This is a simple demonstration on how DVMRP operates on the Ohio Computer and Communication ATM Research Network (OCARNet). In the demo, node 0 is the sender (which keeps sending data packets) and node 15, 23, 24, 25, and 26 are the receivers in a multicast group. On-tree nodes and links are labeled in red. As the demo shows, a multicast tree is contructed and torn down by (repeatedly) going through the flooding phase, the pruning phase, and the flushing phase. (Note how a router that is not a group member initially receives data packets in the flooding phase and gets pruned when a prune message is set upstream in the pruning phase.)
This is a simple demonstration on how CBT operates on the OCARNet. In the demo, the core is node 14 (Columbus) and nodes 2, 7, 10, 20, 23, 24 are group members in a multicast group. On-tree nodes and links are labeled in red. A link turns aqua to indicate a join-request or a quit-notification message is being forwarded on it.
In this demo, we compare four scheduling algorithms: VirtualClock (VC), WF2Q+ (an approximation of WF2Q), Self Clock Fair Queueing (SCFQ) and Start Time Fair Queueing (STFQ). The parking lot scenario is used as the network topology (see below). Four connections are established with parameters shown in the following table. In particular, packets of the four connections all traverse, and compete for the link bandwidth, on link 2 at node 4. The clips show the message schedule under the different scheduling algorithms on link 2 at node 4. Also provided are the average queueing delay and the average backlog. (The average queueing delay is obtained as follows. When a packet is transmitted, the average queueing delay is updated using the formula d = d * 0.9 + new_d * 0.1, where d is the running average and new_d is the queueing delay the packet just experienced. The average backlog is the time average of backlog in each connection queue.)
| Connection | Path | Rate | Burst |
| 1 | 0-2-3-4-7 | 50 | 1000 |
| 2 | 1-2-3-4-7 | 50 | 1000 |
| 3 | 5-3-4-7 | 50 | 2000 |
| 4 | 6-4-7 | 90 | 2000 |
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