Transit Control Plan requirement - need some help!!

[Beacon Bits]

I have a new site is being built where I have around 20-30 users with wireless requirement.

I have decided to use "Fabric in a Box"(FiB) using Cat9300.

As I understood that FiB is Border, Control Plan, Edge and Wireless in the same box but I'm confused about the Transit Control plan. Would the same box FiB also be a Transit Control Plan as well??

Or do I need any Transit Control Plan device in our main Fabric site or how the FiB Transit CP works (if it exist)?

Can someone please share anything about Transit Control Plan requirement where it is must be used?

I have gone through the CiscoLive session but explanation is not clear as if it is must?

Cisco SD-Access - Connecting Multiple Sites in a Single Fabric Domain - BRKCRS-2815

On-Demand Library - Cisco Live Global Events - Cisco

regards,

B

[jalejand]

Transit CPs can't be any other thing that MS/MR (Control Planes). These can't be borders or edges already, you'll need an standalone device.

Regards

[KevinR99]

See below

[Jonathan Cuthbert]

The Transit Control Plane Node is a dedicated device that is used with an SD-Access Transit.

If your Fabric in a Box site is connected to an SD-Access transit, you will need to assigned devices to operate in the Transit Control Plane Node role.  Please note: the Transit Control Plane Node is a DEDICATED device.  You cannot colocate it with any other function or role.

For more details including design, please see:

https://www.cisco.com/c/en/us/td/docs/solutions/CVD/Campus/cisco-sda-design-guide.html#Transit_Control_Plane_Node

https://www.cisco.com/c/en/us/td/docs/solutions/CVD/Campus/cisco-sda-design-guide.html#DistributedControlPlaneNodeandBorderNode

https://www.cisco.com/c/en/us/td/docs/solutions/CVD/Campus/cisco-sda-design-guide.html#CSR1000vasControlPlaneNode

[Beacon Bits]

Thanks you both for the reply @jalejand and @Jonathan Cuthbert.

I have gone through this CVD before but it does not say that it is necessary for the deployment.

Can my one fabric site connect to the other Fabric site or FiB without introducing the Transit CP?

The logic of the Transit CP is very clear that it keeps aggregated summary routes for all the sites. But is it must or not??

Can I connect my both site without Transit CP?

Let say I don't have Transit CP what would be the impact and if I do then what benefit would I have other than it keeps the Aggregate routes.

[KevinR99]

I know the TCN's can be deployed in any location reachable via the underlay.  Is there any compelling reason not to deplo then on a stacked edge?  This is out cheapest option with regards to connectivity.  We could simply use 2 x copper connections spread across an Edge stack's switches.  The TCN's don't have a significant load placed on them so it woud seem overkill to waste high bandwidth ports and transceivers.

Thanks, Kev.