Part 2 What is MAIPN good for?

Click here for Part 1 — About MAIPN

Diagram of MAN with nodes on radio towers and tall buildings
Figure 1 MAIPN Metropolitan Area Network

What is MAIPN good for? In short, once you are connected to the MAIPN backbone, you can do anything you can do on a normal office local area network, including:

  • send and receive email with attachments to other network users
  • place phone calls using a VoIP telephone
  • store and share files on a network shared drive
  • stream video
  • access the Internet through a distant portal if your local Internet access is interrupted
  • conduct or participate in audio or video teleconferences (e.g. Zoom calls)

Of course, given the limited capacity of the microwave links that make up the MAIPN network, there are constraints on how many users can be served at the same time. Our network cannot support hundreds of users, but it can potentially support dozens of email users and telephone conversations.

One goal of MAIPN is to establish permanent links to local and state Emergency Operating Centers as well as hospitals in the served area to the MAIPN backbone. Given that the MAIPN backbone is completely independent of commercial telecommunications infrastructure and existing networks, this will potentially provide served agencies with a redundant telecommunications capability that might be able to partially offset a major telecommunications outage. Of course, the MAIPN backbone is subject to weather damage and wide-scale power outages, just as commercial telecommunications equipment is. But the independent nature of our network provides an extra layer of resiliency.

If one compares MAIPN to traditional Amateur Radio backup communications systems, our traditional radios are the ultimate in infrastructure-independent communications. However, the amount of traffic that can be carried over a two-way radio channel is limited to how fast one person at a time can talk! That’s much better than no communications at all, but far less than we are accustomed to in our daily activities, let alone the demands of a large disaster. MAIPN takes advantage of new technology that provides modest bandwidth for the Internet age with relatively simple, inexpensive equipment.

Another potential use for MAIPN is to rapidly project broadband data service into an arbitrary field location. Imagine a train derailment in a rural location well-removed from commercial telecom service. By establishing a microwave link from the disaster scene or staging area to a nearby hilltop, and from there to a MAIPN backbone node, broadband service could quickly be provided to that isolated location.

It might not even be necessary to establish a connection to the MAIPN backbone. MAIPN volunteers could provide a microwave link to any nearby location where an Internet connection is available, such as a farmhouse served by Comcast or a traffic intersection with a traffic camera.

MAIPN volunteers have conducted exercises to see how feasible it is to deploy broadband service to an arbitrary location. We have found that it can be very challenging to do so, but we have enjoyed success in a number of these exercises, and developed skills that make this a potential solution in at least some cases. As we add nodes to our existing network, we will be able to reach more locations.

On a more prosaic level, the MAIPN network is currently being used by digital mode repeaters at two different locations to gain access to the internet. This internet access supports DMR, P25, and Echolink services on the connected repeaters, and also provides a way for the repeater operators to perform remote management of the repeaters and associated equipment at the two sites. We are also providing internet backhaul to two Winlink VHF RMS Gateway stations that are collocated with MAIPN network nodes.

We have an Asterisk VoIP switch operating on the network backbone, with extension telephones installed at several of our network locations. Normally, this is used to provide intercom capability between sites, but in an emergency, we can patch the switch into the public switched telephone network. When we do that, a user at any extension can dial 9 for an outside line to place a phone call to any U. S. number.

Click here for Part 3 — Technical overview of the network