Connection of an SE server to a customer network
SE servers can be connected to a customer network either directly or via the Net Unit (internal LAN switch of an SE server).
As is to be expected, the direct connection provides somewhat higher performance because the transaction time is somewhat lower than via the Net Unit.
LAN connection to a /390 server
A /390 server is always connected to a LAN via an HNC (High-speed Net Connect) channel adapter (see the "HNC" manual [13 (Related publications)]).
An HNC is equipped with the following controllers:
A Fibre Channel Controller for direct connection to the /390 server
A Gigabit Ethernet Controller for connection to the customer network
It is possible to operate more than one HNC on a /390 server. Up to two GFC channels are supported between an HNC and a /390 server.
LAN connection to an x86 server
X86 servers are connected to a LAN via a PCIe controller. The I/Os to the controller are - like all I/Os - directed via the I/O processors.