Patent ID: 7437453

Claim:
A method for remotely monitoring a computer network, applied in a computer network comprising a network management center and a managed device, wherein the network management center supports Simple Network Management Protocol (SNMP) and implements remote network monitoring alarm, independent objects of the managed device and attributes of the independent objects are configured in a Manage Information Base (MIB) to monitor the managed device, the method comprising: receiving, by the managed device, a Set-Request packet with an operation expression from the network management center to initiate a RMON monitoring process, wherein the operation expression is a four fundamental operation expression of arithmetic representing a combination object and comprises at least two independent objects; parsing character-string data information of the operation expression, checking whether the character-string data information satisfies syntax rules of four fundamental operations of arithmetic, and analyzing whether all independent objects in the operation expression can be sampled at the managed device; when the character-string data information does not satisfy the syntax rules of four fundamental operations of arithmetic or the independent objects cannot be sampled at the managed device, reporting to the network management center that the Set-Request is failure; when the character-string data information satisfies the syntax rules of four fundamental operations of arithmetic and all the independent objects in the operation expression can be sampled at the managed device, sampling, by the managed device, values of every independent object in the operation expression and calculating said combination object according to the operation expression, and then comparing calculated result with a preset threshold; when the calculated result exceeds the threshold, informing the network management center in real time or making a log, wherein the network management center is for implementing management for the managed device.