1. Draft-nalawade-kapoor-tunnel-safi 03.txt
Simon Barber

2. What is the tunnel-safi Draft
Drafts proposes to allow tunnel endpoint discovery and encapsulation/ attribute propagation using a new MP-BGP SAFI that will allow its propagation over V4 or V6
Works within and across Autonomous Systems
Draft is currently active in IAG L3VPN

3. Tunnel-safi draft cont..
Draft is based around each egress system advertising its available endpoints and their attributes.
This information is been propagated to all MP-BGP speakers configured for tunnel-safi.
For reduce MP-BGP peerings a route reflector can be deployed.

4. Typlical Deployment of tunnel-safi
Route Reflector
Tunnel E/P
Tunnel E/P
Tunnel E/P
BGP Tunnel-Safi

5. Format of Tunnel-SAFI AFI-1, SAFI = 64 for IPv4 Tunnel AFI
Format is
NLRI – Identifiers the endpoints network address
Tunnel- Method(s) List of one or more TLVs
Defined types L2TPv3, GRE, IPSEC, MPLS, L2TPv3 in IPSec, GRE in IPsec.

6. GRE TLV 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 =======================
=======================
|T| TYPE = |
Length (2 Octets) |
Preferences (2 Octets) | Indicating the sender( Egresses)
======================= Preference of this type of tunnel EP
|S|K| FLAGS |Reserved | S = Sequencing, k = key
GRE key (4 Octets) |

7. L2TPv3 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 =======================
=======================
|T| TYPE = |
|Length (2 Octets) |
|Preferences (2 Octets) | Indicating the sender( Egresses)
| | Preference for this type of tunnel.
|S|FLAGS |Cooke Len |
|Session ID (4 Octets) |
====================== |
|Cookie (vairiable) |

8. MPLS TLV 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 =======================
=======================
|T| Type = 0x |
| Length (2 octets) |
======================
| Preference (2 octets) |
| Flags |

9. Advertising the TLVs Route Reflector Tunnel E/P Tunnel E/P Tunnel E/P
MGRE,L2TPv3
Tunnel E/P
L2TPv3
Tunnel E/P
MGRE

10. Applications
L3VPN
Tunnel SAFI is used to propagate Tunnel endpoints and encapsulation information.
2547bis is used to exchange VPN routing information and Labels.
Information from tunnel Safi is combined with VPN NLRI information to appropriate tunnel point.
Layer2 IPvX Tunnel Encap Label Payload
Solution is deployed.

11. Some Applications…. L3VN using 2547bis
Route Reflector
Tunnel E/P
L2TPv3
Tunnel E/P
L2TPv3
Tunnel E/P
L2TPV3
PEs running tunnel SAFI and 2547bis

12. Full Mesh Ovelay GRE Tunnels
Using the Tunnel Safi to advertise GRE endpoints it is possible for each participant to dynamically create point to point overlay GRE tunnels to every other participant it receives a tunnel SAFI from
Same applies to IPSec tunnels.

13. Full Mesh Overlay GRE tunnels
Tunnel E/P
Tunnel E/P
Tunnel E/P

14. Whats Missing
Currently Multiploint Overlay tunnels can not be supported because of the lay of an overlay to transport address resolution mechanism.
Nothing stopping this being added to tunnel- safi

15. Thank You

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