If you want to see performance sorted by server, use the ‘server-known’ option; for just phones, the ‘phone’ field.
 
 
voipIpType <'admin-reg server' | 'control processor' | 'gateway' | 'media processor' | 'non-server' | 'outside ip' | 'phone' | 'router' | 'server-inferred' | 'server-known' >
 
 
Examples
voipIpType 'control processor'
voipIpType 'gateway'
voipIpType 'router'