@@ -65,8 +65,11 @@ We seek to demonstrate that these re-convergence times would cause operational f
**Avoiding Switching Bottlenecks with Multipath Routing**
- In a careful literature review and analysis, we will show that Layer-2 Solutions (switched ethernet) necessarily cause switching bottlenecks that create Single Points of Failure and increases in Message Delivery Times to NCS.
**@Nick**
- can you review that worst-case-packet-delay-time paper and see if we can add more beef to this argument, including some charts & graphs & references?
From [worst-case-packet-delay-time paper], we know that the worst case communication delay over Ethernet occurs when the number of frames attempting to communicate over a single switch is the greatest. For example, when a spanning tree organizes itself such that 24 stations are connected to a single switching hub, a typical 144-bit message with a bit time of 0.1 us would take more than 1.5 ms to finish sending a single packet from all stations. If the packets could be interconnected without the tree structure required by Ethernet/IP, transmission time could be brought down to just over 300 us.
The above figure compares strategies for reducing communication time. The parameter which has the largest parameter is the number of frames being communicated over a single switch. This is to be expected, since that parameter will have a multiplicative effect on the queuing delay. By sacrificing the spanning tree topology and leveraging multipath routing without the added processing delays and stateful nature of ECMP or other link-state routing methodologies, we will drastically reduce frame count and, therefore, communication time.
