I can say that I mostly agree with the authors. By carefully identifying what the end points are and what they need, we can design a system that will suit its needs. The paper comes to me as a guideline; even though it promotes the use of placing function (reliability, for example) at higher levels [2], it also states that this is not true for all cases. So in order to have a protocol suite that will be flexible enough to accommodate most applications, each layer must be not clearly defined. This will make it easier to add protocols that will meet the needs of an application’s end points. [1] A good example that this principle works is the Internet Protocol Suite [4].
End to End arguments are all about making acceptable sacrifices, i.e. dropped packets can be safely ignored if it rarely occurs. In the old days it is necessary because systems are constrained by limited resources or computing power; but in the future, it may not be the same. For example: with enough resources at each level or layers of a particular system, it may be possible to have reliability at each level by achieving negligible error rates at all levels. I have not seen an example of this kind of system; and an enhancement to the end to end argument principle regarding reliability that I could think of is the ability to detect early where faults have happened like what the IPMI specification aims to do [3].
References:
[1] J.H. Saltzer, D.P. Reed and D.D. Clark. “End-to-End Arguments in System Design.” ACM Transactions on Computer Systems, Vol. 2, No. 4, pp. 277-288, November 1984Marjory S. Blumenthal and David D. Clark, “Rethinking the design of the Internet: The end to end arguments vs. the brave new world”
[2] Blumenthal, M., Clark, D.D., “Rethinking the design of the Internet: The end-to-end arguments vs. the brave new world”, ACM Transactions on Internet Technology, Vol. 1, No. 1, August 2001, pp 70-109.
[3] http://en.wikipedia.org/wiki/Intelligent_Platform_Management_Interface
[4] http://en.wikipedia.org/wiki/End-to-end_principle
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