AXIS 5470e/570/670e User’s Manual Appendix B: SNA Gateways 241Appendix B SNA GatewaysGatewayConfiguration,3174 CU modeSome hints specific to SNA gateways are given below.• AXIS 5470e/570/670e appears to a gateway as a Down StreamPhysical Unit (DSPU), with eight LUs, 1 to 8 (LU 1 may not beavailable).• Only gateways that communicate with DSPUs using SNA overLLC type 2 are supported.• There are basically two types of gateways that the AXIS5470e/570/670e can be attached to: pass-through gateways andconcentrator gateways, as described below.Pass-through gateway Devices attached downstream to this type of gateway are completelyvisible to the host. In other words, each DSPU will have a PUdefinition on the host. Examples of pass-through gateways are IBM3745 Communications Controller, IBM 3174 EstablishmentController, IBM 3172 LAN Interconnect Controller, etc.You need to set up at least one PU and LU definition for each AXIS5470e/570/670e on the host, as described in the VTAM section.When attaching an AXIS 5470e/570/670e to a remote pass-throughgateway, you need to set the mapping of SDLC or sub-channel addressto MAC address in the gateway.Concentratorgateway, generalA concentrator gateway typically behaves as a PU (or a few PUs) to thehost, even though a number of PUs may be available downstream. If itis an SDLC or channel attached gateway, typically only one SDLC orsub-channel address will be used. Examples of concentrator gatewaysare: IBM Communications Manager/2 (OS/2), Novell NetWare forSAA (NetWare 3.x), Microsoft SNA Server (Windows NT), etc.When an AXIS 5470e/570/670e is attached to this type of gateway,you can map the chosen AXIS 5470e/570/670e LU to any host LUyou like. This way, several print servers may be accessed through thesame gateway.
