NATIONAL TRAFFIC SYSTEM MESSAGE ROUTING by VA3BZ

NATIONAL TRAFFIC SYSTEM MESSAGE ROUTING

NTS message routing is one of those things which seems like a piece of cake when you understand it but which is very difficult to explain to anyone else. It's something like knowing your way around a big city very well – one can easily zip around all over the place using the best routes, which often depend upon the time of day, with the greatest of ease. But it becomes very complicated if one has to explain the whole thing to a newcomer. About the best one can do as a beginning is to direct one to follow a particular route to get to a particular destination without explaining any of the reasons for the choice of that route. Eventually, with practice, the newcomer learns his ways.

NTS routing is somewhat similar to commercial airline routing. It would be hopelessly impractical to have airline passenger routes to and from every destination that anyone might want to fly. For example, there are no direct scheduled passenger routes between Windsor and Sarnia or London or Kitchener or Kingston. Instead, if one wishes to fly from Windsor to London, one must first fly to Toronto and then fly from Toronto to London. Toronto is a central hub from which flights are scheduled to fly to almost almost any location in Ontario.

The NTS is divided into three layers. The lowest layer includes the section nets, of which there is now only one in Ontario, the OPN, although there are still several in Michigan. The next layer includes the regional nets. In the USA, the regions correspond very closely to the call areas. For example, the 8th region includes MI, OH and WV, and its regional net is known as the 8RN net. The top layer consists of the area nets of which there are three, the EAN, CAN and PAN. The EAN is the Eastern Area Net and is the traffic hub for the 1RN, 2RN, 3RN, 4RN and 8RN nets. A similar situation exists for the Central and Pacific area nets. Traffic between the areas is handled by the TCC, which means the transcontinental corps. Proper traffic routing requires that traffic is moved from section nets to region nets and then to area nets from which it goes back to region nets and then to section nets. There are designated operators at all levels to both send and receive traffic. This is an extraordinarily efficient scheme which assures that messages are moved swiftly throughout the system.

To better understand how it works, let me use the 8th region as an example. Any traffic originated in Michigan and destined for Michigan is, of course, handled within Michigan by their section nets. Any traffic destined to go outside Michigan is carried to an 8th region net by a liaison operator. Such traffic as might be destined for either OH or WV is relayed to the liaisons from OH and WV within that net; everything else is carried by another liaison to the EAN where it is relayed to appropriate stations there. That takes care of the routing of all traffic destined for the USA and Canada. Traffic received on the EAN by the 8th region receive operator is carried back to an 8th region net and follows the same paths, but in the opposite direction, as the sent traffic had followed. For this whole scheme to work smoothly, there has to be a full compliment of both receive and send operators at all levels. Often, when the expected traffic is light or the operator is good enough, a single operator will be liaison for both send and receive.

All of the regional and area nets have numerous sessions, both voice and CW, throughout the day. Some regions and areas have more than others. Whatever, the net times are arranged to maximize the flow of traffic through the system and minimize the time it takes to get messages through the system.

Up until only recently there was the Eastern Canada Net (ECN) which was the regional net for Ontario, Quebec and the Maritimes. It was shut down and Ontario and the Maritimes are now included in the 2nd region which formerly consisted of only the states of New York and New Jersey. Thus, traffic from Ontario is now carried to the 2RN net rather than as formerly to ECN.

Efficient as is the organization of the NTS, it can be readily appreciated that some traffic can follow a very long roundabout route to get from where it originates to its destination.
As an example, the NTS route for traffic originating in Detroit and destined for Windsor is through a MI net, then to an 8RN net, then to the EAN, then to a 2RN net and finally to the OPN. Many who don't understand the system suppose that it would be much more appropriate to simply move the traffic across the Detroit river directly and bypass normal NTS routing. There are many reasons why that should not be done:

1.   Other than once only relays of convenience, it requires that some kind of a net be established so that the route is available reliably.

2.   When the NTS system is working normally, a message originating anywhere in the system reaches its NTS destination in only one day. What need is there for more speed than that? It is, of course, acceptable to move emergency traffic by any means available.

3.   There are designated send and receive operators everywhere throughout the NTS. Whenever short circuit routes are used to relay traffic, NTS operators are starved of traffic. It's not uncommon for a receive operator to go to a net and find there is nothing there for him to receive. That may have happened because some traffic flowed through a short circuit somewhere.

4.   There is keen competition among some NTS operators to achieve the highest message count for a given month or even to do better than some other operator in a section or region. Whenever someone uses short circuit routes, there is less traffic for the normal routes and some operators end up with smaller numbers than they ordinarily would. This situation is especially irksome if one of the high scorers himself is using short circuit routes.

R E Heath, VA3BZ
2010 May 14