IBM 990 - Manual (Page 253)

Appendix A. Hardware Management Console (HMC) 241
Figure A-5 Ethernet only - one path wiring scenario
Additional connections to the Ethernet LAN
Additional connections to the Ethernet LAN may be made to expand the connectivity beyond
the local Hardware Management Console and Support Element (see Figure A-6).
If connections to previous generations of IBM Enterprise Server systems are desired, they
may be connected using Ethernet-to-token ring bridges.
If connection to the enterprise LAN is desired, it is recommended that an Ethernet bridge or
router be installed to isolate the Hardware Management Console and Support Element from
other systems.
Figure A-6 Ethernet only - one-path wiring scenario with additional connections
zSeries 990
HMC
HMC
SE
SE
Ethernet LAN
Bridge Bridge
Token-Ring LAN Token-Ring LAN
zSeries 900 G5-G6 Series
SE
SE
SE
SE
zSeries 990
SE
SE