NEXT includes the following features:

• Real-time monitoring of the wireless links.
• Automatic network nodes discovery.
• Event creation.

Architecture

The NEXT monitoring system consists of several subsystems, each performing a specific function:

• Polling subsystem - periodically polls the network nodes to obtain their parameters's values.
• "SNMP Trap" processing subsystem - provides "SNMP Trap" reception, preliminary processing and transmission to the polling subsystem.
• Event creation subsystem - monitors the change in the parameter values provided by the polling subsystem, and creates the events according to a certain set of rules.
• Device discovery subsystem - performs automatic detection and addition of the network nodes.
• Web GUI - graphical interface that allows the NEXT operating engineer to manage the monitoring system.
• Storage subsystem - the database.

Polling subsystem 

The main NEXT subsystem periodically polling the network nodes and obtaining their parameters's values.

The subsystem is working constantly. It distributes all the necessary polling in order to perform the entire network polling during a 5 minutes interval, so NEXT prevents peak loads on the wireless network:

• The time required for sequential polling of all the network nodes is determined based on the number of network nodes. If there are too many devices, a situation may occur when the time available to poll each node is less than the minimum required time. In this case, the network nodes will be grouped, and the survey will be conducted in parallel for all the network nodes of each group.
• Checks if the network nodes are ready for the survey. The nodes that have the polling completed in a previous cycle will be polled first. The nodes with incomplete polling in the previous cycle will be polled last.
• If there are network nodes for which the polling began in the previous cycle and did not complete during the current 5 minutes period, then these nodes will be queued for polling in the next cycle.
• All the data received from the nodes during the polling are placed in the storage subsystem.

Determining the link between devices

"SNMP Trap" processing subsystem 

The parameters of the network nodes can also be obtained using the SNMP Trap notification mechanism. Usually, a node using this mechanism will notify NEXT about a change in the parameters's values that are critical for the operation of the device and/or of the wireless link, for example, when the connectivity is lost between the devices etc.

While the polling subsystem is an active component, the SNMP Trap processing subsystem is passive. It is always ready to receive Traps from network nodes. After receiving the notifications, the subsystem proceeds with their unscheduled processing, allowing for a timely response to changes, without waiting for the completion of the polling cycle.

Event subsystem 

The subsystem's task is to create an event based on the rules set by the NEXT administrator.

The event subsystem's operation begins after the information received about the changes in the network nodes's parameters obtained through the polling subsystem or through the "SNMP Trap" processing subsystem is placed in the storage subsystem. This subsystem verifies the match between the rules set for the event and the received parameters. If the condition specified in any rule is met, an event is generated, and it can be viewed in the web interface of the monitoring system.

Discovery subsystem 

The subsystem performs the automatic search and addition of the network nodes. After a device was added manually, the discovery subsystem performs the following functions:

• Detects any neighboring device of the newly added node that is in the same MINT area and has a connection already established, but has not yet been added to NEXT.
• Generates a polling task for the neighboring network nodes using the SNMP authentication data specified by the NEXT engineer for this device.
• The polling subsystem performs an unscheduled polling of the neighboring device. If the specified authentication data is correct, then the neighboring device will be added automatically. If the data does not match, a new request will be generated to the polling subsystem with the authentication data that was specified for other devices previously added to NEXT. The requests will be repeated until any authentication data matches or it runs out of available authentication data.
• After adding the detected network node, a search for neighboring nodes will be also carried out. This process ends when the neighbors of all the previously added nodes have been discovered and polled. The network nodes without authentication data matching will not be added and attempts to add them will carried out in the future.

An important feature of the subsystem is that it performs the search only within a single MINT area. If there are several MINT areas in a wireless network, then at least one node from each area must be added in order to detect the other network nodes.

Notification subsystem

The subsystem is designed to send notifications to the users of the monitoring system.

Web GUI 

For the NEXT monitoring system management, a graphical web interface is used. The Web GUI interacts with all the subsystems.

The Web GUI works properly with the following web browsers:

• Chrome 81 and older, and its derived browsers;
• Firefox 75 and older, and its derived browsers.

The recommended minimum screen resolution is 1600×900.

Storage subsystem 

The subsystem provides data storage and quick access to the information for the web GUI and subsequently for the engineers operating the NEXT system.