This week we are covering two related aspects of network resource allocation:
- flow&congestion control - typically end-to-end, running in sending and receiving systems
- scheduling - typically what happens in switches and routers within the network.
Simple TCP-like flow control can operate with First Come First Serve (FCFS or First in First Out/FIFO) schedulers. More complex flow and congestion control might do better with some sort of fair scheduling possibly with per-flow state in the net. More modern end-to-end protocols like QUIC still operate like TCP with regards flow & congestion control.
Open Loop flow control systems have a call setup, and then run according to their traffic descriptor (subject to policing, maybe at the edge of the net) - but they then depend on more complex schedulers within the network to isolate packet flows and potentially provide minimum packet rate and delay guarantees, according to some fairness constraints, so probably need more per-flow state within the network.
No comments:
Post a Comment