Wireless Network Management Mohammad Rasol Saidat

Agenda Network Management and its architecture SNMP Protocol System Architecture Fault management system Performance Manager MIBs Tools can be used in Wireless managements

Network Management Network management is a service that employs a variety of tools, applications, and devices to assist human network managers in monitoring and maintaining networks.  Configuration Management  Performance Management  Fault Management  Accounting Management  Security Management

Network Management Architecture

Network Management Configuration Management  Monitors the Network and system configuration information  Each network device has a variety of version information associated with it  TCP/IP software Version 2.0  SNMP software Version 3.1 Performance Management  Measures various aspects and make them available so that the inter network performance can be maintained.

Network Management Fault Management  Detects network problems log them and automatically fix them to keep the network running safely. Accounting Management  Measures Network Utilization parameters. Security Management  Controls unauthorized access to the network resources so that the network is not sabotaged.

The Network Management Should meet the following : The management interface must be... The management mechanism must be... Standardized Extendible Portable Inexpensive Implemented as software only

SNMP is a tool (protocol) that allows for remote and local management of items on the network including Servers, Workstations, Routers, Switches, Mobile stations, Base stations and other managed devices. Comprised of agents and managers Agent - process running on each managed node collecting information about the device it is running on. Manager - process running on a management workstation that requests information about devices on the network. What is the SNMP ?

Advantages of using SNMP Standardized universally supported extendible portable allows distributed management access lightweight protocol

Ports & UDP SNMP uses User Datagram Protocol (UDP) as the transport mechanism for SNMP messages UDP Port SNMP Messages UDP Port SNMP Trap Messages Like FTP, SNMP uses two well-known ports to operate: Ethernet Frame IP Packet UDP Datagram SNMP Message CRC

SNMP network management is based on three parts: The Three Parts of SNMP Rules specifying the format used to define objects managed on the network that the SNMP protocol accesses A map of the hierarchical order of all managed objects and how they are accessed Defines format of messages exchanged by management systems and agents. Specifies the Get, GetNext, Set, and Trap operations

Nodes Types Items in an SNMP Network are called nodes. There are different types of nodes. Typically runs an agent process that services requests from a management node Typically a workstation running some network management & monitoring software A node may not support SNMP, but may be manageable by SNMP through a proxy agent running on another machine Nodes can be both managed nodes and a management node at the same time (typically this is the case, since you want to be able to manage the workstation that your management application is running on.)

Four Basic Operations Get GetNext Set Trap Retrieves the value of a MIB variable stored on the agent machine (integer, string, or address of another MIB variable) Retrieves the next value of the next lexical MIB variable Changes the value of a MIB variable An unsolicited notification sent by an agent to a management application (typically a notification of something unexpected, like an error)

Wireless Network A wireless network is a computer network in which communication between machines occurs over a wireless link. Cellular networks Orange Jordan, Zain and Umniah. Satellite networks Iridium, NileSAT, etc. Battlefield networks Communication between Defense departs., soldiers, etc. Wireless Local Area Networks (LAN) IEEE

IEEE Overview Adopted in The Connectionless IEEE local networks define 2 topologies Infrastructure Network – connected through AP’s Ad-Hoc Network – peer-to-peer communication

Overview, Architecture Infrastructure Network

Overview, Architecture Ad-Hoc Network

Steps 1. Discovery of New Access Point 2. Transfer of PIN 3. Registration Protocol runs as EAP (Authentication) method 4. New AP Settings sent Access Point Registrar Transfer of PIN Registration Protocol New AP Settings Discovery Securely Connected Setting Up a New Wireless Network

Setting Up a New Member Device Enrollee Access Point Registrar UPnP Discovery UPnP Event Start (Authentic ation) EAP New Enrollee Notification Reads PIN from Enrollee Reads PIN from Enrollee Registration Protocol Continues Securely Connected

Signal Monitoring System for managing the wireless Network  To Manage the wireless networks system a signal monitoring system can be used.  This system does not interfere with the regular network operations.  Listens  Measures  Sends alarms

System Architecture NETWORK MANAGEMENT CENTER PERFORMANCE MANAGER Cellular Network Scanning Receivers

Implementation of the Management System  There 2 high level versions of implementation  Centralized Performance Manager  Distributed Performance Manager

FAULT MANAGEMENT SYSYTEM  THE PERFORMANCE MANAGER  THE NETWORK MANAGEMENT CENTER

The Performance Manager  The Scanner Interface  The Measurement Database  The Alarms Generator  The NMC Interface

Performance Manager Structure MEASUREMENT DATABASE ALARM GENERATOR SCANNER INTERFACE NMC INTERFACE

The Performance Manager The Scanner Interface  Two Modes  Transmit Mode – Downloads list of scanning channel identifiers and sends them to the associated scanner for measurements.  Receive Mode – collects the measured data from the scanners according to the list of channel identifiers previously sent for measurement.

The Performance Manager The Measurement Database  It is a Relational Database that stores the received data in the scanner interface (receive mode)  It consists of tables

The Performance Manager The Alarm Generator  If correlated results indicate poor coverage, the alarm generator generates an alarm to NMC and sends via NMC interface in performance manager structure.

The Performance Manager The Alarm Generator  Alarm contains the following information  BSC identifier  BST identifier  Faulty channel identifier  Alarm code  Alarm description  Scanner identifier  Scanner location  Timestamp  Alarm severity

The Performance Manager The NMC Interface  It enables communication between the performance manager and the Network Management center  It has two modes  Transmit – sends alarm from alarm generator to NMC  Receive – It receives the channel identifiers for each base station and forwards the list via scanner interface

The Network Management Center  The Performance Manager Interface  The Management Information Base  The Graphical User Interface

The Network Management Center  The Performance Manager Interface  Two modes  Transmit mode- Transmits the list of channels that are allocated for each BTS to NMC interface in Performance Manager  Receive mode – Receives alarm from the performance manager and stores them into MIB

The Network Management Center The Management Information Base(MIB)  The Management Information Base is a Relational Database which stores all the information.  Each area has an Operator and a team of technicians.  Each region consists of many areas and each region is managed by supervisor and all supervisors report one super user

The MIB Structure SUPER USER SUPERVISOR1 SUPERVISOR2 SUPERVISOR3 Operater2Operater1Operater2Operater1Operater2Operater1

The MIB Organization

The Network Management Center The Graphical User Interface  NMC includes a Graphical User Interface containing a Geographic map of the network coverage area, with an overlay graphical presentation of the managed network elements and their Interconnections

Some advanced GUI interfaces in network management systems have the following features  Changing the color of the network element based on severity of the alarm  Blinking occurs when the network element has some emergency  Clicking on the network element gives the real time information about the element configuration and pending alarms The Graphical User Interface

The Graphical user interface

Examples of ManagmentTools Protocol Analyzer WhatsUp MRTG MRTG-UFFE NMS

Packet Analyzer Device that lets you see packets on the wire Our tool is a Network Associates’ Sniffer Primarily a troubleshooting tool However, by capturing the data on a connection (e.g. uplink) over time you can collect key network statistics Flaw: It only does ONE connection at a time Protocol Analyzer measures packets

Whats up Monitors network devices (e.g. switches & routers) servers & server applications uses ICMP (ping) and TCP/IP ports If device responds server is deemed to be up Flaw: Just because the web server port opens on port 80 this does not necessarily mean the web server is working properly; it just means that the web server is up WhatsUp measures availability Uses drill down method (example to follow)

Whats up

MRTG MRTG = Multi Router Traffic Grapher Monitors bits in and out of a network device (eg. Switch port, router port, NIC card) Using SNMP it queries the switch for port activity once every five minutes Keeps daily, weekly monthly and yearly statistics on that port Flaw 1: If there is a lot of usage then the device(s) attached to the port are running well. If usage is low then ???? Flaw 2: It monitors amount of bits not the number of packets. If you had a Denial of Service attack with a large number of small packets MRTG would not indicate a problem MRTG measures bandwidth Like WhatsUp, MRTG uses drill down method

MRTG UFFE MRTG-UFFE = MRTG’s User Friendly Front End Add on to MRTG Homegrown utility that documents the important (special, unusual, busy) connections on campus Hyperlinks to MRTG MRTG-UFFE measures connections

Conclusion  The signal Monitoring system improves the reliability and the quality of service of a wireless network by efficient failure detection and location.  It also improves the Overall network coverage and availability of network resources.

References  Jelena Vucetic, paul Kline: “signal Monitoring system”, IEEE Dynamic Telecommunications 1998  S. M. Dauber: “Finding Fault”, BYTE Magazine, McGraw-Hill, Inc. New York, NY, March 1991  0. Wolfson, S. Sengupta, Y. Yemini: “Managing Communication Networks by Monitoring Databases”, IEEE Transactions on Software Engineering m Vol. 17, No. 9, September 1991  L. Feldkhun: “Integrated Network Management Systems”, Proceedings First International Symposium on Integrated Network Management, 1989  M2YzO/Wireless_Network_Management_SANDEEP_powerpoint_ppt_pr esentation

Questions  What are the Advantages of the Fault Management system? Ans: improves the reliability and the quality of service of a wireless network.  What are the system design Considerations to be considered to while designing the Monitoring management system? Ans: No. of Scanners and the locations where they should be placed. For the cost to be minimum the no. of scanners should be less.  How does this fault management system improve reliability and Network coverage? Ans: Efficient failure detection and also the location of the failure.