Yao,
BGP-LS was designed to solve also the distribution of link-state information
between BGP speakers (see Figure 1 from RFC 7752 below).
Just ask yourself: why would one want to use a point to multipoint state
replication protocol as complex as BGP for *just* client server alike
replication ?
We wanted from day-1 to leverage the graph independent replication abilities of
BGP - so doing inter BGP-LS graphs is a legit use-case.
HTH,
/hannes
---
The collection of link-state and TE information and its distribution
to consumers is shown in the following figure.
+-----------+
| Consumer |
+-----------+
^
|
+-----------+
| BGP | +-----------+
| Speaker | | Consumer |
+-----------+ +-----------+
^ ^ ^ ^
| | | |
+---------------+ | +-------------------+ |
| | | |
+-----------+ +-----------+ +-----------+
| BGP | | BGP | | BGP |
| Speaker | | Speaker | . . . | Speaker |
+-----------+ +-----------+ +-----------+
^ ^ ^
| | |
IGP IGP IGP
Figure 1: Collection of Link-State and TE Information
---
> On 29.07.2020, at 03:57, [email protected] wrote:
>
> Hi Acee,
>
> Thanks for reading the draft.
>
> Yes, the main purpose of this draft is to carry the segment segment
> information via IGP so only one node per AS need to be connected with the
> controller through BGP-LS.
>
> With the existing BGP-LS extension draft, it is certainly one solution to
> configure BGP sessions between all the service function nodes and controller,
> and each node sends the SF information to the controller individually.
>
> And if I get you right, we can also select one node to have a BGP session
> with the controller and configure BGP sessions between the selected node and
> SF nodes.
>
> But how the selected node get the SF information from SF nodes via BGP needs
> to be solved, since BGP-LS is typically used for exchanging information
> between the south and north rather than nodes of the same level, and there's
> no other existing BGP extension for distribute SIDs information between nodes
> .
>
> This draft aims to provide an alternate way if the operators prefer running
> IGP on SF nodes.
>
> So we would like to collect comments on the WG session to see how others
> think about it.
>
>
>
> Regards,
>
> Yao
>
>
>
>
>
>
>
> 原始邮件
> 发件人：AceeLindem(acee) <[email protected]>
> 收件人：刘尧00165286;[email protected] <[email protected]>;
> 抄送人：[email protected] <[email protected]>;
> 日 期 ：2020年07月29日 01:53
> 主 题 ："IGP Extensions for Segment Routing Service Segment"
> -draft-lz-lsr-igp-sr-service-segments-02
> Speaking as WG member:
>
>
>
> It seems the sole purpose of this draft is to get service segment information
> from nodes in the IGP domain to the IGP node that has a BGP session with the
> controller. You don’t need to put this information into the IGP in order to
> do this. Simply configure BGP sessions for the BGP-LS AF between the nodes
> with service functions and the node selected to have a BGP session with the
> controller.
>
>
>
> Speaking as WG Chair – please let me know if we can omit this draft from the
> agenda.
>
>
>
> Thanks,
>
> Acee
>
>
>
> _______________________________________________
> Lsr mailing list
> [email protected]
> https://www.ietf.org/mailman/listinfo/lsr
_______________________________________________
Lsr mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/lsr
