An IP phone is a telephone set connected to IP network that enables users to make VoIP calls. With an IP phone, users can make calls utilizing their internet access while continue to surf the Net or read emails. The main benefit of using IP phones is communication cost saving especially for those making a lot of long-distance or international calls. In fact, calling among IP phones is usually free of charge.

Tha drawbacks are the voice quality may be somewhat inferior to the normal telephony service and if there is a power outage, the IP phone will not work. Another issue is IP phones normally don't have their own phone numbers for people to make calls to. However, more and more service providers are offering the inbound phone numbers.

Most IP phoes these days are based on SIP. So they may sometime be called SIP phones.

Alternatives to IP phones are soft phones or web phones and analog terminal adapters ATA that enable users to make call from their PCs and from analog phone sets respectively.

Check out the links provided here for more information about IP phones.

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