Traffic flows through an administered network from an off-network source and/or to an off-network destination are simulated and analyzed by selecting an ingress and/or egress node within the administered network, the ingress node capable of collecting traffic from an off-network source, and the egress node capable of routing traffic to an off-network destination. Traffic flow is mapped from the source or ingress node through the administered network to the egress node. The traffic flow may be simulated and analyzed. The ingress and/or egress nodes may be selected in a variety of ways.