Monitoring Tool , SNMP

       Monitorting Tools such as HP Openview, IBM Tivoli Monitoring Software,
       Empirix Onesight, Solarwinds, nagious, MRTG etc are used to monitori
       the health of the all the elements in an IT infrastructure that includes
       everting router, network traffic, switches, servers,gateway etc , and view /
       store the data in central space that is used for Monitoring/ reviewing etc.
       The innerworking of all this tools is same and all use the SNMP
       (Simple Network Monitoring Protocol)
            SNMP has two major components Manager and Agents.
            SNMP defines how a manager communicates with an agent.
            It defines the format a requests that manager sends to an agent
            and the format of replies than an agent returns.
            MIB (Management Information Base) is the set of all objects
            SNMP can access. Objects in SNMP are defined with a certain
            naming scheme which assigns each object a long prefix that
            guarantees the name will be unique. Object with MIB
           name -
           Now when this object is represented in an SNMP message, each
           part is assigned an integer. OID for the above name is -
         One of the Open source tools which uses the above technology is
          MRTG ( Multi Router Traffic Grapher)
         MRTG :
         Multi Router Traffic Grapher is a tool generally used to monitor
         traffic load on network links. People also use MRTG to monitor
         things such as system Load, Login sessions disk space etc. 
         MRTG generates HTML pages containing PNG images which
         provides visual representation of the item monitored. MRTG
         consists of a Perl Script which uses SNMP to read monitorig item
         counters and a fast C program which logs the gathered data and
         creates graphs representing the data received. This graphs are
         embedded into webpages which can be viewed from any modern