Switching and Routing projects description

Transcription

1 Switching and Routing projects description

2 Outline Introduction to OpenFlow A case study The projects Additional information

3 What s OpenFlow An open standard, which defines: An abstraction of ethernet switches forwarding plane, by means of flow tables description A protocol for interfacing with an external controller, to add/remove flow entries and get statistics A first step toward Software Defined Networking (SDN): abstraction of networks control plane Development started at Stanford University, transferred to Open Networking Foundation (ONF) in March 2011

4 OpenFlow switching OpenFlow Switch specification OpenFlow Ethernet Switch Controller PC sw Secure Channel hw Flow Table Add/delete flow entries Encapsulated packets Controller discovery N. McKeown, OpenFlow (Or: Why can t I innovate in my wiring closet? ),

5 Forwarding Plane Abstraction Flow table entries Rule Ac=on Stats Packet + byte counters 1. Forward packet to port(s) 2. Encapsulate and forward to controller 3. Drop packet 4. Send to normal processing pipeline 5. Modify Fields Switch Port VLAN ID MAC src MAC dst Eth type IP Src IP Dst IP Prot TCP sport TCP dport + mask what fields to match

6 OpenFlow protocol Support three message types: Controller-to-switch messages Configuring the switch Exchanging switch capabilities Managing the Flow table Symmetric messages Send in either direction Diagnose problems in switch controller connection Asynchronous messages From switch to the controller Announce change in network state, switch state etc.

7 OpenFlow controller Openflow controller is a centralized entity for the entire OpenFlow network NOX is an (one of many) open source OpenFlow controller simplified platform for writing network control software in C++/Python M. Meulle, W. Daar, Introduction to OpenFlow, CORE-TPN-RIV, 23 Jul. 2010

8 OpenFlow for SR Projects: You will be mainly asked to: Program the behavior of very simple networks Only the controller must be programmed The switch is given, and fixed Work on software-emulated networks Hosts, Switches, controllers are all virtualized on your PC Two emulation softwares: Mininet and Netkit Perform acceptance tests (optionally performance tests) iperf, hping(3), wireshark, others

9 Recommended references Open Networking Foundation: (new official site) OpenFlow official site: (old site, but has interesting material) OpenFlow white paper: (very introductive primer) OpenFlow Tutorial with Mininet: (we suggest this to start learning OpenFlow) OpenFlow technical specification: (you must refer to this version) Nox official site: (to write your OpenFlow controller software in C++) Mininet official site: (a software to emulate a network in your PC) Netkit official site: (another software to emulate a network in your PC)

10 Outline Introduction to OpenFlow A case study The projects Additional information

11 (Hybrid) Wireless-Optical Broadband Access Network (WOBAN) OLT METRO/CORE NETWORK

12 Why WOBAN? Gateway ONU ONU OLT Gateway Potential advantages over existing access networks: - Cost effectiveness (less deployment and maintainance costs) - Broadband access - Ubiquitous access (because of wireless front-end) - Redundant routes offered by wireless front-end - Redundant capacity offered by optical backhaul Energy saving?

13 How to pursue energy saving? When the traffic load is low, put some ONU (and corresponding Gateway) nodes in sleep state, i.e. they switch off their transceivers and enter a low power consumption state Gateway ONU ONU OLT Gateway Sleeping nodes become unreachable by the rest of the network, BUT full connectivity is still guaranteed, provided that: - Wireless mesh re-routes upstream traffic to active gateways - OLT re-routes downstream traffic to active ONUs

14 Simplified WOBAN case study ONU 1 User 1 Router 1 Gateway 1 OLT ONU 2 User 2 Router 2 Gateway 2 Assumptions: - 2 bidirectional traffic flows (User 1 OLT; User 2 OLT) - Users cannot associate directly to Gateways - Static association between Users and their access Routers (no handovers) - Each ONU connects to exactly one Gateway - Ad-hoc dynamic routing for wireless mesh part - Static routing in the wired part

15 Equivalent test-bed ONU 1 User 1 Router 1 Gateway 1 PC + WiFi card PC + WiFi +Ethernet card OLT User 2 Router 2 Gateway 2 ONU 2 PC + Ethernet card PC + WiFi card PC + WiFi +Ethernet card - WiFi (IEEE g/n) in ad-hoc mode for wireless mesh part - Ethernet for wired part - Emulation of nodes by means of PCs with Linux OS

16 Outline Introduction to OpenFlow A case study The projects Additional information

17 Projects 12-1 & 12-2 Test case ONU 1 User 1 Router 1 Gateway 1 PC + WiFi card PC + WiFi +Ethernet card OLT User 2 Router 2 Gateway 2 ONU 2 PC + Ethernet card PC + WiFi card PC + WiFi +Ethernet card - Traffic flows between each user and the OLT - ONU 2 and Gateway 2 enter sleep state WiFi and Eth cards are disabled - Have traffic flows been properly re-routed?

18 Project 12-1: Test-bed in OpenFlow 1. Implement the test-bed in an emulated network scenario: Network emulation via Mininet OpenFlow control (controller resides in the OLT) Proactive routing tables 2. Once the test-bed is ready, let ONU 2 and Gateway 2 enter into sleep state and verify that re-routing is effective 3. Perform tests: iperf, hping(3), video (optionally) 4. Replicate scenario and tests in a real Bonsai Lab

19 Project 12-2: Test-bed with Ad-hoc Routing 1. Implement the test-bed in an emulated network scenario: Network emulation via Netkit Ad-hoc routing protocol (OLSR or AODV) in the wireless mesh part, static in the wired part 2. Once the test-bed is ready, let ONU 2 and Gateway 2 enter into sleep state and verify that re-routing is effective 3. Perform tests: iperf, hping(3), video (optionally) 4. Replicate scenario and tests in a real Bonsai Lab

20 Project 12-3: Traffic Policing 1. Measure the traffic amount (every T seconds) for each input flow in an OpenFlow controlled switch; 2. Perform a simple traffic policing over each input flow, i.e.: if current traffic amount is lower than a threshold, then forward the packet; otherwise drop the packet 3. Perform tests: iperf, hping(3) 4. Replicate scenario and tests in a real Bonsai Lab

21 Project 12-4: Traffic Re-routing 1. Set up an OpenFlow controlled network composed by 5 elements Same topology of the test-bed, all-wired Controller installed in the OLT 2. Change the routing of user data traffic and verify it Reactive update of routing tables Switch-Controller traffic should not be re-routed 3. Perform tests: iperf, hping(3) 4. Replicate scenario and tests in a real Bonsai Lab

22 Project 12-5: VLAN Implementation 1. Implement a VLAN (IEEE 802.1Q) switch with OpenFlow The switch ports are divided into port groups each belonging to a single VLAN Configure a port as trunk port, over which all tagged frames are sent and received 2. Properly manage both incoming and outgoing tagged frames 3. Perform tests: iperf, hping(3) (e.g. consider 2 switches connected by a single trunk link) 4. Replicate scenario and tests in a real Bonsai Lab

23 Project 12-6: Setup and Performance of a Content-Centric Network The CCNx project ( is defining a novel way of addressing Internet contents, which is based on the request of contents names, instead of server addresses. The proposed project consists in: Set-up and testing a CCNx implementation in an experimental network (at first an emulated network, then a real Bonsai lab) Performance measurements (end-to-end delay), for increasing number of nodes of a simple application

24 Project 12-7: Elastic-rate Flexi-grid Core networks 60 Gbit/s WDM occupied (but unused!) f Elastic Rate Flexi-grid 6 minigrids (5GHz each) f 100 Gbit/s txp à 50 GHz (including g.b.) 1. Scenario Event-driven dynamictraffic simulator Core mesh network Flexible grid (no WDM) Adaptive-rate txp à 40 GHz (30+10 g.b.) 2. Target(s) Insert multi-criteria resource allocation (now only first-fit spectrum allocation) different traffic distribution (e.g., bursty traffic)

25 Project 12-8: Optical Metro rings with Flexi-grid 1. Scenario Event-driven dynamic-traffic simulator Optical metro ring Flexible grid (no WDM) Multi-criteria Routing and Spectrum Allocation (RSA) 2. Target(s) Insert different traffic distribution (e.g., bursty traffic) Parametrization of the simulator (nr of nodes/links, wavelengths, transponders used )

26 Project 12-9: Lambda-switched shuffle-exchange Y Z AWG Wavelength converter Multistage implementation Folded implementation Linecard

27 Project 12-9: Lambda-switched shuffle-exchange 1. Scenario Clock-driven frame-traffic simulator (upgrading an existing simulation tool) Board-to-board interconnection Shuffle-exchange routing algortithms 2. Target(s) Power consumption / delay measurements Multistage vs. folded implementation comparison

28 Additional information Final outcome of the projects: 1. Write a report 2. Create the project documentation (commented code, etc.) 3. Prepare a presentation We will organize a final project day in the Bonsai Lab to enjoy your presentations J Contacts: Nicola Carapellese (tutor): carapellese@elet.polimi.it