Ka-Tel is responsible for managing the telephone network. Terrestrial phone lines will carry over the internet, and therefore – ideally over fiber optic lines. However, since every terrestrial phone account is SIP? based, then the internet is all that’s needed. In the case of cellular networks, the provider must support current standards, and up to 10 years worth of previous networks. This will likely just be one generation old since once a new network system is in place, new phones will use that network bands.
The network provider is responsible for providing for unified voicemail services. This takes it off the job of the carrier’s responsibility. This is to assure that every single person has just one voicemail box to deal with. If there are multiple carriers, then those carriers will forward any unanswered calls to the unified voicemail system. No matter what dialing *86 from a terrestrial phone, or pressing and holding 1 on a cellular phone will enter the unified voicemail system. The customer can choose to disable voicemail services. This is usually only done when there is a telephony server involved, and most likely done by businesses.
The provider can set certain vertical service codes (like *86) as uniformed across the network. This will mean the same vertical service code for turning off/on Caller ID Block no matter the carrier. This assures that some things stay the same no matter the carrier, and since every carrier (other than Ka-Tel) is an MVNO?, it will make sense to use the same vertical service codes.