An Approach for Efficient Accurate and Timely Estimation

An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Hongbin Luo, Zhe Chen, Jianbo Cui, Hongke Zhang Beijing Jiaotong University The 17 th IEEE Global Internet Symposium April 28, 2014, Toronto

Roadmap 1 2 Motivation 2 Requirements and Implications 3 A Possible Internet Architecture 4 Performance Evaluation 5 Conclusion and Future Work An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

1. Motivation What is a traffic matrix (TM)? A TM describes the traffic volume (packets/ bytes) between an ingress and egress (IE) node pair in a network. The traffic matrices are critical inputs to many aspects of network functions such as traffic engineering, capacity provisioning, and anomaly detection. Therefore, network operators desire to obtain accurate evaluations of the traffic matrices of their networks. Under the current Internet architecture, however, it is extremely challenging to accurately, efficiently, and timely measure the TM between IE node pairs. 3 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

1. Motivation Why is it extremely challenging? ü First, the TM in many networks is not directly observable. Instead, it can only be estimated through link load measurements. ü Second, the collected large amount of per flow/packet information has to be transported to a centralized location for correlation. But Correlation: p is time-consuming: so, TM estimation cannot be timely; p relies on high-performance servers: TM is not efficient; p relies on inputs from different nodes that have different observations: TM is not accurate. ü Third, the TM estimation has to be done at very high speed since an Internet service provider (ISP) may forward data packets at a speed of over one Terabits per second (Tbps). 4 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

1. Motivation In addition, the current Internet faces other serious issues (such as poor security and scalability) that cannot be remedied by incremental changes. Therefore, in recent years there are increasing efforts in developing “clean-slate” redesigns of the Internet architecture, aiming at rectifying one or more of these problems through non-incremental changes. 5 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

1. Motivation So, the problem is: ü Could we design a future Internet architecture that makes it easy for network operators to accurately estimate the traffic matrices of their networks in an efficient and timely manner? 6 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

Roadmap 1 7 Motivation 2 Requirements and Implications 3 A Possible Internet Architecture 4 Performance Evaluation 5 Conclusion and Future Work An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

2. Requirements and Implications Requirements for TM estimation ① Accurate estimation: Novel technologies such as Open. Flow requires that the estimated traffic matrices are accurate since if otherwise, the controller may make wrong decisions when computing paths for flows. ② Timely estimation: Network managers can make the best use of network resources based on its state-of-the -art network status only when the traffic matrices are estimated in real time. ③ efficient estimation: We desire that the traffic estimation is not dependent on computers with strong computation capability. 8 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

2. Requirements and Implications of requirements ① Accurate estimation: Every byte/packet should be accounted. It is better to use the flow information observed at the ingress node to estimate the TM. ② Timely estimation: TM estimation should be performed during the packet forwarding process. ③ efficient estimation: TM estimation should be performed in a distributed manner, without requiring a centralized node for correlation. 9 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices The future Internet should make it possible for an ingress node to estimate the traffic matrices from it to the rest nodes during its packet forwarding process. Beijing Jiaotong University

Roadmap 1 10 Motivation 2 Requirements and Implications 3 A Possible Internet Architecture 4 Performance Evaluation 5 Conclusion and Future Work An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

3. A Possible Internet Architecture We have proposed a future Internet architecture called Co. Lo. R, whose basic idea is to couple service location with inter-domain routing, but to decouple them from forwarding. We have also built a prototype and demonstrate that Co. Lo. R satisfies many requirements of the future Internet including being information-centric, encouraging innovation, and providing efficient support for mobility, multicast, multi-homing, and middle-boxes. Below we briefly introduce the basic ideas of Co. Lo. R. 11 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

3. A Possible Internet Architecture Basic ideas: I. Using four namespaces: Service identifiers (SIDs): used to name contents. They are flat, self-certifying. Node identifiers (NIDs): used to identify the identity of network nodes. They are flat, self-certifying and 128 bits long. Intra-domain routing locators: used for intradomain routing. Every domain can choose its preferred intra-domain routing architecture and routing locators. Path identifiers (PIDs): used for inter-domain routing. Two domains can negotiate a set of PIDs, as long as the PIDs are unique in each domain. PIDs are not advertised throughout the Internet, but are local to the two domains. 12 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

3. A Possible Internet Architecture Basic ideas: II. Using name-based routing for service location. III. Inter-domain routing for data packet forwarding is determined during the service location process. IV. Intra-domain routing may or may not be determined during the service location process. We leave this for domains’ local policy. V. End-to-end data packet forwarding is based on loose source routing. While some of the ideas are borrowed from existing literature, we believe that: one can see further by standing on the shoulders of giants. 13 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

3. A Possible Internet Architecture Network topology As the current Internet, Co. Lo. R assumes that the future Internet will still centered around domains. Domains have the AS-level provider/ customer/peer relationship. 14 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

3. A Possible Internet Architecture Intra-domain routing Domain 3 uses MPLS for intra-domain routing. Domain 1 uses IPv 6 for intradomain routing. Domain 4 uses Open. Flow for intra-domain routing. A domain can freely choose its preferred intra-domain routing architecture, without considering other domains. 15 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

3. A Possible Internet Architecture Inter-domain routing P 7 R 4 D 2 P 6 R 2 D 1 P 5 R 5 D 6 P 5 P 1 P 6 P 7 P 4 Interdomain routing relies on paths negotiated by two neighbor domains. Nodes in a domaintains the end point of every path that connects the domain to a neighboring domain. 16 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

3. A Possible Internet Architecture Service registration RM 6 Every domain has a logical resource manager. P 5 P 1 The service registration process is similar to that in DONA. Content sources register SIDs to their local RMs, which registers the SID to their peers or provider RMs. 17 RM 5 RM 3 P 6 RM 1 P 7 RM 2 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices P 4 RM 4 Beijing Jiaotong University

3. A Possible Internet Architecture Service location and inter-domain routing RM 6 Users send requests to their local RMs when they want a content represented by an SID. (iii) P 5 (iv) P 1 RM 5 RM 3 RMs forward requests to either the closest copy of the content, or their provider RMs. 18 P 6 (v) RM 1 P 7 RM 2 P 4 (ii) (vi) An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices RM 4 Beijing Jiaotong University

3. A Possible Internet Architecture Service location and routing RM 6 (iii) P 5 (iv) P 1 RM 5 RM 3 Every time a RM forwards a request to a neighboring RM, it appends the path between the two domains onto the request. 19 P 6 (v) RM 1 P 7 RM 2 P 4 (ii) (vi) An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices RM 4 Beijing Jiaotong University

3. A Possible Internet Architecture Packet forwarding Intra-domain packet forwarding is based on the routing mechanism of each domain. (d) (a) (b) (c) Inter-domain packet forwarding is based on PIDs that are determined during the service location process. Every time a border router receives an incoming packet, it strips out the outer most PID in the packet header. 20 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

3. A Possible Internet Architecture TM estimation in Co. Lo. R P 7 R 4 D 2 P 6 R 2 D 1 P 5 R 5 D 6 Every time an ingress border router receives a packet, it reads the outermost PID, and looks up its inter-domain routing table. This way, it knows the egress node of the packet. Accordingly, it simply adds the bytes of the packet onto the TM from the IR to the ER. 21 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

Roadmap 1 22 Motivation 2 Requirements and Implications 3 A Possible Internet Architecture 4 Performance Evaluation 5 Conclusion and Future Work An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

4. Performance evaluation We have built a prototype to show the accuracy of TM estimation in Co. Lo. R and that in Open. Flow. We estimate the traffic matrices from node A to the other nodes B, C, and D, assuming that node D 1 is the source and nodes D 2, D 3, and D 4 are the destinations of packets. While the results are similar, we only report the estimated TM from node A to node C. 23 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

4. Performance evaluation The estimated TM from node A to node C Both Co. Lo. R and Open. TM can accurately estimate the traffic matrices. the duration between two consecutive polls in Open. Flow is shorter than the default value for a switch to remove a flow entry from its flow table. 24 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

4. Performance evaluation The estimated TM from node A to node C Open. TM cannot accurately estimate the traffic matrices. But Co. Lo. R can. the duration between two consecutive polls in Open. Flow is larger than the default value for a switch to remove a flow entry from its flow table. 25 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

6. Conclusions and Future Work Conclusions ü we present the requirements for TM estimation and the corresponding implications on the future Internet architecture. ü we present a future Internet architecture that makes it easy to accurately, efficiently, and timely estimate traffic matrices. ü we describe how to estimate traffic matrices of a network under the proposed Internet architecture. ü we present numerical results to demonstrate the performance of the proposed Internet architecture in estimating traffic matrix. 26 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

6. Conclusions and Future Work ü While we have shown that Co. Lo. R makes it possible to accurately, timely and efficiently estimate traffic matrices, an important question needs to be answered. ü How an ISP could benefit from accurate, timely and efficient estimation of traffic matrices? We will investigate this question in the future. 27 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University

Thanks! 28 An Approach for Efficient, Accurate, and Timely Estimation of Traffic Matrices Beijing Jiaotong University