IBM 990 - Manual (Page 249)

Appendix A. Hardware Management Console (HMC) 237
Figure A-2 Multi CPC environment
Important: Beginning with the next zSeries server, after the IBM ^ zSeries 890
and 990, all new HMCs on all currently marketed zSeries servers are intended to become
closed platforms. They will only support the HMC application and not the installation of
other applications, such as the IBM ESCON Director and the IBM Sysplex Timer console
applications.
When available, the next generation HMC is expected to communicate only with G5
Servers, and above (Multiprise 3000, G5/G6, z800, z900, z890, z990). TCP/IP is intended
to be the only communications protocol supported.
LAN LAN
zSeries z990
HMC
HMC
zSeries z900 G5/G6 Series