VoIP Vs IP Telephony
VoIP Glossary

Technically there is a difference between VoIP and IP Telephony terms. Following is my brief explanation and example. 

• IP Telephony is when you make on-site call within your LAN (local area network) at home or work. For instance, when calling to a co-coworkers or manager.

• VoIP (short for Voice Over Internet Protocol) is when you make a call to an off-site location or WAN (Wide Are Network). For instance, when you call to your family, friend, co-worker at branch office in different city or across the ocean.

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