[openbeosnetteam] Re: A possible redesign

> <*snip*>
> type of card. Each module is then given a list of other modules as they
> are loaded, building a chain. The PPPoE module (or Ethernet IP) module
> would say, "Hey! That's an ethernet card! and register some packet type
> with it, or ask to be given all packets, or something along those
> lines. As a packet moves through the stack, it will acquire attributes,
> and its data pointer will be modified so that the contents of the
> packet are simply its payload. The attributes would include information
> like destination and source addresses, packet types, etc.

Is this fast enough? I mean, we would have to copy the attributes or at
least specify where they are and how much space they use (and which type,
like int32+endianness). Alternatively, attribute access could be routed to
each protocol, so that we do not copy attributes. Where is the difference to
the current implementations? We ask the IP protocol for the IP address.
IMHO, this is like asking for an attribute.

> This would allow IP or AppleTalk stacks to be oblivious to the link
> type, as sub-modules (with appropriate types, like "ip/ethernet" (the
> second part of the type could even define on top of which layers it was
> placed)) would translate network-protocol specific header information
> into a standard set of attributes.

Do I understand you correctly that you want to use translator modules for
each protocol combination?
IP is a module that exports some attributes and Ethernet, too. There are no
hard-coded types in both protocols. To connect IP with Ethernet we need a
translator module that knows the attributes of IP and Ethernet.
Additionally, this module combines all attributes into standard attributes
so that they can be used by applications?
Why do we need a standard set of attributes? IPv6 uses other IP addresses
than IPv4. Shouldn't applications be aware of this? I mean, there are many
protocol-specific attributes that are useful to the app-layer. How do you
want to translate the concept of ports? I think I did not understand what
you mean with "standard attributes".

Waldemar

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