C# local TCP/IP stack access

I have a Visual C++ programm with a proprietary point-to-point protocol 开发者_JS百科built on top of TCP/IP sockets that allows a set of messages to be flow between a third party software.

There is a note in documentation to that protocol:

IP logical packets do not necessarily map directly to physical packets on the underlying network socket, they may be broken apart or aggregated by the TCP/IP stack.

What does this mean?

I've write my C# application to connect and due to technical restriction it is able to run and communicate only locally. Plus every millisecond is critical.

Seems this is not about named pipes: pipelist.exe doesn't show any specific entries.

If you are just using loopback there may be no IP packets at all, and in any case (a) the implementor of your protocol should have already taken all that into account and (b) TCP hides all that from you too - it just provides a byte stream interface.

When TCP/IP packets go out over, say, Ethernet, the packets are repackaged as Ethernet frames. This may include breaking up the original packets.

When the frames arrive at their destination, the Ethernet header information is removed and the original packet (reassembled if necessary) is presented to the TCP/IP layer on the destination machine.

But this repackaging can also happen within the TCP/IP stack. TCP and IP are actually separate protocols; IP is responsible for routing, TCP does the "handshaking" (maintains session state, guarantees delivery [or tries to], etc.)

Named pipes are a completely different interprocess communication mechanism. Usually faster than TCP/IP, but typically restricted to use on a single machine, I believe.

IP logical packets do not necessarily map directly to physical packets on the underlying network socket, they may be broken apart or aggregated by the TCP/IP stack.

TCP/IP is not the lowest level network protocol that exists. There are others: the Ethernet protocol that connects ethernet devices, the 802.11x wireless protocols, and others. All this statement says is that a single IP packet may correspond to multiple packets in the lower-level protocols, and that the IP networking layer is responsible for buffering or joining these packets.

Your application shouldn't need to worry about this at all. TCP/IP networking is handled very efficiently by all modern OS kernels, and unless your requirements are very unusual you should never have to worry about the way your application protocol is broken up into packets by TCP/IP or the lower-level protocols.