The following are best practices from this chapter:
• Create a dial plan in advance. Identify all required normalization rules and user dialing habits.
• Plan the voice policies, PSTN usages, and routes to match the different levels of service required to each user.
• Use existing data to analyze PSTN usage in order to estimate IP/PSTN port requirements.
• Assign a backup registrar to pools where voice resiliency is required.
• Deploy survivable branch servers or survivable branch appliances in branch offices without resilient WAN links.
• Complete the network configuration before attempting to enable Call Admission Control, Media Bypass, or Enhanced 911.
• Apply appropriate bandwidth policy limits to sites where WAN bandwidth ...