device monitoring

Thanks Brian for the link, anyone else know of anything similar???

Have you attempted to Google for the keywords?

I got hundreds of thousands of hits in less than a second.

I did yes, but everything seems very vague. Im looking for info from anybody who has done anything like this before, recommendations, appropriatelinks etc. See below for my plan. For my project il prob need to tie in about 4 technologies/protocols together when working with it. SNMP Simple Network Management Protocol is a platform independant protocol used to transmit device status information across a network. How this info is picked-up, translated and finally used/presented is the trick. I will try to enable SNMP on a few machines so I can see what is being broadcast. It runs as a service and can be installed on any machine. A few applications exist, which pull in the SNMP data and make sense of it. All I need is an IP Address and a SNMP enabled box. Typically a scan every 5mins collects the data and creates trends which can be used to access performance and even identify problems on CPU/Memory usage/Harddisk usage/etc. When collecting the data, I then plan to use it in graphs to be stored to be used for historical reference. That is a basic spec of what I plan to do, any more recommendations??

SNMP as a protocol is simple. What is not simple is the coding of the data in the packets.

The protocol calls for a minimum data store called a MIB (Management Information Block), and it's far too extensive for a simple monitoring job if the device is not a network node.

The MIB components transferred over the UDP packets of a SNMP connection are coded in a special format called ASN.1 which is also not-so-simple.

The W Richard Stevens' book on TCP/IP protocols (TCP/IP Illustrated, Volume 1) describes the SNMP transfer protocol pretty well, but the MIB and ASN.1 are left with a cursory glipmpse.

There is a book of SNMP in the O'Reilly animal series, but it's mostly targeted for using ready SNMP tools for network monitoring.

HTH

In most cases, on a PC or workstation, SNMP tends to work in a passive way rather like a web server. To obtain information from an SNMP enabled device, you need a MIB browser.

Think of SNMP as many web servers all being viewed by a single browser.

An SNMP agent stores data in the system being monitored in what is called a MIB table. When a request for data comes in from the outside world, it is also in the format of a MIB, but the MIB is empty. The agent fills the MIB with the data that it has gathered and sends it back to the source of the request. At least that is the simple explanation. There is a bit more shifting of data being done.

SNMP also has alarms, which have to be subscribed to. So a node that is interested in a particular alarm, tells the agent. When the alarm occurs, the agent replied to all the alarm requests. This is rather like push from a web server.

If the device is 'intelligent' enough to run an SNMP agent then it is possible it could use CORBA (look up "What is CORBA" on Google). You might want to add CORBA to your list.

You could of course consider XML and HTTP as an alternative to SNMP (half the embedded systems world seems be doing just that).

Hope this helps.