Changes between Version 1 and Version 2 of Old/NodeHandler/Broadcast
- Timestamp:
- Apr 10, 2006, 8:14:04 PM (19 years ago)
Legend:
- Unmodified
- Added
- Removed
- Modified
-
Old/NodeHandler/Broadcast
v1 v2 7 7 8 8 == Introduction == 9 The current NodeHandler code works satisfactorily on the small grid and the sandboxes. But this same code fails to work correctly on the big grid. This is due to the fact that in the current grid consisting of 400 nodes, packet loss is a major problem. And this problem escalates sharply with the increase in the no. of nodes. Specifically, when trying to image more than 150 nodes in a single attempt, the high packet loss prevents successful completion. To alleviate this problem, it has been decided to explore the use of broadcast instead of multicast. 9 The current NodeHandler code works satisfactorily on the small grid and the sandboxes. But this 10 same code fails to work correctly on the big grid. This is due to the fact that in the current 11 grid consisting of 400 nodes, packet loss is a major problem. And this problem escalates 12 sharply with the increase in the no. of nodes. Specifically, when trying to image more than 150 13 nodes in a single attempt, the high packet loss prevents successful completion. To alleviate 14 this problem, it has been decided to explore the use of broadcast instead of multicast. 10 15 11 16 == Major Design Requirements == 12 17 '''R.1:''' 13 18 {{{ 14 It has been decided that all communications from the NodeHandler to the NodAgent will be through broadcast and that all feedbacks from the NodeAgent to the NodeHandler will be sent through TCP. This is because then 19 It has been decided that all communications from the NodeHandler to the NodAgent will be 20 through broadcast and that all feedbacks from the NodeAgent to the NodeHandler will be sent 21 through TCP. This is because then 15 22 16 23 - reliable feedbacks can then be ensured, … … 26 33 {{{ 27 34 All communication will be handled in the communication layer which will be a separate process. 28 The present focus is on exploring reliable communication with minimum packet loss and once this issue is resolved, the issues pertaining to converting this process into a loadable library will be addressed to. 35 The present focus is on exploring reliable communication with minimum packet loss and once this 36 issue is resolved, the issues pertaining to converting this process into a loadable library 37 will be addressed to. 29 38 30 39 This will need changes to the communication layer in both the NodeHandler and the NodeAgent. … … 35 44 The communication layer will use two separate approaches, one for sending messages and the 36 45 other for receiving messages. Messages being sent from the NodeHandler to the NodeAgent will 37 use broadcast. A single message will be broadcast by the NodeHandler and this message 38 will bereceived by all the NodeAgents.46 use broadcast. A single message will be broadcast by the NodeHandler and this message will be 47 received by all the NodeAgents. 39 48 40 49 Messages being received from the NodeAgent will be use TCP. The NodeAgent communication layer … … 45 54 {{{ 46 55 The messages sent from the NodeHandler to the NodeAgent consist of commands to be executed on 47 the NodeAgent. Since the communication layer will broadcast the message to all the nodes, the NodeAgents will have the filters to deteremine whether a message is to be accepted / rejected. Current NodeAgent code has such filters and these will be enhanced only if necessary. 56 the NodeAgent. Since the communication layer will broadcast the message to all the nodes, the 57 NodeAgents will have the filters to deteremine whether a message is to be accepted / rejected. 58 Current NodeAgent code has such filters and these will be enhanced only if necessary. 48 59 49 60 After a message is sent, the communication server will wait for ACKs from the NodeAgent, which