIC (ASAP) to derive the modifications to the EIRENE SRS clauses 9.14.3 and 9.14.5, in order to deal with the establishment of OBU/CA&RA connections.

Another modification not resulting from the previous actions/decisions is also introduced by U, which consists of the suppression of “abort” message. This modification comes from a divergence between the KMS WG and the ER WG, which has been arbitrated by ERA and which was resolved just before the issuance of this version 0.3.0.

Post meeting note: the memo embedded below, drafted after the resolution of this issue, describes this latter and justifies the suppression of the “abort” message.

EUG mentions that, although posted on 28/10, they have not had the opportunity to look at this version 0.3.0 and they would like to perform a last quality check of the document. ERA replies that first the CR1237 will be closed

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without any further SUBSET-137 review round and that this quality check will be part of the B3R2 documentation quality check review after the implementation of the CRs into the concerned documents.

Regarding the SUBSET-037:

The necessary modifications induced by the CR1237 have been implemented by U in the SUBSET-037, mainly the priority management of communication resources (new section 8.5) and need not any further discussion.

Regarding the action 14.06 (To draft a list with all the abbreviations/definitions/acronyms to be incorporated in SUBSET-023 concerning CR 0741 and CR 1237):

The paper drafted by U is not reviewed (lack of time). However it is expected that its content is not controversial and it will be reviewed after the meeting by ERA and most likely incorporated as such in the SUBSET-023. Any further comment will then be addressed in the frame of the B3R2 documentation review round.

Others:

In addition the modifications to the following other documents have been overlooked so far:

SUBSET-026 chapter 2 figure 1: wherever the labels SUBSET-114 and SUBSET-038 are present, the label SUBSET-137 must be added

SUBSET-104 table 4.3.2: a new line “SUBSET-137” needs also to be added with an “N” in the “Impacting” column.

1265 Miscellaneous editorial findings in B3 MR1

New items are added due to feedback from the Test Spec WG and on request by U (e-mails 30/10/2015, 31/10/15 and 03/11/15). All these new items are discussed and agreed. See rows highlighted in yellow in the embedded file below.

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Regarding the item about the term “ongoing” (unduly spelled “on-going” in some documents), it is agreed to incorporate it for the 4 documents that could be identified during the meeting (S26, DMI, S35 and S39).

It is agreed to stop taking into consideration new items and to close the CR with the batch of items agreed during the meeting, with only one exception: U will investigate whether there are other documents, to be anyway updated for B3R2, where the correction could be brought.

Action 15.03b U (10/11/15): to investigate whether the term “ongoing”, incorrectly spelled “on-going”, can be found in documents (in addition to S26, DMI, S35 and S39) to be updated for B3R2 for other reasons.

Post meeting note: in line #31 of the sheet “S26”, the section number has been corrected from 6.3.1.3 to 6.3.1.2.

1266 Classification of SRS requirements

The comments from U (28/10/15) on chapter 2 and 6 classification are discussed and agreed. See cells highlighted in blue in the embedded file below.

After this last review round, the agreed classification for the SRS 340 is successfully achieved.

Post meeting note: the cells “SRS modification” in ch3 lines 523 and 1709 are also slightly amended

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(implementation issue in SRS 3.4.2)

The next step will consist in re-iterating the classification exercise for either the modified clauses or the added new clauses brought in the SRS 3.4.2.

Action 15.04 ERA (ASAP): to propose the classification of the clauses updated/added in the SRS 3.4.2.

The EUG comment (30/10/15) on SUBSET-026 chapter 9 clause 9.2.3.2 is then discussed. ERA recalls that the “primary” purpose of the classification exercise is to isolate the on-board requirements, which consequently also consists in identifying indirectly the trackside requirements (also identified with the keyword “shall”) and the clauses which do not belong to any of these two categories. ERA also observes that there might be some tables classified as requirement, which do not actually include the keyword “shall”. It is therefore wondered whether the chapter 1 clause 1.7.1.1 should not have been amended to reflect the outcome of the classification exercise.

Action 15.05 ERA (ASAP): To reflect on how the chapter 1 should be amended to coherently reflect the classification.

1278 SUBSET-074 upgrade to Baseline 3 Release 2 (B3R2)

The CR is closed, since the updated SUBSET-074 posted by U on 20/10/15 implements all the modifications agreed during the last October EECT meeting.

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4. Baseline Compatibility Analysis

The BCA exercise is resumed and completed for the sheets “B3.1 definition” and “B3 MR1 maintenance”, see embedded file below.

Regarding the CR 1249:

EUG justification for Q1 answer “no”:

EUG argues that some of their members still believe that only the lambda needs to be considered when checking whether a train can fit a line for what concerns the maximum tolerable braking distance and that the introduction of a configurable indication time makes the braking distance not controllable by trackside.

ERA reminds again that for instance the guidance curve, left to the RU’s discretion, influences also the braking distance. EUG remarks that the guidance curve can be inhibited by the trackside (National Value). Although the existence of this National Value is highly questionable from interoperability point of view, ERA replies that even if used there are still other degrees of freedom for the RU (e.g. interface to Service Brake implemented or not) which will make the braking distance depending not only from the lambda value, not speaking of the case of gamma trains.

Therefore ERA stresses that to rely only the lambda might be still true for non ETCS systems but this is undoubtedly wrong with ETCS and its highly configurable and sophisticated on-board braking model. Therefore it is again recalled what was exhaustively explained in the minutes of the September meeting: “....the indication time represents only a small contribution to the overall braking distance calculated by the on-board equipment, which depends on many other parameters (nominal emergency braking deceleration values, on-board correction factors, guidance curve, calculation of the lambda, etc...) relying upon the Railway Undertaking itself.”

U justification for Q1/Q2 answer “no:

U explains that some trackside implementations (regarding the LX closure function) rely on some kind of not flexible braking distance window (not only a maximum braking distance but also a minimum braking distance would be required) and that a B3R2 train whose MA request would be triggered 7 s later than the same train equipped with B3R1 could fail to comply some National Rules for minimum LX closure warning times. ERA is strongly surprised that such engineering could have seen the light, because it would de facto make impossible the operation of a train performing better than those ones for which this non ETCS function is tailored.

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Conclusion: it is confirmed (ERA decision) that the CR1249 is an on-board CR (Q1=yes, Q2= N/A), dealing only with driver’s ergonomics.

Regarding the CR1265

After discussion it is agreed that the modifications to T_NVCONTACT (line 44 in document “Misc_editorial_findings_in_B3MR1_v6.xlsx") are more than editorial, because in the current baselines (B2 and B3MR1) it can still be interpreted that the reference message for the T_NVCONTACT could be either a high priority message or not, while the CR1265 line 44 intends to clarify that it is only normal priority messages. The concerned line is therefore removed (see embedded file in section 3 - CR1265) and the answers to Q1/Q2 is set to N/A. In addition, U will submit a new CR to be considered for a further release.

Conclusion

ERA wraps up the BCA for the 53 CRs whose solutions have been worked out in the frame of the B3R2 programme. It is also underlined that this BCA exercise has been carried out with strict and constant criteria, which consist of the application of the SUBSET-104 provisions. In particular only the specifications have been taken into account and not any project or product specific considerations.

Amongst these 53 CRs, there are 5 CRs with a “No” for Q1 and/or Q2. However ERA explains that at this stage the intention is to keep all the CRs initially included in the basket and to incorporate them in the SRS 3.4.2 and the other subdocuments to be delivered mid November.

The way the “paper” incompatibility of these five CRs will be tackled will be announced later.

5. AOB

Use of term “Optional” for trackside versus “optional” for on-boardLike the Test Spec WG, U has also perceived the difference between the term optional for a track-to-train packet (i.e. it is a design/implementation choice) and the term optional for train-to-track packet (i.e. it is mandatory to send it, depending on the context/circumstances), which does not look appropriate. A similar issue has been fixed for a specific RBC-RBC message in the frame of the CR299 (use of the term “additional” instead). ERA however states that it is not a pure editorial modification and that it will have to be tackled after the B3R2. CR 1117The Test Spec WG has spotted a flaw in the solution. They made a reading of the clause 3.5.3.7 a) as not having any exception and being contradicted by 3.5.3.9.1. Actually, the last minute withdrawal (on request by U) of the introductory sentence proposed by ERA has led to this misunderstanding. ERA therefore announces that the CR will be reopened to fix this.Action 15.06 ERA (ASAP): to reopen the CR1117 and draft an amended solution. EVC definitionU points out that the abbreviation “EVC” exists in the SUBSET-023 but there is no corresponding definition. This definition is important for the DMI-EVC interface. ERA considers that the term EVC has been kept in the SUBSET-023 just because there were still a

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few occurrences in some subdocuments that could not be substituted easily. Furthermore, there is a definition of “vital” in the SUBSET-023 which makes the definition of EVC most likely unnecessary.

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Attendance list

First Name Surname Organisation Signature E-mail address

Olivier GEMINE ERA [email protected]

Alain HOUGARDY ERA [email protected]

Oscar REBOLLO BRAVO ERA [email protected]

(only day 2)

DOMINGO ERA [email protected]

Ron BAILES CER [email protected]

Rob DIJKMAN ERTMS U.G. [email protected]

Roman TREYDEL ERTMS U.G. [email protected]

Alfonso (only day

1)LORENZO ERTMS U.G. [email protected]

Sharvind (only day

2)APPIAH ERTMS U.G. [email protected]

Aidan (only day 2) MCGRADY ERTMS U.G. [email protected]

Philippe PRIEELS UNIFE/UNISIG [email protected]

Luca REPETTI UNIFE/UNISIG [email protected]

Jakub MAREK UNIFE/UNISIG [email protected]

Frank (only day 2) KAISER UNIFE/

UNISIG [email protected]

François HAUSMAN UNIFE/UNISIG [email protected]

Ingo (only day 2) WENDLER UIC [email protected]

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