Very interesting. In computer networking, we deal with this same information problem, and the solution (not sending the information from the forward node back to the forward node) is referred to as Split Horizon.
Suppose that Node A can reach Network 1 directly - in one hop. So he tells his neighbor, Node B, "I can get to Network 1 in one hop!". Node B records "okay, I can get there in two hops then." The worry is that when Node A loses his connection to Network 1, he asks Node B how to get there, and Node B says "don't worry, I can get there in two hops!". This causes Node A to hand his traffic to Node B, who promptly turns it around and hands it back, and thus a loop is created. The solution, split horizon, is exactly as you say here: when you learn a piece of information, record which direction you learned it, and do not advertise that information back in that direction.
Very interesting. In computer networking, we deal with this same information problem, and the solution (not sending the information from the forward node back to the forward node) is referred to as Split Horizon.
Suppose that Node A can reach Network 1 directly - in one hop. So he tells his neighbor, Node B, "I can get to Network 1 in one hop!". Node B records "okay, I can get there in two hops then." The worry is that when Node A loses his connection to Network 1, he asks Node B how to get there, and Node B says "don't worry, I can get there in two hops!". This causes Node A to hand his traffic to Node B, who promptly turns it around and hands it back, and thus a loop is created. The solution, split horizon, is exactly as you say here: when you learn a piece of information, record which direction you learned it, and do not advertise that information back in that direction.