75 years ago, this was a decisive element of the Allied campaign from D-day through the crossing of the Rhine. Signal Corp units carried cages of pigeons homed to coops in London for message transmission back to Allied High Commond to avoid signal interception.
Once a pigeon is born, it's homed to a coop... Route persistence with absolutely no way to corrupt the routing table. Pigeon retain their ability to find their home coop even if they've been away from it for years.
The signal transmission is virtually unsniffable, the only way to intercept the message is to destroy the transport. Homing pigeons in flight to their home coop are NOT like the feral pigeons you see in a city park... They are 50mph missles that are very hard to track and eliminate. Using high quality bred transports, like Janssens or Husken Van Riels would increase speed, distance and reliability.
Each hub could support a inward star topology of 1 to 3000 miles in diameter. Smaller diameter stars would reduce data loss and increase speed marginally. With their many to one topology, they can be used in multicast mode if several birds from different home coops are released from the same location.
Overall data losses would be low, approximately 2% to 5% of all data packages sent would be lost. Raptors and inclement weather would be the leading causes for data loss.
Pigeons have a very low operating cost, feed and water and a place to roost... Significantly lower than any petro based transport like station wagon or plane. They also have a service lifespan on 5 to 10 years.
Now add to that the Green element, pigeons have a minuscule carbon footprint, they eat grain that can be cultivated locally and their waste makes excellent fertilizer to sustain grain production. You can't forget the fact that they are a source of meat once their usefulness as a carrier expires.
