Could you tell whether it is a BSS failure during HO preparation or a BSS failure during a HO execution ? What’s the reference name of the indicator you’re looking at ?
I doubt there is any kind of uncompatibility between alcatel bss and siemens nss, so the solution certainly lies in your NSS and OMCR settings.
I can’t point exactly what you should check, but you could check out those:
– external LAC / CI are defined in neighbor OMCR
– CI & LAC definition in MSC, routing tables, etc. (i don’t know nss..)