VoIP Phone Adapters

With the advancement of technology, many businesses are moving away from traditional telephone systems to VoIP phone systems. These systems come with a number of benefits:

  • The VoIP phones allow for unlimited and less costly global calling. According to Business.com, businesses can enjoy up to $35 a month on average as savings with VoIP.
  • They deliver SRTP-encrypted and HD voice services
  • The phone systems have presence capabilities which can notify you if a team member is free for a call or not.
  • VoIP phone systems have mobile and desktops apps which enables you to work from any device, from anywhere, at any time.
  • To enjoy the VoIP phone services, you need several tools, including softphones, IP conference phones, cordless phones, sidecars, webcams, headsets and analog terminal adapters (ATA).

What Is a VoIP Phone Adapter?

VoIP phone adapters, also referred to as analog terminal adapters, are mainly used to increase the range of the VoIP coverage to anyone with an adaptable phone via the FXS ports. Through the FXO ports, they are also used to maintain one or two phone lines on the analog phone network when the Internet connection is lost.

Compared to purchasing new hardware, VoIP phone adapters are an affordable alternative when considering your options for converting to the VoIP phone service.

How Does It Work with VoIP Software?

To connect the phone to the VoIP services, the phone plugs into an FXS port as an Ethernet cable links the VoIP phone adapter to the Internet through an RJ-11 port. The adapter then switches the analog signals of conventional telephones to the digital signals required for routing over an Internet connection.

The elementary specifications on most models are designed to improve the quality of the voice and sound during calls. With the VoIP adapter, it is easier to concurrently use the Internet while on calls. Also, some models are well-suited with call waiting, call forwarding, voicemail, and other phone features. In addition, there are models that support on-hold music and offer additional security protocols.

Types of VoIP Telephone Adapters

VoIP phone adapters are classified into the following categories:

  • Single FXS: accommodates one phone
  • Dual FXS: accommodates two phones
  • FXS/FXO: accommodates one or two phones. In addition, it can uphold one or two analog lines

To choose an adapter for your organization, consider your current office arrangement and the features that you are looking for in a VoIP phone adapter. For organizations with a large number of phones, they can use VoIP Gateways, which offer more ports than the VoIP phone adapters, to connect their phones to the VoIP services.

Protocols Supported by VoIP Phone Adapters

To decide how the data is distributed over the network, VoIP phone adapters use a protocol which must match with the protocol used by your on-premise VoIP phone or cloud service provider. Most VoIP phones and service support the following protocols:

  • Session Initiation Protocol (SIP)
  • Skinny Client Control Protocol (SCCP)
  • Media Gateway Control Protocol (MGCP)
  • H.323

Examples of the Most Popular VoIP Phone Adapters

If you are considering acquiring a VoIP phone adapter, these are the most popular options for you:

The OBi300 accommodates 1 RJ-11 FXS analog phone port. It either supports an analog voice plan, a fax plan, or an overhead paging plan.

The OBi508vs accommodates 8 RJ-11 FXS analog phone ports, all of which can support a voice, fax, or paging plan.

The MP-112 provides 2 RJ-11 FXS analog phone ports, all of which can support a voice, fax or paging plan.

The MP-114 supports 4 RJ-11 FXS analog phone ports, all of which can support a voice, fax or paging plan.

The MP-118 supports 8 RJ-11 FXS analog phone ports, all of which can support a voice, fax or paging plan.

The MP-124 accommodates 24 RJ-11 FXS analog phone ports, all of which can support a voice, fax or paging plan.


When it comes to VoIP, 8x8 provides a reliable and compliant cloud solution at a demanding level rarely seen by other cloud providers. Don't take your chances with a subpar cloud-based telecom system. Call 1-866-879-8647 or fill out an online form to request a no-obligation quote from an 8x8 product specialist.

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