In once sense, the statement is inherently true. A VPN technology
without underlay support would seem to have significant difficulty in
consistently meeting an SLA. Having said that much, the rest does not
seem to follow.
Yours,
Joel
On 3/26/2020 1:40 AM, [email protected] wrote:
Hi, Joel,
The statement is that pure overlay VPNs cannot meet the requirement of
some new services, and it would require integration between the underlay
and the overlay networks.
As mentioned in this document, there is existing technology in the
underlay to support enhanced VPNs , such as using a set of MPLS-TE based
resource reserved point-to-point paths, while it scalability is the
concern of many operators.
Thus VTN is introduced to provide the required topology and resource
attribute in the underlay in a scalable manner. This is described in the
introduction section.
Hope this helps.
Chongfeng
*From:* Joel M. Halpern <mailto:[email protected]>
*Date:* 2020-03-25 21:52
*To:* [email protected] <mailto:[email protected]>; lsr
<mailto:[email protected]>
*Subject:* Re: [Lsr] Using IS-IS Multi-Topology (MT) for Segment
Routing based Virtual Transport Network
This drafts starts by asserting that there are limitations on what can
be done with the existing technology. As the description is quite
vague, I can not be certain. But I do not know of any difficulty in
providing the described capabilities with current technology, without
introducing a new, undescribed, construct called a VTN.
Yours,
Joel
On 3/25/2020 9:44 AM, [email protected] wrote:
>
> Hello, folks,
>
> we have submitted a new draft of
> https://tools.ietf.org/html/draft-xie-lsr-isis-sr-vtn-mt-00 .
>
> It is about Using IS-IS Multi-Topology (MT) for Segment Routing
based
> Virtual Transport Network. Enhanced VPN (VPN+) as defined in
> I-D.ietf-teas-enhanced-vpn aims to provide enhanced VPN service to
> support some applications's needs of enhanced isolation and
stringent
> performance requirements. VPN+ requries integration between the
overlay
> VPN and the underlay network. A Virtual Transport Network (VTN)
is a
> virtual network which consists of a subset of the network toplogy
and
> network resources allocated from the underlay network. A VTN
could be
> used as the underlay for one or a group of VPN+ services.. This
document
> describes a simplified mechanism to build the SR based VTNs using
IGP
> multi- topology together with other well-defined IS-IS extensions.
>
> Comments and suggestions are highly appreciated.
>
> Chongfeng Xie
>
>
>
> _______________________________________________
> Lsr mailing list
> [email protected]
> https://www.ietf.org/mailman/listinfo/lsr
>
_______________________________________________
Lsr mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/lsr
_______________________________________________
Lsr mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/lsr
_______________________________________________
Lsr mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/lsr
