Why do we have nets?
A major strength of Amateur radio is the ability to share information in a group setting where one person talks and the others monitor and copy traffic. This ability gives flexibility in an emergency or routine situation to relay information. However, if the traffic is not organized and following a set of protocols the positive aspects of the system give way to failure with chaos and disorganization.
During an emergency communication situation, a high volume of disorganized messages can quickly turn to an overloaded communication system into a disaster of its own. To prevent this amateur radio has a set of protocols call a "network" or short a "net" The mission of a net is to move traffic as efficiently and accurately as possible.
The net manager is the person in charge of a net, but is most often not the person running the net, that is reserved to the Net Control Station or NCS, who may be assisted by an Assistant Net Control Station or ANCS. These positions will rotate through personnel as shifts change. The net manager may be in charge of several nets.
The role of the NCS is to direct the net, control traffic, and determine priority traffic, and provide organization to what is normally a chaotic event. The NCS is not only responsible for the direction of traffic but also responsible for the health and welfare of the operators in the net. This is why it is important to not leave the net until permission to do so. There may be net liaisons who has the responsibility to move traffic from one net to another. Ideally, the NCS has assistants and scribes keeping coordinated information.
Type of Nets
Open informal nets - During an emergency, there is minimal central control by a Net Control Station. This net allows station to station contact. This is not a rag chew frequency but a chance to coordinate traffic that only relates to two stations. If you do not have the ability to monitor both the primary net and the informal net you will need to ask permission of NCS to temporarily move frequency. Then when done, move back to the primary net and notify net control you are back on frequency. Inversely, if you have station to station traffic you can request net control to ask the other station to move to the informal net to pass traffic.
Directed Formal Nets - A directed emergency net is created whenever large number of stations are participating. Directed nets are preferable since the traffic can be coordinated and prioritized. In a directed net stations cannot "break into" or interrupt the net. They listen and wait to ask permission to pass traffic. Directed nets may use "tactical" call signs versus FCC issued call signs to aid in shift changes.
Traffic Net - Handles formatted written messages between served agency locations or between other nets. Messages to or from outside the immediate area may be handled by a Section-level net, and depending on the distances involved, Regional Nets and Area Nets may be employed to get traffic out to functioning phone and internet locations. These nets may be voice or digital as needed.
Resource Net - This net is used for new operators to check in and await assignment, or asking for relief or reassignment. A resource net may also be used to locate needed equipment, or operators with specific skills. Several different resource nets may be utilized depending on the size of the event.
Tactical Net - There may be one or many of these nets. These nets handle the primary on-site emergency communication between served agencies. There may be "sub nets" created to handle specific types of traffic during high volume emergency situations.
Information Net - An information net might be used to make regular announcements, disseminate official bulletins or answer general questions.
Health and Welfare Nets - These nets usually handle messages between concerned friends, families, and persons in the disaster area. Most H&W nets will be on HF bands, but local "feeder" UHF & VHF nets may be needed.
Organization of Nets
You may ask why there is no formal organization of nets prepared for an emergency situation. The answer is until the emergency is known, the needed nets are then known and can be organized. As the situation develops, new nets can be created, and as the situation resolves itself nets can be closed or consolidated.