1. POSTECH DP&NM Lab 1 Overview of Network Management J. Won-Ki Hong Dept. of Computer Science and Engineering POSTECH Email: jwkhong@postech.ac.kr

2. POSTECH DP&NM Lab 2 Table of Contents Today’s Networks Network Management Requirements Network Management Systems NMS Software Architecture Distributed Network Management Proxy Agent Standard Management Frameworks

3. POSTECH DP&NM Lab 3 Fast Ethernet B-ISDN ATM SDH PSTN Computer Networks Telecom Networks Today’s Networks & Services ISDN Token Ring Gigabit Ethernet MPLS WANs SS#7 IN/AIN PSDN PCS Access Networks Ethernet World-Wide Web Email, DNS, FTP News, Telnet, IRC RealAudio, RealVideo MBone Video Conferencing Electronic Commerce Internet Phone Banking, Accounting Distance Learning Local, Long-distance, Oversea Phone service 080, 070, collect-call third-party IN service cellular, C2, PCS, TRS Video-on-Demand Tele-conferencing Video-conferencing Internet Telephony

4. POSTECH DP&NM Lab 4 NM Users’ Requirements Controlling corporate strategic assets –effective control of network & computing resources Controlling complexity –continued growth of devices, users, applications & protocols Improving service –users expect better service with increased resources Balancing various needs –must assign and control resources to balance various needs Reducing downtime –more users and applications depend on availability Controlling costs –effective resource utilization in order to control costs

5. POSTECH DP&NM Lab 5 NM Functional Requirements Fault Management –detection, isolation and correction of abnormal operations Configuration Management –identify managed resources and their connectivity, discovery Accounting Management –keep track of usage for charging Performance Management –monitor and evaluate the behavior of managed resources Security Management –allow only authorized access and control FCAPS

6. POSTECH DP&NM Lab 6 Fault Management concerned with: –providing a reliable networking environment –ensuring that the systems as a whole, and each essential component individually, are in proper working order –redundant components and routes can be used to increase fault tolerance when a fault occurs, the manager should be able to: –determine exactly where the fault (i.e., abnormal condition) is –isolate the rest of the network from failure –reconfigure or modify the network for continued operation –repair or replace the failed components to restore the network

7. POSTECH DP&NM Lab 7 Configuration Management concerned with: –initializing a network & shutting down part or all of the network –maintaining, adding and updating the relationships among components –monitoring the status of components during network operation the network manager should be able to: –startup and shutdown operations on a network –identify the components that comprise the network (discovery) –change the connectivity of the components (possibly as a result of network upgrade, fault recovery or security checks) –detect changes in the network configuration

8. POSTECH DP&NM Lab 8 Accounting Management concerned with: –keeping track of the usage of network resources –charging the use of network resources –monitoring the end-user activities for possible abuse, for suggesting better usage to users and for network planning the manager should be able to: –specify the kinds of accounting information to be recorded at various nodes –specify the algorithms to be used in calculating the charging –generate accounting reports

9. POSTECH DP&NM Lab 9 Performance Management concerned with: –providing an efficient communication environment –monitoring and analyzing the performance of the components –making proper adjustments to improve network performance the manager should be able to: –determine the capacity utilization, throughput, the average and worst- case response times –monitor and gather data on the activities of components –analyze the gathered data and assess performance levels –determine the sources of performance problems & fix them –use the performance stats for future network planning

10. POSTECH DP&NM Lab 10 Security Management concerned with: –providing a secure networking environment –preventing hacking, illegal and unauthorized access –managing information protection and access-control facilities the manager should be able to: –generate, distribute and store encryption keys –maintain and distribute passwords and other authorization or access- control information –monitor and control access to networks –collect, store and examine audit records and security logs –enable & disable the logging facilities

11. POSTECH DP&NM Lab 11 Network Management Systems A network management system (NMS) is a collection of tools for network monitoring and control based on the manager-agent paradigm –the manager sends mgmt requests to one or more agents –an agent performs the requested operation and returns results –when agents detect faults and they report to the manager NMS typically provides a GUI through which most or all management tasks can be performed Many commercial and freely available NMSs exist: –HP OpenView, IBM NetView, Sun Net Manager, etc. –research prototypes from CMU, MIT, UC Davis, U. of Twente

12. POSTECH DP&NM Lab 12 Agent Collect, organize & interpret Operational Data Administrator Workstation Management Platform Observation & Control mgmt requests/replies event reports

13. POSTECH DP&NM Lab 13 Elements of an NMS NMA NMEAppl Comm OS NMEAppl Comm OS NMEAppl Comm OS NME Comm OS Network control host (manager) Server (agent) Workstation (agent) Router (agent) NMA = network management application NME = network management entity Appl = application Comm = communications software OS = operating system Networks

14. POSTECH DP&NM Lab 14 Network Management Entity (NME) NME is a collection of software devoted to the network management tasks is typically known as an “management agent” Each NME performs the following tasks –collects statistics on communications and network-related activities –stores statistics locally –responds to commands from the network manager, including commands to: transmit collected stats to network manager change an attribute value provide status information generate artificial traffic to perform a test etc.

15. POSTECH DP&NM Lab 15 Network Mgmt Application (NMA) NMA is a collection of software for performing network monitoring and control is typically known as “network manager” NMA provides an operator interface to allow an authorized user to manage the network NMA responds to user commands by displaying information and/or issuing commands to NMEs Standard protocols (e.g., SNMP, CMIP) are used to manage a multi-vendor network there may be more than one NMA in a large network which can lead to the need of a hierarchy of managers (e.g., top level manager, middle level managers, etc.)

16. POSTECH DP&NM Lab 16 NM Software Architecture User Presentation Software –interfaces between user and NM software –a unified user interface desirable –includes graphical tools to display summarized NM information Network Management Software –a set of NM applications (configuration, performance, etc.) –a set of application elements (alarm handling, logging, etc.) –NM data transport service Communication and Database Support Software –local Management Information Base (MIB) access module –communications protocol stack (e.g., TCP/IP, OSI) to interact with remote agents and managers

17. POSTECH DP&NM Lab 17 Architectural Model of NMS Unified user interface Presentation of network management information to users Network management application Network management application... application element Network management data transport service MIB access module Communication protocol stack Managed networks... Management Information Base

18. POSTECH DP&NM Lab 18 Distributed Network Management Resources to be managed are widely distributed –widespread use of departmental LANs –need for local control & optimization of distributed applications Hierarchical NM architecture desirable –distributed NMSs are given limited access for network monitoring and control of departmental resources –top-level NMS has a global access rights and the ability to manage all network resources Benefits of Distributed NM –NM traffic overhead is minimized - traffic is localized –Dist. mgmt offers greater scalability –use of multiple NMSs eliminates the single point of failure

19. POSTECH DP&NM Lab 19 Typical Dist. Mgmt System Architecture Management clients (PCs, workstations) Network Management server Management application MIB Element manager Element manager Network resources (servers, routers, hosts) with management agents Management server Management application MIB

20. POSTECH DP&NM Lab 20 Proxy Agents Managed resources may have various mgmt interfaces –some with different mgmt protocols (e.g., OSI vs. SNMP, XML vs. SNMP) –some with proprietary mgmt interfaces (e.g., older systems) –small systems not capable of possessing NME (e.g., modems) Proxy agents are used to manage these devices –managers use standard protocols to communicate with proxies –proxy agents use proprietary protocols to communicate with proprietary devices –proxy agents perform translations between managers and proprietary devices –an agent to the manager and a manager to proprietary devices

21. POSTECH DP&NM Lab 21 Proxy Agent Architecture Proxy Agent Protocol stack Client proxy stub Protocol stack Proprietary management interface Server proxy stub Management application Client stub Protocol stack Server stub Protocol stack Standard operations and event reports Proprietary operations and event reports

22. POSTECH DP&NM Lab 22 Standard Management Frameworks Internet Network Management Framework (IETF) –SNMPv1 (Internet Full Standard) –SNMPv2 (Internet Full Standard) –SNMPv3 (Internet Proposed Standard) OSI Network Management Framework (ISO/ITU-T) –CMIP (X.700 Series) Telecommunication Management Network (ITU-T) –TMN (M.3000 Series) Web-based Enterprise Management (DMTF) –CIM, XML, Web Services

23. POSTECH DP&NM Lab 23 Summary Network Management Requirements –Users’ Requirements –Functional Requirements (FCAPS) Network Management Systems –Network Management Entity (NME) –Network Management Application (NMA) NMS Software Architecture Distributed Network Management Proxy Agent Standard Management Frameworks

24. POSTECH DP&NM Lab 24 Useful Internet Resources Web Sites –http://snmp.cs.utwente.nl/ (SNMP, NM RFCs) –http://www.itu.int/ITU-T/studygroups/com04/ngn-mfg/index.html (NGN Management Focus Group) –http://www.tmforum.org/ (TM Forum) –http://www.ietf.org/html.charters/wg-dir.html (IETF) –http://www.dmtf.org (DMTF)

25. POSTECH DP&NM Lab 25 Questions?