Transcript Slide 1
This paper is Misleading Shu, Johnny Paper summary Many IP assumptions are wrong IP is not suitable for some networks Suggest using circuit switching as “core” of the network Some bricks IP network is designed to support multiple services Current circuit switching networks are mostly service-specific IP dominates communications Unfair comparison – – – Telephone and TV networks around much longer Circuit switching been sole media Growth tendency Revenue comparison not meaningful – – Makes more sense to compare transactions or data size IP has much better cost effectiveness IP is efficient Claim: multiplexing not significant as utilization is kept low due to burstiness – – – Bandwidth is never enough Circuit switching also benefit from statistics Bad service is better than no service IP is efficient (cont.) Claim: people are willing to pay more to keep utilization low – – Should be a tradeoff left to user Depending on application, predictability may not matter IP is efficient (cont.) Claim: similar response time – – – Wrong definition: should be start seeing something Circuit switching has higher overhead When overloaded, maybe slow, but with progress IP is robust Without the base of the same functionality, the comparison of the reliability is meaningless The authors also believe that the edge network will be packet switching dominated – Should compare the robustness of the CORE network IP is robust (cont.) Government-mandated high availability of the telephone network does not mean circuit switching will inherently has high availability Routing in IP network is much more complex than the routing in telephone network, which is a purely prefix decided scheme IP is simpler The complexity is not inherited from packet switching. – Complexity is from VPNs, IPv6, QoS, Security, access control, etc. If we want the circuit switching to be a general purpose network, will it still be as simple as today? IP support QoS The difficulty of the QoS support in the traditional IP network is not the technical difficulty, instead, it’s because of the backward compatibility Conclusion Most of the comparison between the packet switching and circuit switching are misleading, since the current functionalities of them are totally different Technically, is it difficult to simulate the circuit switching based on the packet switching?