Re: [Teas-ns-dt] Comment to definitions draft in today's call -- logical vs abstract vs virtual

[Adrian Farrel <[e-mail]>]

This is, indeed, the service consumer’s view of a slice, and John is right.

 

The other view is the view seen by the operator delivering the slicing service. They, of course, have to partition resources.

 

I think there is value in separating these two views and describing them distinctly.

 

To possibly build on what John says, when we deliver connectivity as a service, the service user has no visibility into the way that the connectivity is provided. On the other hand, when we deliver a network as a service, we allow the consumer control of the delivered network.

 

Now, we can debate the merits of these different services until the proverbial ruminants return to the domestic environment, but while some people may want to deliver one type of service only, that doesn’t prevent others from wanting to deliver the other kind of service.

 

If we separate the views and descriptions instead of trying to put everything in one pot, we may manage to make progress.

 

Adrian

 

From: Teas-ns-dt <[e-mail]> On Behalf Of John E Drake
Sent: 06 March 2020 19:24
To: Kiran Makhijani <[e-mail]>
Cc: LUIS MIGUEL CONTRERAS MURILLO <[e-mail]>om>; Dongjie (Jimmy) <[e-mail]>om>; Eric Gray <eric.gray=[e-mail]>rg>; Belotti, Sergio (Nokia - IT/Vimercate) <[e-mail]>om>; Jeff Tantsura <[e-mail]>om>; [e-mail]
Subject: Re: [Teas-ns-dt] Comment to definitions draft in today's call -- logical vs abstract vs virtual

 

Hi, 

 

I think this whole discussion of topologies is ill-considered.  We have a set of endpoints and a set of SLOs.  We neither know nor care how the connectivity between the endpoints is achieved.

 

Sent from my iPhone





On Mar 5, 2020, at 9:50 PM, Kiran Makhijani <[e-mail]> wrote:

 

There is one more way to see through this.

If you agree that all justifications on this thread are right,  then all or any of these terms (virtual, logical, real, etc.) are correct usage based on your perspective. What does not change is that it “is a network topology”,  “has end points” , “has network resources., and “connects with expected SLOs” – we all seem to converge on this much text.

 

Can we say:

"A transport slice is a [description] of network topology connecting a number

   of endpoints and a set of shared or dedicated network resources,

   which are used to satisfy specific Service Level Objectives (SLO)".

Or simply,

"A transport slice is a network topology….”

 

Would you accept just one word change from logical to some other noun or nothing [] at all? Words that come to my mind are depiction, representation, description…

 

-Kiran

 

From: Teas-ns-dt <[e-mail]> on behalf of "Dongjie (Jimmy)" <[e-mail]>
Date: Thursday, March 5, 2020 at 6:12 PM
To: Jeff Tantsura <[e-mail]>om>, Eric Gray <eric.gray=[e-mail]>
Cc: LUIS MIGUEL CONTRERAS MURILLO <[e-mail]>om>, "Belotti, Sergio (Nokia - IT/Vimercate)" <[e-mail]>om>, "[e-mail]" <[e-mail]>
Subject: Re: [Teas-ns-dt] Comment to definitions draft in today's call -- logical vs abstract vs virtual

 

Hi all,

 

As mentioned on the conference call, my preference of the terms would be virtual >= logical > abstract. 

 

IMO all of these terms refer to something not totally physical or “real”. Actually this is what is expected from network slicing, multiple network slices are built on a shared physical network infrastructure, and each network slice is provided with a subset of the characteristics of the underlying network.

 

To me virtual and logical can be seen as similar terms and sometimes interchangeable. Virtual has been used widely in IETF and industry, which makes it easier for people to associate “virtual” with specific implementations, although it can be a technology-agnostic term. Logical can be considered more comprehensive, the other side of which may be is more vague.  That said, both would be OK for the definition.

 

As for abstract, as explained in my previous mails, “abstract” is more related to the policy used to provide the consumer with a selective view of the network, which is mainly about the NBI, while in the definition we may also want to cover the characteristics of the transport slice itself. 

 

Best regards,

Jie

 

From: Teas-ns-dt [mailto:[e-mail]] On Behalf Of Jeff Tantsura
Sent: Friday, March 6, 2020 3:03 AM
To: Eric Gray <eric.gray=[e-mail]>
Cc: LUIS MIGUEL CONTRERAS MURILLO <[e-mail]>om>; Belotti, Sergio (Nokia - IT/Vimercate) <[e-mail]>om>; [e-mail]
Subject: Re: [Teas-ns-dt] Comment to definitions draft in today's call -- logical vs abstract vs virtual

 

+1 to “logical”

Regards,

Jeff







On Mar 5, 2020, at 10:06, Eric Gray <eric.gray=[e-mail] <mailto:eric.gray=[e-mail]> > wrote:

Yes, the separation of virtual and real is a big part of the “freight” that “virtual” carries.

 

At a “Disruptive Technologies” class given at AT&T decades ago, the teacher told us “Whenever you hear ‘virtual’ – you should interpret this as ‘I am lying.’”

 

This is only a perception thing, but that does not mean it is not just as real as if it were real.  In way too many cases, virtual is used explicitly to distinguish it from reality.  For example, “virtual reality” is pretty much never considered to include “real reality.”  😊

 

I tend to prefer “logical” in this context, over either “virtual” or “abstract” – in no small part because “abstract” also has “freight.” “Abstract” is often considered to be similar in meaning to “surreal” – which is very unlikely to be what we mean by an “abstract topology” for example.  I cannot wrap my head around the notion of a network designed (for instance) by either Salvador Dali, or M.C. Escher.

 

But these are minor preferences.  With the exception of context-related cases (where we need to use the terminology that fits best in a given context), I think we should try to be consistent and I am fine with any term everyone can live with.

 

From: Teas-ns-dt <[e-mail] <mailto:[e-mail]> > On Behalf Of Belotti, Sergio (Nokia - IT/Vimercate)
Sent: Thursday, March 5, 2020 12:35 PM
To: LUIS MIGUEL CONTRERAS MURILLO <[e-mail] <mailto:[e-mail]> >; [e-mail] <mailto:[e-mail]> 
Subject: Re: [Teas-ns-dt] Comment to definitions draft in today's call -- logical vs abstract vs virtual

 

I think that logical (or even abstract) is more comprehensive since virtual reminds to some kind of virtualization of the underlying resources, but a slice could naturally involve (dedicated) physical resources. So that is why I'm inclined to use logical as a more generic term.

 

Virtualization has nothing to do with “select” only physical resources but instead is related to select underlying resources (physical or abstract) in the prospective to a particular customer, application or service.

If this was your problem with virtual , it is not a problem.

 

Regards

SErgio

 

From: Teas-ns-dt <[e-mail] <mailto:[e-mail]> > On Behalf Of LUIS MIGUEL CONTRERAS MURILLO
Sent: Thursday, March 5, 2020 6:12 PM
To: [e-mail] <mailto:[e-mail]> 
Subject: [Teas-ns-dt] Comment to definitions draft in today's call -- logical vs abstract vs virtual

 

Hi all,

 

Apologies, I experienced problems in the call today, not being able for me to speak up (even I lost part of the discussions, apologies again).

 

I wrote my preference in the chat, I think you couldn’t echoed.

 

So respect to the discussion of preference for logical  vs abstract vs virtual, I think that logical (or even abstract) is more comprehensive since virtual reminds to some kind of virtualization of the underlying resources, but a slice could naturally involve (dedicated) physical resources. So that is why I'm inclined to use logical as a more generic term.

 

Note that in the operators’ vocabulary today “virtual” has further connotations (exceeding the transport part), so can be an overloaded term in some end-to-end scenarios.

 

Best regards

 

Luis

 

 

__________________________________

Luis M. Contreras

 

Technology and Planning

Transport, IP and Interconnection Networks

Telefónica I+D / Global CTIO unit / Telefónica

 

Distrito Telefónica, Edificio Sur 3, Planta 3

28050 Madrid

España / Spain

 

Skype (Lync): [phone]

Mobile: [phone]

 <mailto:[e-mail]> [e-mail]

 

 

 

  _____  


Este mensaje y sus adjuntos se dirigen exclusivamente a su destinatario, puede contener información privilegiada o confidencial y es para uso exclusivo de la persona o entidad de destino. Si no es usted. el destinatario indicado, queda notificado de que la lectura, utilización, divulgación y/o copia sin autorización puede estar prohibida en virtud de la legislación vigente. Si ha recibido este mensaje por error, le rogamos que nos lo comunique inmediatamente por esta misma vía y proceda a su destrucción.

The information contained in this transmission is privileged and confidential information intended only for the use of the individual or entity named above. If the reader of this message is not the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this transmission in error, do not read it. Please immediately reply to the sender that you have received this communication in error and then delete it.

Esta mensagem e seus anexos se dirigem exclusivamente ao seu destinatário, pode conter informação privilegiada ou confidencial e é para uso exclusivo da pessoa ou entidade de destino. Se não é vossa senhoria o destinatário indicado, fica notificado de que a leitura, utilização, divulgação e/ou cópia sem autorização pode estar proibida em virtude da legislação vigente. Se recebeu esta mensagem por erro, rogamos-lhe que nos o comunique imediatamente por esta mesma via e proceda a sua destruição

-- 
Teas-ns-dt mailing list
[e-mail] <mailto:[e-mail]> 
https://www.ietf.org/mailman/listinfo/teas-ns-dt <https://urldefense.com/v3/__https:/nam11.safelinks.protection.outlook.com/?url=https*3A*2F*2Fwww.ietf.org*2Fmailman*2Flistinfo*2Fteas-ns-dt&data=02*7C01*7Ckiranm*40futurewei.com*7Cb1af646b98964059a12a08d7c173c8f4*7C0fee8ff2a3b240189c753a1d5591fedc*7C1*7C0*7C637190575362578900&sdata=bFZt54vrP6zJmHLlXNd4Zf6dWGlXjz27C3vGFOfDMNw*3D&reserved=0__;JSUlJSUlJSUlJSUlJSUl!!NEt6yMaO-gk!SIiOm_tVxNrchKJcUFQ5QdflPoYyiOzHtDGUtFAC9tXpo8WkbDC5s-C-IU4VAlg$> 

-- 
Teas-ns-dt mailing list
[e-mail]
https://urldefense.com/v3/__https://www.ietf.org/mailman/listinfo/teas-ns-dt__;!!NEt6yMaO-gk!SIiOm_tVxNrchKJcUFQ5QdflPoYyiOzHtDGUtFAC9tXpo8WkbDC5s-C-p3WqCVY$