Linux kernel design patterns - part 3 [LWN.net]

Linux kernel design patterns - part 3

Posted Jun 23, 2009 10:39 UTC (Tue) by marcH (subscriber, #57642)
In reply to: Linux kernel design patterns - part 3 by johill
Parent article: Linux kernel design patterns - part 3

> I haven't even figured out whether you were trying a rebuttal or not, nor what the TCP/IP specification has to do with the original thesis.

Well, since I am not sure either what you are trying to say, I guess we are even ;-)

So let me rephrase and summarize my point: TCP/IP is incredibly successful. Does this prove or invalidate the midlayer anti-pattern?

I think TCP/IP´s success proves that the midlayer is an anti-pattern, because:
- TCP is not a midlayer but an (optional) library;
- IP has been shrunk to the smallest possible network midlayer 3. Unlike for other subsystems, it is unfortunately practically impossible to shrink a network midlayer 3 down to zero. You need a mimimum set of conventions, and IP is good at reaching this minimum.
- the BSD socket API sucks but it is not really relevant to this question.

What I am NOT saying: IP is the best network layer 3. There are other aspects than this midlayer question.

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Linux kernel design patterns - part 3

Posted Jun 23, 2009 10:59 UTC (Tue) by johill (subscriber, #25196) [Link]

Right, so I guess we're just talking about different things. I think IP or TCP as implemented in Linux disprove the "midlayer mistake" antipattern, while you're saying that to the network, TCP or IP are more libraries than layers. I don't think there's any agreement or disagreement, unless I'm misunderstanding you (again) you're talking about the network, while I'm talking about the implementation.

Linux kernel design patterns - part 3

Posted Jun 23, 2009 12:09 UTC (Tue) by marcH (subscriber, #57642) [Link]

I was not thinking about any Linux-specifics at all. That probably explains our misunderstanding to a large extend.