Current networks mainly make packets transmission decisions by congestion control and packet routing. By doing so, it can achieve high scalability and good fault tolerance. However, this kind of method cannot achieve low latency. Basically, the high latency is because of the queue, which is used for absorbing packet bursts. The mean delay maybe low, but the tail delay is high.
The authors try to design a centralized arbiter to control all packets's timing and routing path. They try to build a system that can allow endpoints burst at the full-bandwidth capacity, at the mean time, eliminating congestions at switches.
There are three main components:
1 time slot allocation algorithm. It is used for determine when should each packet being sent at endpoints.
2 path assignment algorithm. It enable the arbiter to decide which routing path should a packet being sent.
3 a replication strategy for the central arbiter. It is used for failure recovery.
Previous works also focus on using centralized controller, in order to get better load balancing and network sharing. However, they work at the control plane for the coarse granularity. Therefore, it cannot provide packet-level latency control and allocation over small time scale.
For the trade-off, the centralized arbiter is not good for the scalability of data center networks. Since it only contain one arbiter, when the system scales, the arbiter may be the bottleneck.
I think this paper could not be influential in 10 years. Since it is not suitable for scalability.
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