30-07-2012, 03:11 PM
Network Management, Security
Network Management.ppt (Size: 2.67 MB / Downloads: 50)
NETWORK MANAGEMENT
The main purpose of network management is to monitor,manage and control a network.
Network Management tasks can be characterized as follows :
QoS and performance management
Network failure management
Configuration management
Security management
Billing and accounting management.
QoS and Performance Management
A network administrator periodically monitors and analyzes routers, hosts and utilization of links and then redirect traffic flow to avoid any overloaded spots.
Certain tools are available to detect rapid changes in traffic flow
Network Failure Management
Any fault in a network such as link, host or router hardware or software outages, must be detected , located and responded to by the network.
Figure shows adapter failure at router R3 and host H37 these failures can be detected through network management.
Configuration Management
This task involves tracking all the devices under management and ensuring that all devices are connected and operate properly.
If there is an unexpected change in routing tables a network administrator wants to discover the misconfigured spot and reconfigure the network before the error affects the network substantially.
Elements of Network Management
The managing center consists of the network administrator and his/her facilities.
A managed device is the network equipment, including its software that is controlled by managing center. Example :hub,bridge,server,router,printer, modem
The network management protocol is a policy between the managing center and the managed devices.
Management Information Base (MIB)
MIB is an information storage medium that contains managed objects reflecting the current status of the network.
Objects are organized in a hierarchical manner and are identified by the abstract syntax notation one (ASN.1) object definition language.
The hierarchy of object names known as ASN.1 object identifier, is an object identifier tree in which each branch has both a name and a number.
TASK OF SNMP
SNMP transport MIB information among managing centers and agents executing on behalf of managing centers.
Second version of SNMP is SNMPv2 runs on top of more protocols and has more messaging options resulting in more effective network management.
SNMPv3 has more security options.
Domain Hijacking Attack
Once a domain name is selected it has to be registered
Various tools are available to register domain names over the Internet.
If the tools are not smart enough an invader might obtain secure information and use it to hijack the domain later.
In the Domain Hijacking Attack whenever a user enters a domain name address she/he is forced to enter the attackers website.
This can be very irritating and can cause great loss of Internet usage ability.