**What is Voice over Long-Term Evolution (VoLTE)?** VoLTE is *an LTE high-speed wireless communication standard for voice calls and SMS using mobile phones and data terminals.* > **What is the voice and data capacity of VoLTE when compared to 3G UMTS?** > When compared to 3G UMTS, VoLTE has *three times more voice and data capacity.* > > **What is the voice and data capacity of VoLTE when compared to 2G GSM?** > When compared to 2G GSM, VoLTE has *six times more voice and data capacity.* **Why does VoLTE use less bandwidth?** VoLTE uses less bandwidth *because VoLTE packet headers are smaller than those of unoptimized VoIP/LTE.* **Who and what needs to have VoLTE implemented in order to make a VoLTE call?** In order to make a VoLTE call, VoLTE needs to be implemented by: * Both devices. * Both devices' firmware. * The mobile telephone providers on each end. * The inter-carrier connectivity. **What has VoLTE been marketed as by some carriers?** VoLTE has been marketed by some carriers as *HD voice.* # Overview ...