https://www.ibm.com/docs/en/ims/15.4.0?topic=coupling-msc-imsplexes-shared-queues
IMS 15.4 - Communications and connections - MSC and IMSplexes with shared queues
The following topics discuss the coexistence of a Multiple Systems Coupling (MSC) network with an IMSplex with shared queues. MSC and IMSplex coexistence can...
imscommunications
https://www.ibm.com/docs/en/ims/15.5.0?topic=network-managing-sysids-when-msc-imsplexes-coexist
IMS 15.5 - Communications and connections - Managing SYSIDs when MSC and IMSplexes coexist
Local SYSIDs must be unique in an MSC network. Local SYSIDs are not required to be unique within an IMSplex; however, local SYSIDs owned by IMSplex members...