Thank you Linda. I'll request LC

G/
________________________________
From: Linda Dunbar <[email protected]>
Sent: Tuesday, April 7, 2026 8:20 PM
To: Gunter van de Velde (Nokia) <[email protected]>; 
[email protected] 
<[email protected]>
Cc: BESS <[email protected]>; Matthew Bocci (Nokia) <[email protected]>
Subject: RE: [Shepherding AD review] review of 
draft-ietf-bess-bgp-sdwan-usage-29


CAUTION: This is an external email. Please be very careful when clicking links 
or opening attachments. See the URL nok.it/ext for additional information.



Gunter,



Thank you, the revision that has included the resolutions to your comments has 
been uploaded: https://datatracker.ietf.org/doc/draft-ietf-bess-bgp-sdwan-usage/



Linda



From: Gunter van de Velde (Nokia) <[email protected]>
Sent: Tuesday, April 7, 2026 1:52 AM
To: Linda Dunbar <[email protected]>; 
[email protected]
Cc: BESS <[email protected]>; Matthew Bocci (Nokia) <[email protected]>
Subject: Re: [Shepherding AD review] review of 
draft-ietf-bess-bgp-sdwan-usage-29



Thanks Linda. Once updated I'll process for the next steps in the lifecycle of 
the document.



Be well,

G/





________________________________

From: Linda Dunbar 
<[email protected]<mailto:[email protected]>>
Sent: Friday, April 03, 2026 5:40 PM
To: Gunter van de Velde (Nokia) 
<[email protected]<mailto:[email protected]>>; 
[email protected]<mailto:[email protected]>
 
<[email protected]<mailto:[email protected]>>
Cc: BESS <[email protected]<mailto:[email protected]>>; Matthew Bocci (Nokia) 
<[email protected]<mailto:[email protected]>>
Subject: RE: [Shepherding AD review] review of 
draft-ietf-bess-bgp-sdwan-usage-29





CAUTION: This is an external email. Please be very careful when clicking links 
or opening attachments. See the URL nok.it/ext for additional information.



Gunter,



Thank you very much for the valuable comments.



Please see below after [Linda] for the resolutions.



Linda



From: Gunter van de Velde (Nokia) 
<[email protected]<mailto:[email protected]>>
Sent: Thursday, April 2, 2026 1:32 AM
To: 
[email protected]<mailto:[email protected]>
Cc: BESS <[email protected]<mailto:[email protected]>>; Matthew Bocci (Nokia) 
<[email protected]<mailto:[email protected]>>
Subject: [Shepherding AD review] review of draft-ietf-bess-bgp-sdwan-usage-29



Hi Authors, WG,



# Gunter Van de Velde, RTG AD, comments for draft-ietf-bess-bgp-sdwan-usage-29



# line numbers are rendered from the idnits tool found at 
https://author-tools.ietf.org/api/idnits?url=https://www.ietf.org/archive/id/draft-ietf-bess-bgp-sdwan-usage-29.txt



# Many thanks for the shepherd writeup from Matt Bocci, and thanks for the 
routing directorate reviews from Shuping Peng and Alvaro Retana.



# Authors, many thanks for all the hard work on this draft. It came a long way. 
My generic comments are mostly of editorial nature.



# Running idnits identifies a set of unused references, please resolve with the 
next version.



# once an update draft is posted, I'll start processing for IETF LC on this 
informational track document.



#GENERIC COMMENTS

#================



140      plane information. In this document, references to "the RR" denote

141      the RR instance(s) designated by the SD-WAN controller to

142      distribute SD-WAN routing information. Deployments may integrate



GV> in section 2 is controller explained and RR introduced. However that comes 
after this specific usage of the term RR. Is this intentional or can the the 
term RR be expanded at first usage?



[Linda] Good catch. This was not intentional. We will expand RR to “Route 
Reflector (RR)” at first use in the Introduction.



Old:

“In this document, references to “the RR” denote the RR instance(s) designated 
by the SD-WAN controller to distribute SD-WAN routing information”



New:

“In this document, references to “the Route Reflector (RR)” denote the RR 
instance(s) designated by the SD-WAN controller to distribute SD-WAN routing 
information.”



165   2. Conventions used in this document



GV> many terms are explained in this section. Could the RR be explicitly 
mentioned in this list also and how it relates to sd-wan. I know its embroided 
in other terminologies, but since the term i suse dso often it maybe makes 
sense to say few words about it.



170      Controller: Used interchangeably with SD-WAN controller to denote

171                  the logical system that manages the SD-WAN overlay

172                  network. In the context of BGP-controlled SD-WAN, one

173                  function of the SD-WAN controller is to provide BGP-

174                  based route propagation, i.e., the Route Reflector

175                  (RR) function. This RR function may be collocated with

176                  or embedded within the SD-WAN controller, but

177                  represents only one component of the overall SD-WAN

178                  controller.



180      the SD-WAN controller functions are integrated with the BGP Route

181                  Reflector (RR).



GV> Line 180 may have an editorial tab issue. (it starts at the same character 
space as Controller)



[Linda] How about the following text change:

Old:



Controller: Used interchangeably with SD-WAN controller to denote the logical 
system that manages the SD-WAN overlay network. In the context of 
BGP-controlled SD-WAN, one function of the SD-WAN controller is to provide 
BGP-based route propagation, i.e., the Route Reflector (RR) function. This RR 
function may be collocated with or embedded within the SD-WAN controller, but 
represents only one component of the overall SD-WAN controller.



The SD-WAN controller functions: are integrated with the BGP Route Reflector 
(RR).



New:

Controller: Used interchangeably with SD-WAN controller to denote the logical 
system that manages the SD-WAN overlay network. In a BGP-controlled SD-WAN, the 
controller may include a Route Reflector (RR) function for BGP route 
propagation and policy-based distribution of SD-WAN routing information. The RR 
function may be collocated with, embedded in, or otherwise integrated with the 
SD-WAN controller, but it represents only one component of the overall 
controller.





762     - Update 1: Client Route Advertisement for advertising the

763        prefixes of client services attached to the client facing

764        interfaces. The Section 8 of [RFC9012] (Recursive Next-Hop

765        Resolution) can be used to associate each client service with

766        the corresponding WAN ports for the desired underlay paths.

767     - Update 2: Underlay WAN Port Advertisement, which conveys

768        information about the underlay WAN facing interfaces of an SD-

769        WAN edge, including attributes such as IPsec SA parameters, MPLS

770        label stacks, and other relevant attributes. These attributes

771        are carried in the BGP Tunnel Encapsulation Attribute, along

772        with associated Color values that allow BGP receivers to

773        correlate the WAN facing interfaces with the client routes

774        advertised in Update 1.



GV> I think i understand the high level processing, i do believe that adding a 
diagram may explain more clearly/accuratly the intent of each bgp route.

Note that "underlay wan port" is not mentioned in the convention section



[Linda] We believe the existing Figure 6 (Section 5.2) already illustrates the 
roles of the two BGP UPDATEs and the relationship among the client routes, the 
SD-WAN edge, and the RR. Instead of adding another figure, we can revise the 
text in Section 5.3 to refer readers to Figure 6 and to make the distinct roles 
of the two BGP UPDATEs clearer, including how they are associated through 
recursive next-hop resolution.

New:

Update 1: Client Route Advertisement. This UPDATE advertises the prefixes of 
client services attached to the client-facing interfaces of an SD-WAN edge. As 
described in Section 8 of [RFC9012], recursive next-hop resolution can be used 
to associate each client route with the appropriate WAN-facing interface(s) of 
the advertising SD-WAN edge for the desired underlay path. Figure 6 illustrates 
the relationship among the client routes, the SD-WAN edge, and the RR.



Update 2: WAN-Facing Interface Advertisement. This UPDATE advertises 
information about the WAN-facing interfaces of an SD-WAN edge that connect to 
the underlay networks, including attributes such as IPsec SA parameters, MPLS 
label stacks, and other relevant underlay properties. These attributes are 
carried in the BGP Tunnel Encapsulation Attribute, together with associated 
Color values, allowing BGP receivers to associate the advertised WAN-facing 
interfaces with the client routes advertised in Update 1. Figure 6 also 
illustrates the SD-WAN edge WAN ports that are the basis for this advertisement.



815      BGP UPDATE #1a: Propagated only to the Payment Gateway node for a

816      point-to-point (P2P) topology between the Payment Application and

817      the Payment Gateway.

818

819      BGP UPDATE #1b: Propagated to C-PE1 and C-PE3 for other prefixes

820      that can be reached by these edge nodes.



GV> the text reads 'propagated only to' but does not document which devices are 
originating the BGP UPDATE?



[Linda] How about changing the wording to the following:

BGP UPDATE #1a: Originated by the SD-WAN edge attached to the Payment 
Application and propagated by the RR only to the Payment Gateway node, thereby 
creating a point-to-point (P2P) topology between the Payment Application and 
the Payment Gateway.



BGP UPDATE #1b: Originated by the same SD-WAN edge for other prefixes and 
propagated by the RR to C-PE1 and C-PE3 when those prefixes are authorized to 
be reached by those edge nodes.





822                                   +-------+

823                                   |Payment|

824                          +------->|  GW   |<----+

825                         /         +-------+      \

826                        /        Blue Tunnel       \

827                       /for Payment App:192.0.2.9/30\

828                      /                              \

829              +------+--+                        +----+----+

830            --|         |                        |         |-192.0.2.9/30

831              |         |     Red Tunnels        |         |

832            --| C-PE1   |------------------------|         |-192.0.2.4/30

833              |192.0.2.1|                        |  C-PE2  |

834            --|         |------------------------|192.0.2.2|-192.0.2.8/30

835              |   ------+                       +|         |   VLAN=25;

836                                               / |         |-192.0.2.10/30

837              +---------+                     /  +---------+

838            --|         |--------------------+

839              | C-PE3   |                   /

840              |192.0.2.3|                  /

841            --|         |-----------------+

842              +---------+

843            Figure 7: Flow Based SD-WAN Segmentation



GV> What are Red Tunnels and Blue tunnels? Could it be that during the editing 
of the section some context was lost on the tunnel descriptions.

[Linda] Added this sentence at the end of the Figure 7:

In Figure 7, the “Blue Tunnel” denotes the tunnel used exclusively for Payment 
Application traffic toward the Payment Gateway, whereas the “Red Tunnels” 
denote tunnels used for other authorized traffic among SD-WAN edge nodes.





869      SD-WAN services to clients can be IP-based or Ethernet-based. For

870      IP-based services, an SD-WAN edge can learn client addresses from

871      the client-facing interfaces via OSPF, RIP, BGP, or static

872      configuration. For Layer-2 services, the EVPN parameters, such as



GV> Can references to the base specs of these protocols be added?

[Linda] Added the reference:

SD-WAN services to clients can be IP-based or Ethernet-based. For IP-based 
services, an SD-WAN edge can learn client addresses from the client-facing 
interfaces via OSPF [RFC2328][RFC5340], RIP [RFC1058][RFC2453], BGP [RFC4271], 
or static configuration. For Layer-2 services, the EVPN parameters, such as



1041     this Case, an outer UDP field is added to the encrypted payload



GV> s/Case/case/

[Linda] Changed.



Kind Regards,

Gunter Van de Velde

Routing Area Director




_______________________________________________
BESS mailing list -- [email protected]
To unsubscribe send an email to [email protected]

Reply via email to