Cisco’s new “Quad” Colaboration suite:
http://www.cisco.com/go/quad

CTIOS Troubleshooting
https://www.cisco.com/en/US/docs/voice_ip_comm/cust_contact/contact_center/ctios/ctios7_0/troubleshooting/guide/cti70tsg.pdf

Cisco IOS SIP Guide
https://www.cisco.com/en/US/docs/ios/voice/sip/configuration/guide/15_0/sip_15_0_book.pdf