Test NextHopFaceId tag and LP field

Topology

B--A--C

Steps

1. Start NFD on A, B, and C.
2. On A, create routes for prefix ndn:/P toward B and C. The cost toward B is lower than the cost toward C.
3. On B, start ndn-traffic-server on ndn:/P, serving payload "BBBBBBBB".
4. On C, start ndn-traffic-server on ndn:/P, serving payload "CCCCCCCC".
5. On A, execute a consumer to enable local fields and then express an Interest for ndn:/P/1, without NextHopFaceId tag. Expect Data with payload "BBBBBBBB".
6. On A, execute a consumer to enable local fields and then express an Interest for ndn:/P/2, with NextHopFaceId=faceB. Expect Data with payload "BBBBBBBB".
7. On A, execute a consumer to enable local fields and then express an Interest for ndn:/P/3, with NextHopFaceId=faceC. Expect Data with payload "CCCCCCCC".
8. On A, execute a consumer to enable local fields and then express an Interest for ndn:/P/4, with NextHopFaceId=null-face. Expect either timeout or Nack.
9. On A, execute a consumer to disable local fields and then express an Interest for ndn:/P/5, with NextHopFaceId=faceC. Expect either timeout or Data with payload "BBBBBBBB".