Hi Sheik,
Your only option for Spectrum 10.1.2 would be a custom integration. Nothing out of the box, nor supported by CA.
Prior to Spectrum 10.2, we only supported the integration with CA Service Desk. The enhancements that went into Spectrum 10.2 now allows for integrating Spectrum with BMC Remedy ITSM, ServiceAide, HP ServiceManager, and ServiceNow, in addition to CA ServiceDesk. For more information on the additional integrations see the "CA Spectrum and Service Desk Integration" documentation (https://docops.ca.com/ca-spectrum/10-2-2/en/integrating/ca-spectrum-and-service-desk-integrations)
As for the ServiceNow Istanbul integration, this will require Spectrum 10.2.x. Spectrum 10.2.0 only supports the ServiceNow Geneva and Helsinki releases. For more information on integration compatibility see the Spectrum 10.2.2 Release Information documentation (https://docops.ca.com/ca-spectrum/10-2-2/en/release-information/integration-compatibility).
Regards,
Brad