Most organizations with IP Telephony in mind use a legacy-based PABX with associated voice mail components - and it's just not possible to switch to a single voice, video and data network overnight. A well-planned migration strategy is critical. That's where you can rely on Cisco to help.

	Network Design Guide [website]
Learn more about network migration and get best design practices in the Network Design Guide.

For information on how to get Cisco Certified, see the Cisco IP Certification page .