Re: [ipwave] LTE-V2X term in Problem Statement document

[Alexandre Petrescu <[e-mail]>]

Le 17/04/2019 à 15:25, Jérôme Härri a écrit :
> Dear Dirk,
> 
> Thanks. I guess we replied with similar thoughts. Now, on your 
> definition, I would also avoid using this:
> 
> LTE-V2X: the transmission of ETSI CAM and DENM messages over IP over a 
> cellular link such as 3GPP 4G – both via base station and directly 
> between vehicles
> 
> JHNOTE: we should not link CAM/DENM on LTE-V2X…these are layered 
> aspect…LTE-V2X can take whatever comes from higher layers, as long as it 
> is packet-based (no streams) and (most likely) periodical (from the 
> semi-persistent scheduling of the LTE Slidelink V2X scheduler), even if 
> this last point can be discussed.
> 
> C-V2X: the transmission of ETSI CAM and DENM messages over IP over a 
> cellular link such as 3G, 4G and successors – both in infrastructure 
> mode (via base station / Uu interface) and ad-hoc mode (direct link / 
> sidelink interface) if available [since sidelink is only specified for 
> 4G/5G]
> 
> JHNOTE: I think we should not use C-V2X, as the denomination ‘C’ is for 
> ‘Cellular’, which might not be fully the case (e.g. LTE Prose mode 4, 
> a.k.a V2X)

Is C-V2X term already defined by Qualcomm?  Or by another SDO?

Alex

> 
> Best Regards,
> 
> Jérôme
> 
> *From:*its [mailto:[e-mail]] *On Behalf Of 
> *[e-mail]
> *Sent:* Wednesday 17 April 2019 14:32
> *To:* [e-mail]; [e-mail]
> *Subject:* Re: [ipwave] LTE-V2X term in Problem Statement document
> 
> Hi Alex,
> 
> I strongly agree with you that we need a precise definition on what we 
> mean with cellular V2X (often denoted as C-V2X in general – so covering 
> LTE and 5G/NR) – especially since – as you correctly pointed out - 3GPP 
> has none such official definition as LTE-V2X or NR-V2X .
> 
> However when defining LTE-V2X we should be aware that there are two 
> different modes of operation for V2X communication in 3GPP cellular 
> systems (as also described in Annex A.5 of PS document 
> https://tools.ietf.org/html/draft-ietf-ipwave-vehicular-networking-08).
> 
> E.g. according to 3GPP TR 21.914 giving a Release 14 (i.e. LTE) 
> Description and Summary of Rel-14 Work Items, but similarly also for 
> 5G/NR or Rel. 15 and higher (here in still draft TR 21.915) the modes of 
> operation are described as
> 
> -Direct V2X communication between UEs over a 3GPP sidelink (PC5 interface)
> 
> -V2X communication over LTE-Uu interface (i.e. via base stations / eNBs)
> 
> In addition there are 2 different modes for PC5/sidelink:
> 
> -in coverage of cellular system with LTE assistance
> 
> -out of coverage: ad-hoc mode w/o assistance … very similar to OCB.
> 
> So I would recommend to specify more exactly what we have in mind.
> 
> LTE-V2X: the transmission of ETSI CAM and DENM messages over IP over a 
> cellular link such as 3GPP 4G – both via base station and directly 
> between vehicles
> 
> Or more general:
> 
> C-V2X: the transmission of ETSI CAM and DENM messages over IP over a 
> cellular link such as 3G, 4G and successors – both in infrastructure 
> mode (via base station / Uu interface) and ad-hoc mode (direct link / 
> sidelink interface) if available [since sidelink is only specified for 
> 4G/5G]
> 
> Or one may even reflect differentiation between those modes in the 
> acronym (which I would not recommend here being not in scope for this 
> document)
> 
> Just my 2 cents
> 
> Kind regards
> 
> Dirk
> 
> *From:*its <[e-mail]> *On Behalf Of *Alexandre Petrescu
> *Sent:* Mittwoch, 17. April 2019 13:18
> *To:* [e-mail]
> *Subject:* [ipwave] LTE-V2X term in Problem Statement document
> 
> Hi IPWAVErs,
> 
> The IPWAVE Problem Statement document uses the term 'LTE-V2X' at one 
> point. ("e.g., IEEE 802.11-OCB and LTE-V2X")
> 
> I would like to suggest to make a careful definition of the term 'LTE-V2X'.
> 
> One would expect the term 'LTE-V2X' to be defined precisely at 3GPP or 
> similar.  But that is not the case.  The 3GPP document that is closest 
> to this term is RP-161298, publicly available, defines the term 
> 'LTE_V2X' (remark underscore '_', instead of dash '-').
> 
> I suggest the addition of the following term in the Problem Statement draft:
> 
> LTE-V2X: the transmission of ETSI CAM and DENM messages over IP over a 
> cellular link such as 3G, 4G and successors.
> 
> Alex
>