Finance/Banking network engineers have you guys ever been through mergers/acquisitions?

Hey guys,

As the title says have any of you guys ever been though mergers/acquisitions from a networking point of view?

I dealt with the banking industry before but I have never had to merge multiple bank networks into one bank before, is their anything I should be aware of during this process, i`m aware of asset management, PCI compliance stuff, overlapping addressing, (not sure what routing looks like as yet or switching)

Any tips from your environments on a good recommended latency for finance/banking applications such as fiserv, Temenos?

Any tips on what would be a best practise approach overall would be appreciated.