The Network Performance Advisor

J. W. Ferguson

NLANR/DAST & NCSA

Acknowledgements

• NLANR/DAST does its work on ‘The Advisor’ under a cooperative agreement with the National Science Foundation

• The Internet2 E2E Initiative and the piPEs project have provided support and encouragement throughout

• The Network Measurement Working Group of the Global Grid Forum, for the schema work being done to allow data sharing between measurement projects

Advisor OverviewTargeted for end users & network engineers, the Advisor

measures, displays, and analyzes network metrics

• Uses existing diagnostic tools by integrating them into a common framework

• For network engineers & administrators, provides an easy to use interface to view network metrics, and customize which metrics you like to monitor

• For end users, Advisor attempts to emulate a junior-level network engineer with its Analysis Engine

• Uses the schema in development by the GGF’s Network Measurement Working Group.

• Additional tools and analyses can be added easily

http://dast.nlanr.net/projects/advisor

Current Status

• Version 1.2 released November 2004.• Code freeze for Version 2.0 on 28 February.

Release will follow within a week.• ‘Bundles’ included in release will include Iperf,

OWAMP, ping, top, pathchar, ifconfig, traceroute, netstat, and pathload

• All code is accessable via anonymous CVS.

ArchitecturePerformance Data Collector (PDC)

• Gathers network performance data

Performance Data Historical Archiver (PDHA)

• Archives network performance data

Analysis Engine• Analyzes network data• Provide plain text advice to solve

problems or increase performance

User Interface• Expert Interface: table & tree of metrics• Map Interface: graphical display of network• Analysis Interface: interact with Analysis Engine

All components written in Java and use XML-RPC

Performance Data Collector (PDC)• Designed to be stand-alone, extensible, and portable

• Elegantly handles platform differences and unavailability of any given measurement

• Overview of Features– Uses bundles to facilitate integration of performance data measurement

tools

• A collection of scripts or Java classes that describe:– How to invoke a measurement tool

– What metrics the measurement tool measures

– How to parse the measurement tool's output

– Implements an XML-RPC interface• getAllMetrics: returns the list of metrics that may be measured

• getMeasurement, getMeasurements, getAllMeasurements: returns an individual, a list, or all measurements given a remote host

PDC Features– All requests are fulfilled immediately without any caching – Activation

• Allows cooperation of both ends through a mechanism called activation (i.e. for tools such as Iperf)

– Security

• Using SSL and username/password (more to come)

– Autoupdating

• Periodically updates the bundles (automatically)

• User can set how often to check for updates

• All system bundles updated

• Tool to update bundles on demand

– Global Grid Forum NM-WG Response Schema• Full Java class support for reading and writing in the schema

– Bundle support for NM-WG Response Schema

– Version 2.0 will use the NM-WG Request Schema

Performance Data Historical ArchiverShort to medium-term storage of PDC measurements

• Overview of Features:– Act as a caching proxy for the PDC

• Specify how much data to store, and for how long.

– Utilizes an XML-RPC interface to retrieve data• Clients can retrieve old measurement results and the latest measurement

results• Clients can force PDHA to request new measurements from PDC

– To retrieve archived measurements specify an • interval: returns all measurements taken during the specified interval • list of timestamps: returns all measurements that match a timestamp in the

list, with some amount of error allowed.

– Allow different measurements to have different “lifetimes”– Stores data on disk in XML file– Ability to query third party databases with the NM-WG Request

schema (v. 2.0)

Analysis EngineAnalyze metrics for a specific end-to-end path and give advice to solve performance or connectivity problems

• Features:

– “Test Definition Files” (TDFs) similar to PDC’s ADFs• TDFs consist of

– detection rules: simple binary operations (AND, OR, NOT, etc)

– synthetic metrics file name

– problem descriptions, and solutions

• Synthetic Metrics– operations on base metrics

– may be written in any scripting language (and eventually Java)

– Constructs a decision tree for each problem

Analysis Engine

• Example TDFS include: – Duplex mismatch, incorrect buffer sizes, incorrect settings, congestion,

general connectivity issues.

• Future Development:– Relate TDFs to each other (in v. 2.0)

– Group TDFs into families

– Modify Analysis Engine to use historical data

– Engage the network engineering community to obtain more analysis test cases

– Bi-directional testing (in v. 2.0)

Displays Advisor’s collected network metrics and is capable of displaying outside metrics acquired in the GGF’s NM-WG schema.

• Three main graphical displays

– Metric Display GUI: Displays all metrics• uses a tree to organize metrics• uses a table to display metrics and corresponding information

– Analysis GUI: Displays advice reported from the analysis engine• text display of analysis and advice

– Map GUI: Visual display of the network and trouble spots• users will be able to click on a map to view measurements for specific

areas along the path

Advisor GUI

Thank You !

dast.nlanr.net/projects/advisor