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Route Optimization Abilene Route Quality Control Initiative Aaron D. Britt [email protected] Guy Almes [email protected] June 11, 2002 Problem Statement(s) •How does Internet2 continue to add to its initiative of “Superlative Networking” ? •Does the Abilene backbone outperform the Commodity Internet? •What problems are there, if any, regarding the routing over the Abilene Backbone? Series B -2- Internet2 Route Optimization Objective •Increase the Performance of the Internet2 Infrastructure •Use Route Optimization Technology to gather Performance Metrics for the Internet2 Network •Use the captured data to Identify Problem Areas and report overall how the Abilene Network is Performing •Identify Solutions for any problems discovered •Implement a given subset of these solutions, if they make sense. Series B -3- What is BGP Route Optimization? •Definition: Continually (or periodically) determining the performance of various links (routes), measured through the use of active probes, and weighting those measurements based on tunable metrics and weights. •Simply put, using additional intelligence to measure and define the performance of a route, above and beyond that of the standard BGP metrics. Series B -4- Capture Performance Metrics •What Metrics are Important? •Latency - The time it takes to get information through a network. Measured for the round trip. •Packet Loss - Packet loss reflects the amount of packets sent through a given network that when sent from a host never reach the intended destination. •Unreliability – How reliable the route is or is not based on a sub-set of metrics. •Route Asymmetry Series B -5- Metrics Gathered and Calculated • OpScore • Algorithm based on the probe data weighted, normalized and calculated based on customer defined settings (Min/Max/Weight). – – – – – Latency Unreliability Congestion Points Layer 3 Hops Carrier Preference (Least Cost Routing) • The route with the lowest score wins! Series B -6- How to gather these Metrics •High Level Architecture •Orbit1000-CPE •Orbit1000-Stats •Private AS Space eBGP Multihop Commodity Internet AS 64701 AS 64701 PROBES Abilene Router Orbit1000 CPE Internet2 Series B -7- Type of Probe •UDP Based •ICMP - Routers drop ICMP •TCP – Sets off IDS systems •UDP probe, though proprietary in nature, very similar to that of a typical traceroute. •UDP Probe data is within 2% of the accuracy of TCP probe data, but it doesn’t set off IDS systems. Series B -8- Probing Mechanism •Where should we send the probes? • Prefix list we receive from the Internet2 edge router • ’Prefix + 1’ methodology, unless a more specific IP address is specified in the discovery-include list • Using a bisecting search algorithm that finds the endpoint while minimizing traffic. – Based on ICMP response (did we get there or not) – When the probe reaches an endpoint, or it runs out of TTL’s, we blast out any missing/remaining TTL’s •Using the Source Port and Destination Port we can track the probes, where they went and why. Series B -9- Where does all the Data Go? •Probe Data is stored and collected in a central CORE – SQL dB. •All Probing Devices store their data in the same CORE PROBE DATA PROBE DATA orb01.i2.annarbor orb01.i2.armonk CORE Series B -10- The CORE •Responsible for: • Data Collection & Storage • OpScore Calculation CORE View Optimizer Balancer SQL dB Reporting Engine Series B -11- Reporting Engine •Web Interface •Graphical and Analytical •Summary Statistics •Can drill down to the packet of each probe sent Series B -12- Identify Problem Areas •Identify Problem Areas •Throughput and Latency Issues – Jitter – Packet Loss – Congestion Points •Routing Issues (Misconfigured?) – Asymmetry – Routing Loops – Black Holes? •What else will we find? Series B -13- Project Scope • Install probe devices – 1 GigaPOP at a time • Probe Internet2 prefixes over both Internet2 and commodity internet • Collect data • Tweak metrics • Report on published results • Define recommended changes based on analysis of data. Series B -14- Project Timeline •Armonk site installed – 1st week of April •Merit GigaPOP – 1st week of May •Determine on ICB, which POPs to move forward through summer months •Start to review data July through August Series B -15- Internet2 and Opnix Collaboration Abstract: With the advancement of powerful applications on the Internet, the improvement of Internet performance to enable these applications can be a difficult challenge. Opnix, Inc. has developed route control and performance enhancing tools to help address these challenges in ways not done previously. Internet2, the well-known next generation network, will work closely with Opnix to exploit these tools and technology. Internet2 and Opnix will work in the Internet2 environment to monitor and improve the technology’s based on what we learn together. Sharing the results with the Internet2 community to further the advancement of next generation applications will be the goal. Series B -16- Internet2 and Opnix Endgame •Establish baselines of performance for Internet2. •Verify the Internet2 network should be preferred over commodity Internet for Research/Education destinations. •Illuminate performance inhibiting issues from network to continue with leading edge performance. •Develop next generation applications for detection of performance inhibiting issues. •Support Internet2 engineers with the use of next generation Route Control technology. Series B -17-