Re: [Teas] network Slice Endpoint in draft-ietf-teas-ietf-network-slice-definition-00

[John E Drake <[e-mail]>]

Hi,

Comment inline

Yours Irrespectively,

John



Juniper Business Use Only
From: Teas <[e-mail]> On Behalf Of Rokui, Reza (Nokia - CA/Ottawa)
Sent: Wednesday, February 10, 2021 7:39 AM
To: [e-mail]; 'Joel M. Halpern' <[e-mail]>; [e-mail]
Cc: Rokui, Reza (Nokia - CA/Ottawa) <[e-mail]>
Subject: Re: [Teas] network Slice Endpoint in draft-ietf-teas-ietf-network-slice-definition-00

[External Email. Be cautious of content]


Joel and Adrian,



Agreed that there shall be clarity about the endpoints.



                >>>>>> There are traffic endpoints (the sender and receiver of packets), and there are endpoints of the service (the ingress and egress to the slice).

This is correct Adrian.



An “IETF network slice” is between two or more endpoints as outlined in the draft.

In summary, the  IETF network slice is defined  between various device/applications/network functions on multiple “IETF network slice endpoints”.  These are traffic endpoints of the IETF network slice. We refer to them in the draft as “NSE” (IETF Network Slice Endpoints).

In addition , as Adrian mentioned there are endpoints to the realization of the transport slice (i.e. various services/tunnels/paths). I am suggesting to use term “NSI” (IETF Network Slice Ingress).  Please provide your suggestions for NSI if you have any other suggestions.



                >>>> For example, if the service is being

    delivered with MPLS, the Network Slice Endpoint likely cannot put the

    labels on the packet for the MPLS, as it is outside of the IETF network

    Slice.  So we will need yet another layer of classification, and yet

    more interworking.



This is not correct.  Whatever technology is used to realize the IETF network slice must be supported by endpoints. If MPLS is technology of choice, the endpoint must support it in its data-path (and might also support it in its control-plane).



[JD]  This is incorrect.   E.g., in IETF VPNs, the traffic from the CE to the PE is *not* MPLS encapsulated.  It is the PE that does the encapsulation.



Cheers,



Reza



    ------------------Original Message-----------------------



On 2021-02-05, 5:29 PM, "Teas on behalf of Adrian Farrel" <[e-mail] on behalf of [e-mail]<mailto:[e-mail][e-mail]>> wrote:



    Ah, the old "endpoint" discussion.



    Yes, Joel is right, we need to disambiguate endpoints from endpoints.

    There are traffic endpoints (the sender and receiver of packets), and there

    are endpoints of the service (the ingress and egress to the slice).



    There is probably a risk that we get sucked in to the wider 5G picture, but

    we need to focus (as Joel says) on the IETF network slice.



    I suggest "source/destination" and "IETF network slice ingress/egress".



    And we can avoid discussion of the wider 5G context, as noted elsewhere in

    the draft, by diverting that material into a dedicated document.



    Cheers,

    Adrian



    -----Original Message-----

    From: Teas <[e-mail]<mailto:[e-mail]>> On Behalf Of Joel M. Halpern

    Sent: 05 February 2021 17:04

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

    Subject: [Teas] network Slice Endpoint in

    draft-ietf-teas-ietf-network-slice-definition-00



    Rereading this draft, I realized that I am either confused by or

    disagree with the description of the "Network Slice Endpoint" contianed

    there.





    The endpoint that I think matters is the place where the IETF Network

    Slice Controller starts controlling the QoS and traffic delivery.  The

    Controller doesn't care about the identity of the device outside of that.



    Figure 1 in section 4.2 seems to define that endpoint as the network

    slice realiation endpoint, and describes the network slice endpoint as

    the thing outside the IetF network slice.  This seems counter-productive

    to me.  It complicates teh relationship between the endpoitn and the

    service being abstracted.  For example, if the service is beign

    delivered with MPLS, the Network Slice Endpoint likely can not put the

    labels on the packet for the MPLS, as it is outside of the IETF network

    Slice.  So we will need yet another layer of classification, and yet

    more interworking.

    Further, someone has to get the queueing right for traffic coming out of

    the Network Slice Endpoint.  But it is not part of the IETF Network

    Slice, so we don't have any way to get it right.



    If we define the edge of the space we care about co-incident with the

    edge of the space we influence, things get a lot cleaner.



    Yours,

    Joel



    _______________________________________________

    Teas mailing list

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

    https://www.ietf.org/mailman/listinfo/teas



    _______________________________________________

    Teas mailing list

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

    https://www.ietf.org/mailman/listinfo/teas