Network Management

1. Network Management Jacques Labetoulle Professor at Institut Eurécom

2. Overview • 1st part : Introduction • Definition • Architectures and functions • Network Planning • 2nd part : standards • Introduction to Object Oriented Approach • OSI standards • Internet standards • Comparison • The TMN • 3rt part : platforms and products • 4th part : Perspectives • CORBA and network management • Other approaches (Web, agents, ...)

3. Introduction • Definition and motivations • Support architecture • Management domains • Network planning

4. Network Management • Definition It is the set of all techniques to implement in order to master the technical, financial, organizational aspects of a private network as well as the access and information security. • Some key words - technical area : quality of service continuity of service - financial area : truth of the prices - organizational area: control of the structure and evolutions - security area : confidentiality access control

5. The network in the enterprise • Strategically important • finance (air plane reservations ) • security (bank transfers) • service (bank notes distributors ) • competition (stock management) • Service obligations • continuity of service • quality of service • adaptability (on demand evolutions) • cost control

6. Complexity of networks • Network evolutions centralized networks ---> distributed networks homogeneous networks ---> heterogeneous networks separated networks ---> integrated networks • Evolution of network utilization • generalization to all kind of personal • opening to external clients or people • multiplicity of services

7. Networks elements in a corporatenetwork • Multiplicity of kinds of equipment communication controllers end of line equipment multiplexers PABX LAN interconnection equipment interconnection networks packet switches computer manufacturers architectures public networks and services • Multiplicity of providers • Rapid technological evolutions

8. Why to manage a network? • Economical reasons • excessive global costs (> 1% of cash flow) • increase of network budget (20% per year) • tractability of prices (multiplicity of services and evolutions) • Complexity increase • offers from operators • generalization of local area networks • sophistication of equipment • Pressure from the users • Internetworking with other networks

9. Management areas Integrated networks Computer networks Data LAN ATM Voice Functional domain Alcatel Bull Accounting Faults Security IBM Configuration Performance TRT Matra SAT manufacturers

10. Network Management today • 1- It exists • 2- It is not satisfactory • No coherent offer • from network operators • from manufacturers • from service providers • Non-adapted standardization

11. Network Management today • Diversity of solutions : a large variety of proprietary systems characterized by: • limitation of management domains --> partial visions • very different ergonomics --> problems of qualification of people • functional limitations --> partial control of networks (faults, performance) • communication difficulties --> partial and local visions multiplicity of work stations • A few intelligence in systems --> necessity of highly qualified persons

12. Network Management tomorrow • Universal workstations • high ergonomics • remote management • multiples visions • adaptation of functions to needs • help systems • automation • possibilities for evolution and adaptations • An adapted standardization • Integration of new techniques

13. Users’ point of view • Coverage of the solution and integration • the whole enterprise (and not only the headquarters) • integration : network, systems, applications, services • integration : all kinds of elements (voice, data, ...) • To day advance • very variable • Partners • manufacturers, software editors • Difficulties (by order of importance) • training, • performance of the offer, • interoperability • ... cost

14. Introduction • Definition and motivations • Support architecture • Management domains • Network planning

15. Principles for an architecture • A logical architecture • definition of elements • A physical architecture • how to connect elements • A set of functions • definition of usage • A methodology • conception, evolution of the management system

16. Integrator machine Integrator machine Integrator machine Agent Agent Agent Agent Agent Agent Agent Agent Architecture Other management systems (PNO) EMS EMS EMS

17. Architecture : the EMS's • Close vision of a sub-area • Proprietary interfaces with equipment (now) • Normalized interfaces with the integrator • Independence from manufacturers and equipment • Possibility of "migration" of functions between Integrator and EMS's

18. Architecture : the work stations • High quality ergonomic • Specialization of operators - access security - control of different visions • Direct access to information

19. Architecture : The integrator system • A set of functions - for universal needs - easy adaptations • flexibility (centralization/distribution) • Basic components - exchange procedures - man/machine interface management - information system - functions - intelligent systems

20. Architecture : The integrator system • A sufficient vision of problems - notion of "view" of sub-networks • Reasonable performance - installation dimensioning - portability on a set of machines

21. Introduction • Definition and motivations • support Architecture • Management domains • Network planning

22. Classification of functionsreal time / differed time activities • Real time activities - behavior supervision - detection of incidents, fault diagnostic - launching of rerouting procedures , maintenance, etc. - access control to services and resources • Differed time activities - network configuration management - access and security rights management - financial management : cost affectation , bill verification - edition of statistics and dash boards - planning, simulation

23. Classification of functionsareas breakdown • 5 areas defined by OSI - Configuration management - fault management - Performance management - accounting - Security management

24. configuration management • Management of the Information base (MIB) - Inventory of network elements - Management of names of managed elements - add, delete, change of network components - Initialization and modification of parameters, states, ... - Modification, creation, suppression of relations between managed elements • Network visualization - Global visualization - Geographical Zooms - Sub-networks visualization - On demand display of managed elements characteristics

25. Configuration management(continued) • Reconfiguration - Activation of stand by configurations - resources re-affectations - Remote software loading - Edition of operational state modifications - History of reconfigurations • Creation of directories - Directory of offered services - Directory of users - Directory of furnishers

26. Fault management • Fault detection - Creation of misbehavior reports - Management of counters and alarm thresholds - Event filtering (elimination of redundant information) - disfonctionnement display • Fault localization - Analysis of alarm reports - Launching of measurements and tests ==> Computer assisted diagnosis • Initialization of corrective actions - Resource re-affectations - Re-routings - Traffic limitations ==> Decision support system - calling to maintenance

27. Fault management (continued) • Equipment recovering - Launching of behavior tests - Backup systems management • Recording of fault histories ("trouble tickets") • Establishment of statistics - breakdown probabilities - duration of incidents - Duration of repairing • Interface with users - signaling of incidents by users - information to users

28. Accounting • Resource usage measurement - Recording - Creation and management of record files • Control of quotas by user - establishment of current consumption - Verification of consumption authorizations • Follow up and control of expenses - recording of up to date tariffs (from operators) - management of taxation tickets - real time evaluation of current consumption - bill control - follow up of equipment costs (investments, deadening, maintenance) - follow up of exploitation costs

29. Accounting (continued) • Financial management - cost splitting (by service, by user, by application) - Analysis and prevision of expenses - Study of scenarios for cost minimization • Internal billing - Management of users - Management of tariffs - Creation of taxation tickets and bills - Bill control - Recording of historic

30. Security management • Security of Network Management - Management of access rights to working stations - Management of operator "views" - Access control to management information • Access control to the managed network - Functions dedicated to the mechanisms : definition of usage conditions activation/deactivation of mechanisms modification of parameters management of authorization lists (to machines, services, network elements)

31. Security management (continued) - Tracking of access (identity, time, destination) - Detection of fraudulent access attempts recording statistics setting of alarms • Information Security - Management of protection mechanisms - Management of encryption and decryption keys - fault detection - Detection of fraudulent attempts

32. Performance management (Real time) • Recording of performance measurements - Definition of measurement conditions criteria - Management of information collecting and filtering - Establishment of statistics - Launching of on demand measurements - Management of information files • Monitoring of network behavior - Visualization resource utilization - Signaling of threshold overpass

33. Performance management Real time (continued) • Performance measurement analysis - Network behavior load repartition throughputs response times availability - Analysis of probable reasons of threshold overpass correlation with equipment faults indicators comparison and correlation ==> computer aided system

34. Performance managementReal time (continued) • Corrective and preventive actions - Resource re-affectation modification of configuration parameters traffic routing optimization - Traffic Limitations filtering, priorities - Choice of action mode ==> computer aided system • Follow up of actions results - Recording of historic - Analysis of action efficiency, definition of rules

35. Performance managementDiffered time • Information analysis - Establishment of statistics and historic - Establishment of quality of service indicators - Edition of reports (periodically or on demand) - Edition of dash boards • Provisional analysis - Elaboration of traffic matrices - Evaluation of performance detection of saturation risks simulation of scenarios ==> improvement of the QoS balancing of resource utilization - Network planning et dimensioning - Follow up of corrective management

36. Other management areas • Planning (see later) • Park management (inventories, catalogue, installations, ...) • Cabling management • License management • Host management (users, disks, versions, ...)

37. Introduction • Definition and motivations • support Architecture • Management domains • Network planning

38. Time scales Scale operations actions minutes supervision observation of network real time management problem detection corrective actions hours day to day maintenance days management statistics (performance, traffic) configuration programmed operations security installations

39. Time scales weeks operation management purchases months financial management billing corrective management re-dimension modifications (routings, ...) year short term topological evolutions planning dimensioning, routings, ... choice of support services annual budgets > 1 year Strategic or strategic decisions long term planning choice of target structures evolution towards these structures evolution plans

40. Important steps • Evaluation of traffic needs • Choice of a target structure • Choice of support services • Dimensioning and optimization • Verification

41. Traffic needs Problem : find an adequate traffic representation • telephony : volumes easy to measure notion of heavy load hour (per site, per link, ...) traffic measure : the Erlang • data : measure unit : packets, transferred octets, bandwidth needs Often : global measures (heavy load hour, possibility of differed transfers, ...) Do not forget protocol’s overheads!

42. Traffic needs • Empirical rules : heavy load hours : 20% of the daily traffic on 8 hours or 16% for 12 hours ; or 14% for 24 hours heavy load hour traffic = 2,5 times the mean hourly traffic mean traffic at heavy hours : V/3600 (in bit/s or messages/s) • Other method : calculate the traffics per hour (no heavy hour traffic problem)

43. Evaluation of traffic needs • 1- Extrapolation of traffic matrices • organize measurement campaigns (per week, month, year, ...) • calculate representatives values, per period • global volumes • heavy hour volumes • utilize mathematical techniques for chronological series extrapolation (linear regressions, Kalman filtering, ...) • correct, taking into consideration the impact of new services • Can use directly network management measures and techniques.

44. Evaluation of traffic needs • 2- Direct analysis of flows • analysis of the structure of the enterprise (types of entities, organization levels, ...) • analysis of the relations and applications used • evaluate elementary flows and integrate them • how to proceed : inquiries • necessity of a validation (by direct measurement of existing flows)

45. Choice of a target structure • Problem • Determine main orientations (strategic choices) : • meshed or star network • where to implement transit centers • choice of structures from the market (manufacturer networks, private network, based on PNO’s networks and services , security aspects , redundancy, ...) • fundamental technological choices : kind of LAN, migration towards ATM • Remark : mixing of technical and political problems

46. Choice of a target structure • Problem : determination of the basis of the solution • Start from the needs, characterized by • traffic volumes and characterization (sporadic, interactive, big transfers, ...) • constraints : costs, performance, security • offers : technical constraints , tariffs, performance, easy of use, ... • Method : a lot of logic and common sense • take into account scales economy • integrate traffics leads to economies • use of elementary rules • regular traffics ===> dedicated networks • sporadic traffics ===> switched networks • variable traffics ===> virtual private networks • look carefully at pricing principles

47. Dimensioning and optimization Basic techniques 1- Inversion of performance evaluation formulas telephone networks : B(A,N) = Erl (A,N) = AN/N! / (1+A+A2/2+ ....+ AN/N!) data links (Kleinrock’s independence assumption) : W = 1/(Ci - Di) • In fact, dimensioning is often made by using a maximum utilization factor (60 or 70% of capacity).

48. Dimensioning and optimization (follow up) 2- Economical optimization formalize the problem as an objective function minimization problem (the cost), subject to constraints (arcs and nodes capacity, performance, ...) elementary costs may depend on non trivial functions (step functions) To solve the problem : OR techniques (linear or integer numbers programming, ...., simulated annealing). in general, problems are NP-complete and can be solved only by heuristics • Results of this step : a dimensioned network, the routings, installation and exploitation costs (monthly costs, maintenance costs, ...)

49. Dimensioning and optimization Example of a formalization problem • Min C =  Cj ej +  Ci,j ei,j +  CRj ej installation of a concentrator in j ; cost of the link between i and j ; cost of the link from the concentrator j to the central node. ei : 1 if a concentrator in j, 0 if not ei,j : 1 if site i is linked to site j (concentrator’s location) , 0 if not With the constraints : i ei,j = capa capacity of the concentrator j ei,j = 1 only 1 link between two sites j ei,j ej= 1 each link towards a site with a concentrator

50. Verification of the solution • The solution needs to be validated : • simplifies assumptions (performance) • necessity to validate for each time slot • How to proceed : • analytical methods (queuing theory) • event driven simulation (also useful to analyze evolutions of the networks)