Re: [gentoo-user] Re: [WAY OT] wanna learn networking internals

[Alan McKinnon]

On 03/09/2015 03:16, James wrote:
> Alan McKinnon <alan.mckinnon <at> gmail.com> writes:
>
>
>>> Last, I suggest a parallel learning of C/C++ as it really helps
>
>> ^this^, after the basics are fully mastered.
>
>> netmasks make no sense at all until bitwise operators are fully
>> understood. Even CIDR notation is not really obvious until you
>> understand what languages like C do with the 32 bit words we call IP
>> addresses. All x10 when IPv6 comes into play
>
>
> Huh. I find teaching networking, including the intricacies  of advanced
> protocol design, implementation and debugging, are far simpler if
> folks know at least one programming language. Bit manipulations
> are but one part of logic, sequential circuits timing and such
> of the Computer Engineer's domain.  In my experience, if folks read too
> much, but do not play with some codes  on actual hardware, it all becomes a
> giant nebula. I guess I just like the practical side of these issues, to get
> folks hooked on hardware.

Yes, knowing at least one language is key

>
>
> How a serial port (rs_232) works and the putting ppp over that is very
> keen for teaching networking. ymmv. You can also use a protocol analyzer to
> see some cool things. Many codes are published and looking at how a
> microprocessor handles basic packets is very stimulating and encouraging.
> Too bad most kids now days do not get to work on embedded hardware and build
> up an executive or state machine and send/recieve data over interfaces.
> Granted I worked in the world where assembler was
> king (embedded) and assembler folks learning C and tcp/ip were easily amazed
> and happy to migrate from assembler to C.

I think the critical thing is to have a good grasp of what the
technology you use is built on.

C is a thin wrapper around assembly so to master C you should know cpu
instructions, logic and at lest something about hardware. I don't
believe it's possible or desirable to completely abstract something like
C away from those things and still use it well. It's C, not the ISO 7
layer model

>
> As Joost pointed out, I guess it really depends on the background of
> the student. Being a hardware guy, I guess my focus is tainted....

I'm a hardware and electronics guy too. I spent hours in college
building circuits with breadboards, 74xx TTL chips and bits of wire
before they'd let me move onto the next thing

>
> So, fair enough, but how long (exactly what are the basics) do you
> read before you go to the lab and play? Labs are always more fun
> than classrooms, lectures and stuffy old farts.............(gotcha!) ?

The raspberry pi was specifically built to get back to those old days,
the main designers were from the BBC micro era.

Which I think is a wonderful idea.

>
>
> cheers,
> James
>
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-- 
Alan McKinnon
alan.mckinnon@×××××.com