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Improvement of Content Server with Contents Anycasting Using OpenFlow. Othman Othman M.M. , Koji Okamura Kyushu University. Outline:. Goal . Current Technologies. Limitations of Current Technologies. Advantages of Combining Technologies. How to Combine Technologies. Anycast Scenario
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Improvement of Content Server with Contents Anycasting Using OpenFlow Othman Othman M.M. , Koji Okamura Kyushu University
Outline: • Goal . • Current Technologies. • Limitations of Current Technologies. • Advantages of Combining Technologies. • How to Combine Technologies. • Anycast Scenario • BitTorrent (P2P) Scenario. • Usage Scenario. • OpenFlow Overview. • Requesting Content. • Implementation. • Conclusion.
1-Goal: • To have contents with high availability. • Improving the availability of the content server. • To improve the overall usage of bandwidth of the whole network.
2-Current Technologies: • Peer to Peer: • Depends on user clients to provide service. • Implements an application layer overlay network. • Overlays used to for indexing and peer discovery. • Anycast: • Multiple nodes with the same anycast address (Sa). • Packet sent to (Sa) will be delivered to the node with nearest location according to the routing table. Sa Sa Sa Fig 1. Anycast Fig 2. BitTorrent Source :http://en.wikipedia.org/wiki/Image:Torrentcomp_small.gif
3-Limitations of Current Technologies: • Peer to Peer: • Overhead because of overlay nature, protocol, peer discovery, and looking up in index. • Service depends on user’s contribution. • Anycast: • All of the content servers must have identical contents. • Lacks the flexibility, and not dynamic. 10.10.10.1 192.168.0.1 Cont 1 Cont 1 Cont 2 Cont 2 Router 1 Cont 3 Cont 3 Router 2 Fig 2. BitTorrent Source : http://computer.howstuffworks.com/bittorrent2.htm Cont n Cont n 10.10.10.1 Router 3 Router 4 192.168.0.2 Destination Next-Hop Distance 192.168.0.0 127.0.0.1 0 10.0.0.1 192.168.0.1 1 10.0.0.1 192.168.0.2 2
4-Advantages of Combining Technologies: • Advantages of Peer to Peer: • High availability of popular contents, due to users’ contribution in providing service. • Advantages of Anycast: • Fast and does not require any effort of the users, because choosing destination (decision making) is done in the network. • Content Centric Network: • Treats contents as a primitive not the connection. • Combination of those technologies: • Choosing destination by network: to remove the burden of finding destination and thus a faster response. • Users contributing in service: to improve the availability, and improves the overall use of bandwidth in whole network (reduce bandwidth used by server). • Content ID: to have more flexibility down to the level of contents rather than the node level.
4-Advantages of Combining Technologies: • Anycast. • Content Centric Networks. • Peer to Peer. • Combination of those technologies: • Users contributing in service: to improve the availability, and improves the overall use of bandwidth in whole network (reduce bandwidth used by server). • Choosing destination by network: to remove the burden of finding destination and thus a faster response. • Content ID: to have more flexibility down to the level of contents rather than the node level. AnycastManager Content Server Su Client A Client B Content ID = X To: Au Cont id=X Au Bu Get Content ID? To: Su Cont id=X
5-How to Combine Technologies: • We have designed the “Content Anycasting” that combines different technologies strength points as shown in the previous slide. • Content anycasting manages to do its rule by using: • OpenFlow for the process of choosing the destination, along with the aid of the content server. • A new procedure for requesting content is introduced to enable the clients to get the contents.
6-Anycast Scenario: 10.10.10.1 10.10.10.1 Client will send packet to 10.10.10..1 10.10.10.1 Cont 1 Cont 1 Cont 1 Cont 2 Cont 2 Cont 2 Network will choose end node based on routing measures Cont 3 Cont 3 Cont 3 10.10.10.1 Cont n Cont n Cont n
7-BitTorrent (P2P) Scenario: Tracker 100% Seeder 70% 30% 100% Seeder 0%
8- Usage Scenario: Anycast Manager 1 Content Server if Destination IP: 10.10.10.1 & Content id: 12345 Change : Destination IP: 192.168.10.1 2 3 10.10.10.1 Client A Client B 192.168.10.1 192.168.20.1
8- Usage Scenario: This figure shows the first phase of the content request. • Step 1: client B requests the content id. • Step 2: server sends the content id to the client B. Anycast Manager 10.10.10.1 Content Server 1 192.168.20.1 192.168.10.1 Client A Client B 2 Content id: 12345
8- Usage Scenario: Destination IP: 10.10.10.1 Content id: 12345 10.10.10.1 Anycast Manager Content Server 2 Destination IP: 192.168.10.1 Content id: 12345 1 Client B Client A 3 192.168.20.1 192.168.10.1
9- OpenFlow Overview: • Separates routing decision making (in controller) and the forwarding (in the switch or router). • Matching in the switch or router is done according to Layer 2, 3 and VLAN headers. Figure 1: OpenFlow switch (ref: Nick McKeown et al, “OpenFlow: enabling innovation in campus networks”)
9- OpenFlow Overview: • OpenFlow relies on the Flow-table, which is contains: • Header fields are the ones the incoming packet is matched against: • The actions can be : forwarding the packet to physical port, enqueue the packet in a physical port’s queue, dropping the packet or modifying incoming packet’s header fields Figure 1 Figure 2
10- Requesting Content: Two phases: • Phase 1: • Client browses to find desired content. • Client sends the request (e.g. HTTP GET) • Server responds with content ID, to be sued in phase 2 to get the file. • Phase 2: • Uses 3 way handshake. • Requires modification to the TCP.
10- Requesting Content: • Phase 2: 3 way handshake: • Start with SYN packet that is sent to the server. • Using OpenFlow and the content id packet will be redirected to an other client (Current Client). • Current client acknowledge to the SYN with its IP in packet. • New client starts to use the Current client’s IP address in the session. OpenFlow router New Client Current Client Destination: serverIP :SYN Destination: CurrentClientIP :SYN SYN/ACK With CurrentClientIP Destination: CurrentClientIP :SYN
11- Implementation: • Currently we are building redirection system, modified content server, modified clients and using the reference OpenFlow implementation. • First, Redirection system with one Anycast manager. • Second, duplicate redirection systems each with its own Anycast manager. • Aiming to measure: communication cost, response time, efficiency in different load patterns and others. • And comparing those values to other solutions like the anycast and peer to peer.
12- Conclusion: • Content anycasting aims to combine the strength points of different technologies like the anycast, peer to peer and content centric networks . • The goal is to improve the content server by increasing its serving capacity, with less overhead and more efficient usage of the bandwidth in the whole network. • In a way that overcomes the limitations of those technologies.
13- Q&A: • Thank you for listening.
4- System Overview:Anycast Manager: • Functionality: • Receive the redirection request form the content server. • If the redirections are in the same AS make redirections and send them to the OpenFlow routers or switches. • And if in different AS send the redirection request to the appropriate anycast manager. Receive redirection request Lookup AS numbers for each current user client’s IP address in the redirection request Generate copies of the redirection request each designated for one AS Is the copy for this AS Yes No Send it to the Anycast manager of the AS to which this copy is designated to Process it by the Redirection controller
1- Introduction: • Internet plays many roles, one of them is delivering content. • Relying mainly on the Client / Server model and Peer to Peer models. • Divers contents: audio, video, large files. • Number of users increases. • Bandwidth for users increases. • Traffic increases by a factor of 1.7 / year.
2- Motivation: • This created a kind of imbalance: • Number of client increases. • Also the bandwidth for the clients increases. • Client side have more and more demands. • Servers have to implement solutions to keep up with this increase. • More efforts on the server side. diverse content diverse content more bandwidth more bandwidth more clients more clients Server Clients Server Clients
8- Usage Scenario: This figure shows the initiation of the redirection : • Step 1: the server sends the redirection request, which includes the contents ids and the IP addresses of the clients downloading those files along with their uploading capabilities. • Step 2: the Anycast manager makes the OpenFlow redirections and sends them to the OpenFlow switch or router. • Step 3: OpenFlow switch or router stores the redirections.
7- System Overview: • Content Server. • Anycast Manager. • OpenFlow router or switch. • User Client. Content Server Anycast Manager Autonomous System 1 Anycast Manager Autonomous System 2 client client
12- Conclusion: • Our design makes use of OpenFlow to perform the redirection of packets along with using content id in addition to the destination IP to make the redirection decision. • And to enable that we designed a two phase content request, for getting the content id and using it. • The goal is to improve the content server by increasing its serving capacity, with less overhead and more efficient usage of the bandwidth in the whole network..