Computer networks are widely used to provide increased computing power, sharing of resources and communication between users. Communication networks, such as the Internet and corporate intranets, have become the chosen form of information distribution in the workplace, as well as, the home. Computer networks are a driving force in increasing workplace productivity by allowing resources to be shared efficiently among multiple users and allowing alternate or backup resources to be used when other resources fail or become congested with traffic. Networks may include a number of computer devices within a room, building or site that are interconnected by a high speed local data link such as local area network (LAN), token ring, Ethernet, or the like. A local area network (LAN) typically comprises a plurality of computers, computer systems, workstations and other electronic devices connected together by a common media such as twisted pair or coaxial cable or fibre optic cable. Data can be communicated between devices on the network by means of data packets in accordance a predefined protocol. Local networks in different locations may be interconnected by techniques such as packet switching, microwave links and satellite links to form a world-wide network. A network may include several hundred or more interconnected devices. With the proliferation of high performance computer workstations in virtually every workplace and the increased demand for interconnectivity, computer networks have experienced corresponding growth. In computer communications, a set of computer networks which are possibly dissimilar from one another are joined together by gateways. Gateways provide data transfer and conversion of messages from the sending network to the protocols and data type utilized by the receiving network. Gateways convert information to a form compatible with the protocols utilized by other networks for transport and delivery. There are a number of available topologies for computer networks of nodes. A computer network may be highly centralized, having a mainframe computer that is accessed by a number of user computers, such as desktop computersIn a distributed network, intelligence and processing power are distributed among a number of network nodes, typically with client workstations communicating with distributed servers.

As the size of networks increases and as organizations become more reliant on such networks, the importance of effective network management tools also grows. Along with data transfer efficiency, critical network management functions such as performance monitoring may be compromised by increasing demand for bandwidth and a shift to more data-driven computing. Networks of networks are becoming a more common part of the networking environment leading to ever increasing degrees of complexity for individual network servers to manage. For example, with this increased access to computers worldwide, hacking and unauthorized access to networks has become an increasingly serious problem. Hackers or other persons attempt to gain access to networks and computers to secure information and/or perform some prank or mischief. A person may try to gain unauthorized access to a network to obtain information, such as credit card numbers, confidential technology, or business information. One known system for protecting a network against attacks is a firewall at the gateway of the network. The firewall serves to prevent communications of the types prescribed by the network administrator from occurring between the network and external networks. Management of the network involves configuration of software available on the machines or for a user in the network, coordination of access to shared resources and implementation of security measures. The communication traffic on the computer network is monitored to ensure that the system is appropriately configured to reduce security risks and to improve efficiency. Most computer networks are configured by setting various configuration parameters for each machine or user in the computer network. Configuration parameters may include data indicating which software is available on each machine or for each user of the computer network. With most computer networks, configuration parameters are established and maintained by an individual, often called a network or system administrator. With the need to access information from such networks increasing, so to is the need to provide a means for monitoring the information distributed by such communication networks. Network monitoring can provide valuable information, statistical or otherwise, to network service providers, network users or network beneficiaries. An increasing reliance on networked computer applications have generated a need for network performance monitoring tools. Such monitoring tools allow system administrators and others to observe network responses to varying loads and conditions, to identify and diagnose problems in the communications paths, and to optimize network architectures to avoid bottlenecks and other congestion-causing conditions.

Network monitoring tools are generally configured to measure and display various parameters characterizing communications between or among a plurality of network endpoints. Management of the devices in a computer network may involve the setting of various configuration parameters for each user, device, software, application, or other electronic resources installed on the devices or otherwise available via the devices. Network management systems (NMS) interact with existing hardware while minimizing the host processor time needed to perform network management tasks. The NMS is used in many modern communications networks to assist in the coordination of the activities of the network, to locate and identify faulty equipment and/or problem channels, and to optimize the performance of the network. In order to manage and monitor the network, one or more centralized network management systems are provided in which alarms and other network management information are collected in a centralized manner and in which the network monitoring personnel can control the entire network by means of work stations. In network management, the host processor or network management station is known as the network manager. A network manager is typically an end-system, such as a mainframe or workstation, assigned to perform the network managing tasks. The network manager is responsible for monitoring the operation of a number of end-systems, intermediate systems and media devices, which are known as managed nodes. Network analyzers are devices utilized to connect to communications networks, particularly packet networks, which monitor the signaling state and traffic flow of communications on the network. Data processing and storage systems that are connected to a network to perform task specific operations are known as network appliances. Because these network appliances have become important to the day-to-day operation of a network, the appliances are generally required to be fault-tolerant. Network appliances in the network are constantly monitored to identify problems and upgrade opportunities in order to help ensure the integrity and to maintain the optimal performance of a network. For example, a network administrator may monitor the throughputs of a message protector appliance in different time ranges to determine whether the appliance is performing properly and whether the appliance is being overloaded.