Transcript Nineth-Part-Wireless_Network_Management_Saidat

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.
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Configuration Management
Performance Management
Fault Management
Accounting Management
Security Management
Network Management Architecture
Network Management
Configuration Management
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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
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SNMP software
Version 3.1
Performance Management
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Measures various aspects and make them available so
that the inter network performance can be maintained.
Network Management
Fault Management
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Detects network problems log them and automatically fix
them to keep the network running safely.
Accounting Management
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Measures Network Utilization parameters.
Security Management
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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...
•Standardized
•Extendible
•Portable
The management mechanism must be...
•Inexpensive
•Implemented as software only
What is the SNMP ?
• 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.
Advantages of using SNMP
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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
Ethernet
Frame
IP
Packet
UDP
Datagram
SNMP Message
CRC
•Like FTP, SNMP uses two well-known ports to operate:
•UDP Port 161 - SNMP Messages
•UDP Port 162 - SNMP Trap Messages
The Three Parts of SNMP
SNMP network management is based on three parts:
•Defines format of messages exchanged by management systems and agents.
•Specifies the Get, GetNext, Set, and Trap operations
•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
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
Retrieves the value of a MIB variable stored on the agent machine
(integer, string, or address of another MIB variable)
•GetNext
Retrieves the next value of the next lexical MIB variable
•Set
Changes the value of a MIB variable
•Trap
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.
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Cellular networks
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Satellite networks
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Iridium, NileSAT, etc.
Battlefield networks
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Orange Jordan, Zain and Umniah.
Communication between Defense departs., soldiers, etc.
Wireless Local Area Networks (LAN)
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IEEE 802.11
IEEE 802.11 Overview
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Adopted in 1997.
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The Connectionless IEEE 802.11 local networks
define 2 topologies
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Infrastructure Network – connected through AP’s
Ad-Hoc Network – peer-to-peer communication
Overview, 802.11 Architecture
Infrastructure Network
Overview, 802.11 Architecture
Ad-Hoc Network
Setting Up a New Wireless
Network
Access Point
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2.
Discovery
Transfer of PIN
Registration
Securely
Protocol
New
AP
Connected
Settings
Registrar
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4.
Steps
Discovery of New
Access Point
Transfer of PIN
Registration Protocol
runs as EAP (Authentication)
method
New AP Settings sent
Setting Up a New Member Device
Access Point
Registration
Protocol Continues
Securely Connected
DiscoveryStart
(Authentic
ation) EAP
UPnP
Event UPnP
Reads PIN from
Enrollee
New
Enrollee
Notification
Registrar
Enrollee
Signal Monitoring System for
managing the wireless Network
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To Manage the wireless networks system a signal
monitoring system can be used.
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This system does not interfere with the regular
network operations.
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Listens
Measures
Sends alarms
System Architecture
NETWORK
MANAGEMENT CENTER
Cellular Network
PERFORMANCE
MANAGER
Scanning Receivers
Implementation of the
Management System
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There 2 high level versions of implementation
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Centralized Performance Manager
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Distributed Performance Manager
FAULT MANAGEMENT
SYSYTEM
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THE PERFORMANCE MANAGER
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THE NETWORK MANAGEMENT CENTER
The Performance Manager
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The Scanner Interface
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The Measurement Database
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The Alarms Generator
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The NMC Interface
Performance Manager
Structure
MEASUREMENT
DATABASE
SCANNER
INTERFACE
ALARM
GENERATOR
NMC
INTERFACE
The Performance Manager
The Scanner Interface
 Two Modes
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Transmit Mode – Downloads list of scanning channel
identifiers and sends them to the associated scanner for
measurements.
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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
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It is a Relational Database that stores the
received data in the scanner interface
(receive mode)
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It consists of tables
The Performance Manager
The Alarm Generator
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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
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Alarm contains the following information
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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
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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
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The Performance Manager Interface
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The Management Information Base
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The Graphical User Interface
The Network Management Center
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The Performance Manager Interface
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Two modes
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Transmit mode- Transmits the list of channels
that are allocated for each BTS to NMC interface
in Performance Manager
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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
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The MIB Structure
SUPER USER
SUPERVISOR1
Operater1
Operater2
SUPERVISOR2
Operater1
Operater2
SUPERVISOR3
Operater1
Operater2
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
The Graphical User Interface
Some advanced GUI interfaces in
network management systems have
the following features
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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
Examples of ManagmentTools
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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
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The signal Monitoring system improves the
reliability and the quality of service of a
wireless network by efficient failure detection
and location.
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It also improves the Overall network coverage
and availability of network resources.
References
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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
http://www.powershow.com/view/1cfe58M2YzO/Wireless_Network_Management_SANDEEP_powerpoint_ppt_pr
esentation
Questions
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What are the Advantages of the Fault Management system?
Ans: improves the reliability and the quality of service of a wireless
network.
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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.
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How does this fault management system improve reliability and
Network coverage?
Ans: Efficient failure detection and also the location of the failure.