Test a three-floor RPL network design

Steps

Screens captured against Contiki-NG Cooja Contiki-NG release/v4.9 c20b12cd, Cooja 4.8 (2022071901), Temurin 17.0.20.1, image sha256:b14d5afb0a2a852d9e72bbed607ead03f6ccc5f4d4dee44f0799110be2f4b609 on 2026-09-10; the tool may have moved on — the text steps are the contract.

1. 1 Step 1

   Do

   Run the CSC to 180 s. Identify root 1, paired floor routers 2–7 and leaf-only motes 8–10 in Network.

   You will see

   Root 1 is green, routers are yellow, and leaves are magenta. The leaves do not appear as parents of other nodes.

   Why it matters

   Mains and battery roles must be an explicit design decision. Leaf-only firmware prevents the battery-role motes from silently becoming relays.

2. 2 Step 2

   Do

   Filter Mote output for ^-- DAG root$|^-- MOP:. Compare root, actuator and floor-router state.

   You will see

   Mote 1 reports DAG root; root and sampled nodes report Non-storing.

   Why it matters

   The mode determines where downward state lives. It must fit upward telemetry and occasional downward commands, not just node count.

3. 3 Step 3

   Do

   Filter for ^-- fd00::(208|209|20a). Read the root’s route links for the three leaves.

   You will see

   Root state maps leaves 8 and 9 through router 3, and leaf 10 through router 5.

   Why it matters

   DAO-derived root-held links are needed for the Non-storing downward path. A parent diagram alone is insufficient.

4. 4 Step 4

   Do

   Filter for ^fe80::20[23].*=>. Check floor-two router 4’s upstream candidate and compare the README tie worksheet.

   You will see

   Router 4’s candidate 2 advertises Rank 256 with link metric 135, giving candidate Rank 391.

   Why it matters

   Actual Rank follows the objective function and link evidence, not floor height. A worksheet tie needs explicit stability or hysteresis evidence before choosing.

5. 5 Step 5

   Do

   Filter for Received ping reply from fd00::209. Check the root-initiated probe to the floor-two actuator-role mote 9.

   You will see

   Root 1 receives the reply at 140.140 s, len 4, ttl 63, delay 75 ms.

   Why it matters

   This probes a real downward packet and its return, alongside ordinary upward telemetry. It proves an ICMP path, not actuator mechanics or command authorization.

6. 6 Step 6

   Do

   Filter for ^-- Preferred parent|^-- Rank:. Record the final sampled parents and complete the README role, traffic, mode and validation table.

   You will see

   The root Rank is 128; actuator-role mote 9 has parent 3 and Rank 402; floor-two router 4 has parent 2 and Rank 391. The full log has 130 root receptions from all nine clients and replies to all nine.

   Why it matters

   The design can be accepted for these measured mesh paths, with explicit limits for power, memory, external routing, security and future link changes.