1. Konstantin agouros Omkar deshpande
Implementing Carrier Services in OpenFlow - OpenFlow Switch as MPLS PE - Router
Konstantin agouros
Omkar deshpande

2. Agenda SDN Overview- OpenDaylight, OpenFlow, Open vSwitch MPLS
Southbound plugins for OpenDaylight - BGP-LS, PCEP
Segment Routing (SPRING)
Network Setup
Proof-Of-Concept
Conclusion

3. Software Defined Networking
Northbound APIs
Controller (OpenDaylight, ONOS, Floodlight, RYU, etc.)
Southbound APIs
OpenFlow
Open vSwitch
Mininet
Source:

4. Source: www.opennetworking.org
OpenFlow
Version 1.5.1
OpenFlow Switch
Match fields
E.g switch port, IP source & destination, VLAN ID, MPLS , MAC address
Instructions
Apply-Actions, Clear-Actions, Goto-Table
Actions
E.g output port_no. , PUSH, POP - MPLS, VLAN, drop etc.
Counters
Source:

5. Source: www.opendaylight.org

6. MPLS IP forwarding based on label, not on IP header
FEC is encoded as a Label
Label Switched Path
MPLS forwarding - Hop by hop, Explicit routing
BGP/MPLS L3 VPN
MPLS Protocols
LDP – Relies on IGP, best effort LSP, No TE
RSVP-TE – TE, Soft state, Fast Re-Route,
EROs
RSVP
LDP

7. PCEP Communication protocol between PCC and PCE
Works in sync with RSVP
TCP based protocol- port 4189 at PCE side
Used for LSP computation
PCE Initiated
PCC Initiated
Installation
feature:install odl-bgpcep-pcep-all

8. BGP-LS Limitations of IGP Share Link-State or TED with controller
Lacks view of complete topology
No end-to-end LSP across multiple domains
Share Link-State or TED with controller
Carries link, node, and prefix properties and attributes, such as the link and prefix metric or auxiliary Router-IDs of nodes
Install: feature:install odl-bgpcep-bgp- all

9. Segment Routing Source Packet Routing Networking (SPRING)
Implemented by IGP
Advertise MPLS labels in IS-IS TLVs or OSPF LSAs
No BW reservation on ist own but possible with PCEP
Global Segments
Local Segments
How does it work ?

10. Segment Routing: How does it work ?
L3,L4
L1-MPLS: P2 node
L2-MPLS: P2-P3 Adj SID 1000
L3-MPLS: PE2 –
L4- MPLS: Service SID
Payload P3
1000
Label Range: to
L2, L3, L4 L4
PE2
PE P P2 P4
2000

11. Network Setup

12. Proof-Of-Concept 1: RSVP-TE with PCEP
Using PCEP with RSVP-TE
Computes LSP externally from the controller and can be
verified on the router - PCE_STATE_UP
Not compatible with OpenFlow network
OVS cannot be a PCC : No end-to-end LSP
Concept of Static LSP + PCE computed LSP works
With LDP but not with RSVP
PE1 refuses packets from OVS (acting as PE) with
MPLS labels
Only router to router LSP (PE1  PE2)
Solution: Segment Routing

13. Proof-Of-Concept 2: Segment Routing
Uses IGP to distribute Node , Adj Segments
No need of RSVP or LDP
Check IS-IS database and PUSH 3 labels /segments with OpenFlow
Two transport and one L3 VPN service Label
Router accepts this time, as router is aware of Global segment prefix
(800040) belongs to PE2
OVS behaves as a PE in this case and actual router PE1 becomes LSR
along with other routers in MPLS core
Static LSP on both sides of PEs

14. Mechanism and Results L1, L2, L3 REMOVED 800040,1000123,1000125

15. Conclusion BGP Link-State extensions for Segment Routing
Successful integration of OpenFlow with classical network
Limitations
Integrating OpenFlow with RSVP
BGP-LS does not include SPRING Information but possible according to IETF draft BGP Link-State extensions for Segment Routing
Junos version 16.1R2.11- No support for SPRING LSP from PCE
SPRING may include a stack of more than 3 labels , not possible with current version of OpenFlow 1.5.1

16. THANK YOU
Questions ?