Network nodes must support a common protocol in order to exchange packets. Transport protocols establish point-to-point connections so that nodes can send messages to each other and have the packets arrive intact and in the correct order. The transport protocol also specifies how nodes are identified with unique network addresses and how packets are routed to the intended receiver.
Open Enterprise Server 2015 or later includes the standard Linux TCP/IP support on SUSE Linux Enterprise Server 11 SP4.
Internetwork Packet Exchange (IPX) was the foundational protocol for NetWare from the 1980s until the release of NetWare 5.0, when support for pure TCP/IP became standard.
To aid with migrations from NetWare to OES, coexistence between IPX and TCP/IP networks is still supported on NetWare, but IPX is not supported on Linux.