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SIP VoIP, or Session Initiation Protocol VoIP, is a type of VoIP that allows you to replace phone lines with VoIP phone lines on a one-to-one basis. SIP trunking can also be used to consolidate voice, text, and video calls.
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How SIP Works
SIP VoIP-enabled systems transmit data and signals over the Internet by creating connections between users and an Internet telephony service provider (ITSP). SIP allows users to tap into the public telephone network without an individual VoIP-enabling gateway.
The most practical application of SIP is SIP trunking; a SIP trunk can replace a traditional phone line to turn a traditional, conventional phone system into a VoIP phone system.
SIP trunking is a cost-effective way to simplify telecommunications infrastructure, as it works on one IP-based network instead of redundant telephone and data networks.
A regular phone number on your phone system, also known as a Public Switched Telephone Network (PSTN) number, is replaced with an IP address. SIP VoIP can search for a username on an IP network and use that to connect the right phone number with the right IP address and extension.
SIP-enabled phones that call each other simply connect by using the other system's IP address. But for SIP VoIP systems that call PSTN phone numbers, SIP turns its IP address into a PSTN number that is similar to the number being called. If a phone call is not answered or busy, SIP VoIP forwards the caller to voicemail or a call waiting tone.
SIP VoIP functions within the Internet domain, in addition to gateways that can connect a SIP VoIP telephone to a PSTN in most countries.
Benefits of SIP VoIP
The reason many individuals and businesses use SIP VoIP is due to the cost savings with VoIP and increased network capacity.
SIP VoIP providers offer services that reduce costs and improve employee productivity. That's because SIP VoIP is easy to configure. As a result, communications infrastructure is less expensive to design, maintain, and upgrade.
There are many benefits to consider with SIP VoIP.
Benefits of SIP trunking:
- Low-rate long-distance and international calls
- Elimination of IP-PSTN gateways or entire PBX systems: SIP trunking directly connect to the Internet without going through the PSTN, so IP-PSTN gateways aren't needed
- Elimination of a redundant network: SIP trunking only requires a single IP-based network
- Eliminate BRI and PRI (Primary and Basic Rate Interface, respectively) subscription fees: SIP trunking involves a direct connection to the ITSP, so BRIs and PRIs can be replaced (this saves a lot of money).
Features of SIP VoIP
SIP VoIP communications work on multiple SIP-enabled devices:
- Phones, gateways, proxies, and servers
- Softphones (software applications on PCs and mobile devices)
- PBX (Private Branch Exchange) systems
- Instant messaging (IM) programs
- Videoconferencing systems
- Collaboration systems
SIP VoIP providers offer an array of features:
- Caller ID
- Call or media transfer
- Call conference
- Call hold
- Call recording
- Call routing
- Do Not Disturb
- Remote extensions
- Push to talk intercom
- E911 capability
- Auto attendant
Other SIP Services
Some SIP VoIP providers also offer gateway services, which connect phone calls to PSTN phone lines. These calls are usually less expensive because the service uses cheaper local call rates.
In addition to managing telephone calls, SIP services offer customizable applications for many types of communications media. For example, SIP services include multi-player games, video conferencing, and chatting.