The Management Infrastructure of a Network Measurement System for QoS Parameters

1. The Management Infrastructure of a Network Measurement System for QoS Parameters Alexandru Bikfalvi, Paul Pătraş, Mihai Cristian Vancea, Virgil Dobrotă Technical University of Cluj-Napoca Communications Department 26-28 Baritiu Street, 400027 Cluj-Napoca, Romania, Tel/Fax: +40-264-597083

2. Agenda • Scenario based on existing tools • Overview of a network management system • Design of the management infrastructure • Experimental results • Conclusions and future work

3. Existing Tools Scenarios • Vendor specific applications for specific platforms • Not all applications are QoS capable • Some require complex commands, scripts, procedural steps • Manual measurement control (especially on different tools) • Additional software and computations to obtain targeted results Measurement Applications Tested Network

4. Our Software Solution Management Console Console • Straightforward user interface • User focuses on scenarios, topology, test objectives • Runtime operations performed by the computer • Measured QoS parameters available automatically Infrastructure • Software module used by both applications • Measurement information communication • Accomplish the task using a management protocol Network Measurement System Measurement Agents Tested Network Management Station

5. A comprehensive management architecture is usually specific to a management technology Network Management Overview Architecture – collection of… • Managing devices – management stations • Managed devices – network elements • Management messages – management protocol Managers Agents

6. Managers and Agents Managers handle management tasks • Network Management Systems (NMS) or Operation Support Systems (OSS) • Communicate with the agents within the managed devices • Provide a console or an interface for user administration • Perform predefined or user-defined automated actions Management Console QoS Measurement Agent Agents run on managed devices • Service managers’ requests • Notify of unexpected events

7. Message Communication It is done using a management protocol such as SNMP, CMIP Polling… Request message sent to the agent Process request and reply back An event occurs Event-driven… ! The event is processed A notification is sent to inform the manager

8. Must provide a base of identifying those objects • Must be build on widely accepted rules • Should contain the managed objects and their relationships Management Information • Meaning of data transported by the management protocol between the managers and the agents There are many What is required • Manufacturers Repository of manageable information • Equipments • Applications • Parameters

9. Infrastructure Design Structural Logic Sessions Organizes measurement operations as a set of abstract items Groups The user interacts with these items to perform a measurement Tasks Management Messages NMS Management Identification messages relay information about agents’ capabilities Task control messages request agents to start a measurement task Data messages are used to collect QoS results from a set of agents

10. Infrastructure Design The fundamental QoS measurement scenario A data structure comprising the agents and parameters used in the QoS test Reusability: can be saved and later loaded Several sessions mapped with one reference Contain unrelated sessions distributed in time Based on a single session with a variable parameter A session or a group to be executed The start time can be user-defined The execution process done entirely by the management software

11. Infrastructure Design Defining Sessions Agent 2 • Agent (s) involved Agent 3 Session 1 • Generation / Analysis Agent 1 Agent 1 ► Agent 3 • Traffic type • Packet distribution Session 2 • Protocol specific • Desired results Agent 2 ► Agent 4 Scheduling and Running Tasks Task 1 (finished) (running) (pending) Session 2 @ 1 o’clock Agent 4 Task 2 (pending) (running) Session 1 @ 3 o’clock Collecting Results QoS Parameter Management Station Time

12. The management infrastructure uses the Simple Network Management Protocol Management Messages Structure of Management Information Access Procedures Management Station Agent iso 1 Set Request Object Classes Request Response org 1 3 connection Get Request 2 dod 6 system Request Response internet 1 traffic 3 Get Request 3 experimental advanced 4 Response

13. Session Manager SNMP Service User Interface Management Service Queuing Service Software Architecture • Enables user control through various windows and dialogs Measurement Services • Allows creation of measurement sessions, groups and tasks • Management console’s QoS measurement intelligence Management Console • Runs the measurement task; collects and stores results • Synchronous service for asynchronous messages Communication Services • Message retransmissions, duplicates deletion, timeout • Encapsulation of messages to SNMP PDUs Management Console • SNMP data verification, buffer overflow checking Measurement Agent • A thread for each assigned local network interface • Socket I/O operations with SNMP data

14. The primary application that enables the users to perform QoS measurements Management Console GUI Configuration Service Service Control Manager Session Manager Task Scheduling Message Wrapper Hardware Manager Queuing Service SNMP Service Management Service

15. Task SNMP Message Message Message ACK Message Message Message Message Message Running Core Services I want to schedule my first measurement task using Agent 1 GUI SessionManager Pending Running Queuing Service Level 4 Level 3 1 2 0 Level 2 Level 1 Outbound Level 4 Level 3 Level 2 Level 1 Inbound SNMP Service Management Service

16. Experimental Scenario Agent Objectives 1Gpbs SysKonnect • SysKonnect system performance Agent • Throughput 1000 Base SX Measurement Endace DAG • Packet delay variation • Packet loss Cisco Catalyst 2950 Parameters • Frame rate: 200 to 100,000 pps • Frame size: 1500 bytes Management Station • Test duration: 100 seconds • Packet distribution: periodic

17. Experimental Results • Series of tests vs. packet rate at 1500 byte frames • Packet count • Throughput • Delay variation • Packet loss ratio • Real-time failure Almost 700 Mbps 6 million packets per 100 seconds test Up to 4 milliseconds Up to 6.5 percent

18. Conclusions and Future Work Advantages • Faster experiment setup and results processing • No human attendance during testing required Future Work • Extra features to make network testing easier to perform • User focuses on experiment target rather on implementation • Extend support for other management protocols • Greater availability of data after a test is completed • Improve communication control procedures between management console and agents • Include support for other networking technologies Drawbacks • Not portable on all existing platforms • Not optimized for local resources usage and all measurement procedures • Does not implement a fine-grained analysis to conserve management bandwidth

19. Thank You