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[[meta title="Hurdish TCP/IP Stack"]]

The Hurd presently uses a [[TCP/IP_stack|hurd/translator/pfinet]] based on code from an old Linux version.
This works, but lacks some rather important features (like PPP/PPPoE), and the
design is not hurdish at all.

A true hurdish network stack will use a set of stack of [[hurd/translator]] processes,
each implementing a different protocol layer. This way not only the
implementation gets more modular, but also the network stack can be used way
more flexibly. Rather than just having the standard socket interface, plus some
lower-level hooks for special needs, there are explicit (perhaps
filesystem-based) interfaces at all the individual levels; special application
can just directly access the desired layer. All kinds of packet filtering,
routing, tunneling etc. can be easily achieved by stacking compononts in the
desired constellation.

While the general architecture is pretty much given by the various network
layers, it's up to the student to design and implement the various interfaces
at each layer. This task requires understanding the Hurd philosophy and
translator programming, as well as good knowledge of TCP/IP. 

This is [[GNU_Savannah_task 5469]].

Possible mentors: ?

Exercise: Make some modification to the existing pfinet implementation. (More
specific suggestions welcome... :-) )