IBM communication controllers have reliably carried the bulk of the world's business traffic for more than 30 years. Over the years, IBM controllers have been enhanced to the point that the functional capabilities of the current products, the 3745 Communication Controller and the 3746 Nways Multiprotocol Controller , surpass the capabilities of any other data networking equipment ever developed. Beyond the SNA architecture PU Type 4, beyond APPN, even beyond IP routing, these controllers support an extraordinary set of functions and protocols. Because of their long history and their functional richness, IBM controllers continue to play a critical role in the networks of most of the largest companies in the world.

Over the past decade, however, focus has shifted from SNA networks and applications to TCP/IP and Internet technologies. In some cases, SNA application traffic now runs over IP-based networks using technologies such as TN3270 and Data Link Switching (DLSw). In other cases, applications have been changed, or business processes reengineered, using TCP/IP rather than SNA. Consequently, for some organizations, the network traffic that traverses IBM communication controllers has declined to the point where it is in the organization’s best interest to find functional alternatives for the remaining uses of their controllers so they can consolidate and possibly eliminate controllers from their environments.

This IBM Redbooks publication provides you with a starting point to help in your efforts to optimize your communication controller environment, whether simply consolidating them or migrating from them altogether. We discuss alternative means to provide the communication controller functions that you use or ways to eliminate the need for those functions outright. Where multiple options exist, we discuss the relative advantages and disadvantages of each.

Part 1. Getting started

Chapter 1. What to do

Chapter 2. Controller optimization examples

Chapter 3. Hot topics - SNI, EP, BSC, and X.25

Part 2. Functional alternatives reference

Chapter 4. Communication controller hardware

Chapter 5. Network Control Program (NCP)

Chapter 6. X.25 NCP Packet Switching Interface (NPSI)

Chapter 7. MERVA Extended Connectivity

Chapter 8. X.25 SNA Interconnection (XI) and Network Supervisory Function (NSF)

Chapter 9. Emulation Program (EP)

Chapter 10. Network Terminal Option (NTO)

Chapter 11. Network Routing Facility (NRF)

Chapter 12. Non-SNA Interconnection (NSI)

Chapter 13. Teleprocessing Network Simulator (TPNS)

Part 3. Strategic solution technologies

Chapter 14. Net390 architecture

Chapter 15. OSA-Express

Chapter 16. Communication Controller for Linux on System z9 and zSeries (CCL)

Chapter 17. TCP/IP

Chapter 18. TN3270

Chapter 19. Enterprise Extender (EE)

Chapter 20. Message queuing (MQ)

Appendix A. Physical inventory worksheets

Appendix B. Logical and functional inventory worksheets

Appendix C. Avoiding VTAM network addressing problems