11-1 Business Data Communications and Networking, 6 th ed. FitzGerald and Dennis

11-2 Copyright © 1999 John Wiley & Sons, Inc. All rights reserved. Reproduction or translation of this work beyond that permitted in Section 117 of the 1976 United States Copyright Act without the express written permission of the copyright owner is unlawful. Request for further information should be addressed to the Permissions Department, John Wiley & Sons, Inc. The purchaser may make back-up copies for his/her own use only and not for redistribution or resale. The Publisher assumes no responsibility for errors, omissions, or damages, caused by the use of these programs or from the use of the information contained herein.

11-3 Network Management Chapter 11

11-4 Objectives of Chapter 11 Become familiar with… u the network management organization u end user support u cost management u several types of network management hardware tools

11-5 Objectives of Chapter 11 Understand u what is required to manage the day-to-day operation of networks u configuration management u performance and fault management u the role and functions of network management software

11-6 INTRODUCTION

11-7 Introduction Network Management: the process of operating, monitoring, and controlling the network to ensure that it works as intended and provides value to its users. Without a well-planned and designed network, and a well-organized network management staff, operating the network becomes extremely difficult. Unfortunately, many network managers spend most of their time firefighting - dealing with breakdowns and immediate problems.

11-8 ORGANIZING THE NETWORK MANAGEMENT FUNCTION

11-9 The Shift to LANs and the Web Since the late 1980’s, there has been an explosion of microcomputer-based networks. Although the management of host-based mainframe networks will always be important, the future of network management lies in the successful management of the LAN, backbone network, and Internet resources.

11-10 The Shift to LANs and the Web Today, the critical issue is the integration of all organizational networks and applications. This presents two problems: First, technical compatibility of technologies and protocols Second, the cultural differences in personalities and management styles of network managers. WAN and mainframe managers prefer more highly structured and controlled environments than do LAN and Web managers.

11-11 Integrating LANs, WANs, and the Web The key to integrating LANs, WANs, and the Web into one overall organization network is for both LAN/Web and WAN managers to recognize that they no longer have the power they once had. The central data communication network organization should have a written charter that defines its purpose, operational philosophy, and long-range goals.

11-12 Integrating Voice and Data Communications Another major challenge, the separation of voice and data worked well over the years, but now changing communication technologies are causing enormous pressures to combine these functions. There is no perfect solution to the problem of integration, because it must be handled in a way unique to each organization. In communications we are moving from an era where the computer system is the dominant IT function to one in which communications networks are the dominant IT function.

11-13 CONFIGURATION MANAGEMENT Managing the network’s hardware and software configuration and documenting it.

11-14 Configuring the Network and Client Computers One of the most common configuration activities is adding and deleting user accounts. Another common activity is updating the software on the client computers attached to the network.

11-15 Configuring the Network and Client Computers Electronic software delivery is one solution to the configuration problems associated with software updates. ESD greatly reduces the cost of configuration management because it eliminates the need to manually update each and every client computer.

11-16 Documenting the Configuration Configuration documentation includes information about network hardware, network software, user and application profiles, and network documentation. Network maps must be supplemented by documentation on each individual network component. A similar approach can be used for network software.

11-17 Documenting the Configuration Software documentation can also help in negotiating site licenses for software. The third type of documentation is the user and application profiles, which should be automatically provided by the network operating system or outside software agreements. In addition, other documentation must be routinely developed and updated pertaining to the network (incl. manuals).

11-18 PERFORMANCE and FAULT MANAGEMENT

11-19 Performance and Fault Management Performance management: ensuring the network is operating as efficiently as possible. Fault management: preventing, detecting, and correcting faults in the network circuits, hardware, and software.

11-20 Network Monitoring Most large organizations and many small ones use network management software to monitor and control their networks. In large networks, network monitoring becomes more important. The parameters monitored by a network management system fall into two distinct categories: physical network statistics and logical network information.

11-21 Network Monitoring Physical network parameters include monitoring the operation of the network;s modems, multiplexers, circuits linking the various hardware devices, and any other network device. Logical network parameters include performance measurement systems that keep track of user response times, the volume of traffic on a specific circuit, the destination of data routed around various network, and any other indices showing the level of service provided by the network.

11-22 Failure Control Function Failure control is handled by the network support group that is called when anything goes wrong with the network (help desk). Failure control requires developing a central control philosophy for problem reporting and other user interfaces. Newer “smart” network devices perform their functions and record data on the messages on the messages they process.

11-23 Failure Control Function Numerous software packages are available for recording fault information. Trouble tickets must be kept if a manager wants do do any type of problem tracking. Problem tracking allows the network manager to determine who is responsible for correcting any outstanding problems. Problem statistics are an important control device for the network operators as well as for vendors.

11-24 Failure Control Function Problem prioritization helps ensure that critical problems get priority over less important ones. Management reports are required to determine network availability, product and vendor reliability and vendor responsiveness. The purpose of the trouble log is to record problems that must be corrected and to keep track of statistics associated with these problems.

11-25 Problem Resolution The purpose of testing and problem management is to establish test and validity criteria and coordinate the various tests. Mean time to repair (MTTR) is equal to the mean time to diagnose plus the mean time to respond plus the mean time to fix a problem. MTTRepair = MTTDiagnose + MTTRespond + MTTFix The mean time between failures (MTBF) indicates the reliability of a network component. One important time factor is availability, the percentage of time the network is available to users. (# of hours available/# hours per period).

11-26 Problem Resolution The network network operations group use automated network management software to gather a daily record of the normal operations of the network. These data can be used for predicting future growth patterns and failures. Such predictions can be accompanied by establishing simple quality control charts.

11-27 Problem Resolution

11-28 Problem Resolution More organizations are beginning to establish service load agreements with their common carriers and service providers, which specifies the type of performance and fault conditions that the organization will accept.

11-29 END-USER SUPPORT

11-30 End-User Support Solving whatever problems users encounter while using the network. Three types: Resolving network problems Resolving software problems Training

11-31 Resolving problems Problems stem from three major sources: Hardware devices A lack of user knowledge Software or software compatibility. There are often several levels to the problem resolution process. Basic help desk Specialized skills personnel with experience in problem areas Technical specialists.

11-32 Providing End-User Training End-user training is an ongoing responsibility of the network management. Training is usually conducted through in-class or one-on-one instruction and through the documentation and training materials provided.

11-33 COST MANAGEMENT

11-34 Sources of Costs The total cost of ownership (TCO) is a measure of how much it costs per year to keep one computer operating. Many studies for TCO indicate it can cost up to five time the value of the computer to keep it operational. Although TCO has been widely accepted, many organizations disagree with the practice of including user “waste” time in the measure and prefer to focus on costing methods that examine only the direct costs of operating the computer.

11-35 Sources of Costs Since the largest cost item is personnel time, the primary focus of cost management lies in designing networks and developing policies to reduce personnel time, not reduce hardware costs. Network managers often it difficult to manage their budgets because network grow so rapidly. Many organizations have implemented charge-back policies for users of WANs and mainframe-based network.

11-36 Sources of costs

11-37 Reducing Costs Five steps to reduce network costs u Develop standard hardware and software configurations for client computers and servers. u Automate as much of the network management function as possible by deploying a solid set of network management tools. u Reduce the costs of installing new hardware and software by working with vendors. u Centralize help desks. u Move to thin client architectures.

11-38 NETWORK MANAGEMENT TOOLS

11-39 Network Management Software Network management software is designed to provide automated support for some or all of the network management functions. There are three fundamentally different types of network management software: Device management software System management software Application management software

11-40 Network Management Software

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11-43 Network Management Standards One major problem is ensuring that hardware devices from different vendors can understand and respond to the messages sent by the network management software of other vendors. The two most commonly used network management protocols are: Simple Network Management Protocol (SNMP) Common Management Interface Protocol (CMIP)

11-44 Network Management Hardware Testing is divided into: analog testing - the analog side of the modem digital testing - digital communications circuits protocol testing - procedures, packets and messages. Testing hardware includes: Monitors and analyzers Patch panels Data recorders Handheld test sets

11-45 Network Management Hardware Breakout box - a handheld device that can be plugged into a modem’s digital side to determine voltage levels. Bit-Error Rate Tester (BERT) tests the # of bits in error divided by the total # of bits received. Block-Error Rate Tester(BKERT) - calculates the number of received blocks that contain at least one bit error divided by the total # of blocks received. Fiber Identifier - locates a particular nonworking fiber without interrupting service on a fiber optic network.

11-46 Network Management Hardware Cable analyzer - checks LAN cabling for signal continuity, pulse distortion, parity, conductivity, connectivity, polarity reversals, and excessive noise on the data stream. Protocol Analyzer - decodes messages on the circuit to allow you to see the content of a frame or packet during its transmission. Data Line Monitor - traces network activity and response time analysis on a specific circuit, and checks the actual data.

11-47 Network Management Hardware Automated test equipment - hardware and specialized software packages to perform diagnostic testing, polling, statistics gathering, protocol emulation, measurement of bandwidth efficiency, self diagnosis, analog and digital circuit testing, testing of centralized and remote switches, and automatic restart and recovery in case of disaster.

11-48 End of Chapter 11