1. GEMINI: Active Network Measurements Martin Swany, Indiana University

2. Overview GEMINI is an I&M system based on perfSONAR/LAMP, INSTOOLS and Periscope (updated perfSONAR protocols) o Measurement infrastructure, support services, schemas/metadata Active measurements aren't that special o all measurements should have accurate timestamps o all measurements may perturb a user's experiment o all measurements may perturb other measurements o Active measurements do affect multiple hops

3. Active Measurement Tools OWAMP – One Way Active Measurement Protocol o Can separate forward and reverse path characteristics o Delay measurements – depends on clock synchronization BWCTL – “Bandwidth controller” o Wraps bulk transfer test tools like Iperf o Can provide mutual exclusion for ongoing tests Ping – simple but ubiquitous o 802.1ag defines L2 ping (to be included soon)

4. GEMINI at GEC 14 User marks which nodes are 'active MPs’ in request RSpec Active measurement software infrastructure currently runs on user nodes Instrumentize process installs all the software: o iperf, bwctl, owamp tools o perfSONAR services (pSBUOY, PingER) Web UI provides centralized configuration administration for active measurements o Enable services and tools (bwctl, owamp daemons) o Configure regular testing Nodes run a local service that updates configuration, starts/stops daemons and performs maintenance

5. Performing Active Measurements On-Demand OWAMP and BWCTL permit third-party on-demand measurements o one-way latency, jitter, loss and throughput metrics o must have daemons enabled and running on endpoints and OWAMP requires coordinated clocks These tools also provide rudimentary coordination o e.g. BWCTL will serialize throughput measurements on same node Regular Testing Users can configure regular OWAMP, BWCTL and Ping testing Data is stored on nodes that perform the measurements (MySQL) perfSONAR services store metadata about measurements and make the data available for querying o metadata includes: endpoints, tool and parameters used o data always includes a timestamp Data from regular testing can be visualized in browser or queried (for raw data)

6. Future Issues Single framework for measurements o make it easy to extend, add new tools and metrics o reuse scheduling, authentication, coordination, naming, metadata o provide APIs and schemas for the data/metadata o on-demand testing still depends on tools Infrastructure Potentially dedicated measurement nodes with user- accessible data – depends on AA Coordination, sharing of active measurements Selective/on-demand installation of software Proper quantification of measurement errors and experiment perturbation o Instrumentation of the measurement software.