To use the example app:

Push two differently named instances of the app

cd ~/workspace/cf-networking-release/src/example-apps/proxy
cf push appA
cf push appB

See that they are reachable and what their IPs are

curl appa.<system-domain>
curl appb.<system-domain>

See that proxying from A to B works over both the router and overlay

curl appa.<system-domain>/proxy/appb.<system-domain>
curl appa.<system-domain>/proxy/<overlay-ip-of-appB>:8080