基 於 SDN 與 可 程 式 化 硬 體 架 構 之 雲 端 網 路 系 統 交 換 器

Transcription

1 基 於 SDN 與 可 程 式 化 硬 體 架 構 之 雲 端 網 路 系 統 交 換 器 楊 竹 星 教 授 國 立 成 功 大 學 電 機 工 程 學 系

2 Outline Introduction OpenFlow NetFPGA OpenFlow Switch on NetFPGA Development Cases Conclusion 2

3 Introduction With the proposal of OpenFlow by Stanford, the concept of SDN is all the rage. SDN breaks the traditional designs and makes more possibilities on network. Through development in hardware, we can provide more support to software that takes control of network. 3

4 Characteristics of Cloud Computing Elastic and infinite resources Abstracted/Pooled resources Pay-per-use, Scale up or down On demand, Self-Service Multi-tenancy Multiple independent users Security and resource isolation Amortize the cost of the (shared) infrastructure Flexibility service management Resiliency: isolate failure of servers and storage Workload movement: move work to other locations

5 Typical Data Center Network Aggregation Switch ToR Switch vswitch VM VM Aggregation Switch ToR Switch vswitch VM VM Aggregation Switch ToR Switch vswitch VM VM Mix of bare metal and virtualized servers Mix of physical and Virtual switches Multilevel - access, aggregation, core vswitch VM VM vswitch VM VM Physical Server Multiple datacenters connected via L3 vswitch VM VM vswitch VM VM Physical Server

6 Requirements for Cloud Networking Cloud Networking technology should meet the requirements: Transparent VM migration (high agility) Easy deployment requiring less human administration Efficient Loop-free forwarding Fault Tolerance High Scalability Current DCN technology are struggling to meet the requirements. Layer 3 protocol can not support the transparent VM migration. Current Layer 2 protocol is not scalable due to the size of forwarding table and native broadcasting for address resolution.

7 Software Defined Network SDN is part of a long history of efforts to make computer networks more programmable. More manageable enable innovation in network design, and lower the barrier to deploying new services. Key Concepts separating the control (policy) plane from the data (forwarding) plane, providing well-defined forwarding abstractions (e.g., pipeline of flow tables) with standard programmatic interfaces (e.g., OpenFlow), and exposing high level abstractions to implement a wide-range of network policies and new network technologies.

8 OpenFlow

9 What is OpenFlow? OpenFlow is an open standard to deploy innovative protocols in production networks. OpenFlow provides an opened protocol to program the flow table in different switches and routers. Researchers can control flows by their own. OpenFlow is currently being implemented by major vendors. 9

10 What is OpenFlow? (conf.) 10

11 How does the OpenFlow work? Flow Table, with an action associated with each flow entry, to tell the switch how to process the flow Secure Channel connects the switch to a remote control process (called the controller), allowing commands and packets to be sent between a controller and the switch using The OpenFlow Protocol, which provides an open and standard way for a controller to communicate with a switch. SW HW OpenFlow Switch Secure Channel Flow Table OpenFlow Protocol SSL PC Controller 11

12 OF Protocol Communication Process Packet in OpenFlow Switch Miss! packet in controller flood 1. There is no matched information in table packet out packet in 2. There is matched information in table Flow Mod 12

13 OpenFlow-enabled Network Optimizing Control Plane the Fabric 1. Multi-path inter-connection 2. Higher bandwidth links 3. Higher packets processing rates 4. Slicing and virtualized the network Network topology, ACLs, Forwarding and Routing table maintain, control messages and routing calculation, QoS, Link Management Each network devices has its own control plane and data plane. Network Services APIs Multipath, Security etc. Data Plane Link, Switching, Forwarding, Routing

14 NetFPGA

15 NetFPGA There are many commercial switches with SDN enabled function now. Cisco, Extreme, HP, Juniper, NEC, Pica8, Pronto Consideration for academic development: Hardware design modification Ability of co-design with SDN Controller Price NetFPGA is a good choice. 15

16 NetFPGA Introduction NetFPGA Proposed by Stanford University in Reconfigurable hardware platform optimized for high-speed network. SATA Interface Gigabit Ethernet Interface Xilinx Virtex-II Pro 50 DRAM Broadcom Ethernet Transceiver PCI Interface SRAM Xilinx Spartan II 16

17 NetFPGA Components 17

18 OpenFlow Switch on NetFPGA

19 Hardware Modules 19

20 Header Parser Extract the header from incoming packets Re-format to 240-bit data and send them to the next stage 20

21 Exact Match Lookup Match each field exactly in a flow Implement using off-chip SRAM Provide flow entries Search flow entries with hash functions 21

22 Wildcard Match Lookup Match certain fields in a flow Allow don t care fields Implement using on-chip TCAM Provide 32 flow entries 22

23 Arbiter Use to determine query results from Exact Match Lookup or Wildcard Lookup module Give Exact/Wildcard module feedback for updating counters Wildcard Match Exact Match hit miss hit exact wildcard miss exact drop 23

24 Packet Editor Get a packet from the buffer Add a header with destination interface(s) according to lookup results Send the packet to the interface(s) 24

25 Development Case 1 VLAN-Tag Translation

26 System Architecture Enable the VLAN assignments inside the OpenFlow networks POX Controller VLAN Translation Mechanism 1. Provide a control API to conjunct with applications or services 2. Program the edge OF switch to transmit the tagged-traffic across OF networks 3. Dynamic learning the host location across OF networks with the same VLAN ID 26

27 Implementation Designing Blocks in POX Controller Parse Daemon Translation the info into table entries. Translation Port Outside VLAN ID Allocated VLAN ID Host Information Internal Forwarding Layer 2 learning For inside traffic communications VLAN Forwarding Two tables For OF networks WAN And WAN OF networks 27

28 Flow Installation by POX Controller Translation Port Outside VLAN ID Allocated VLAN ID Host Information Flow Table in OF Switch A Wildcard tuple match action1 action2 Flow Table in OF Switch B Wildcard tuple match action1 action2 packet.vlan.id Modify vlan.id Enqueue/ output packet.dst.mac Modify vlan.id output 28

29 Use Case Importing the Xen architecture as the application with VLAN translation mechanism in the edge OpenFlow switch for connecting testbeds. 29

30 Development Case 2 A Traffic Management Module

31 Introduction SDN enables flexible forwarding controls on different flows. However, while several connections share the path, resource competitions occur and disturb each other. Deploy traffic management policies 31

32 Design Overview 32

33 Input Arbiter Design Architecture SRAM DRAM traffic management module User Data Path Header Parser Exact Match Lookup Wildcard Lookup Arbiter Packet Editor MAC TxQ CPU TxQ MAC TxQ CPU TxQ MAC TxQ CPU TxQ MAC TxQ OpenFlow Output Port Lookup Output Queues CPU TxQ 33

34 Design Architecture (cont.) done 34

35 Design Architecture (cont.) Fill in unused 8 bits for the new action priority queue setup Header Fields Counters Actions set_dl_src 63~48 set_vlan_pcp set_dl_dst 47~32 set_vlan_vid 31~16 action_flag 加 入 輸 出 速 度 佇 列 編 號 set_dl_src Output Speed Queue Num. 15~0 forward_bitm ask set_nw_dst set_nw_src set_dl_dst set_tp_dst set_tp_src set_nw_tos set_nw_dst no use

36 Evaluation Scenario 36

37 Evaluation (cont.) Byte Count TCP cross traffic 1058byte/packet Sending in 42Mbs VoIP traffic Cross traffic Time (ms) Byte Count TCP cross traffic 1058byte/packet Sending in 387Mbs Video traffic Cross traffic Time (ms) 37

38 Conclusion

39 Conclusion VLAN Tag Translation mechanism Traffic management mechanism Control Framework 39

40 Q & A 40

41 Thank you! 41