| 31 | | The main component of the Experiment Management Service is the '''Node Handler''' that functions as an Experiment Controller. It multicasts commands to the nodes at the appropriate time and keeps track of their execution. The '''Node Agent''' software component resides on each node and listens to commands from the '''Node Handler''' and reports information back to the '''Node Handler'''. The combination of these two components controls the testbed and enables the automated collection of experimental results. Because the '''Node Handler''' uses a rule-based approach to monitoring and controlling experiments, occasional feedback from experimenters may be required to fine tune its operation. |
| 32 | | The disk-loading '''Frisbee''' server is designed to quickly load hard disk images onto the nodes using a scalable multicast protocol. It allows different groups of nodes to run different OS images. |
| | 31 | The main component of the Experiment Management Service is the '''Node Handler''' that functions as an Experiment Controller. It multicasts commands to the nodes at the appropriate time and keeps track of their execution. The '''Node Agent''' software component resides on each node, where it listens and executes the commands from the '''Node Handler'''. It also reports information back to the '''Node Handler'''. The combination of these two components gives the user the controls over the testbed, and enables the automated collection of experimental results. Because the '''Node Handler''' uses a rule-based approach to monitoring and controlling experiments, occasional feedback from experimenters may be required to fine tune its operation. Figure 4 illustrates the execution of an experiment from the user's point-of-view. |
| | 32 | |
| | 33 | Finally, using the '''Node Handler''' (via a dedicated experiment called ''imageNodes'', see here), the user can quickly load hard disk images onto the nodes of his/her experiment. This ''imaging process'' allows different groups of nodes to run different OS images. It relies on a scalable multicast protocol and the operation of a disk-loading ''Frisbee'' server from M. Hibler et al. ([http://www.cs.utah.edu/flux/papers/frisbee-usenix03-base.html link]). |
| | 34 | |
| | 35 | [[Image(OMF-User-View.png)]] |
| | 36 | [[BR]]Figure 1. Execution of an Experiment from a User's point-of-view |
