IP-telephony is not really a new concept and is now available on the market for many years, it’s no more in testing mode. People don’t know exactly what a IP-telephony device is. What is it, how does it work?
Here you will find some information aboujt IP-telephony devices.

A IP-telephony device can be classified in three general categories:

• end stations (such as phones),
  
• gateways and routers,
  
• and controllers.

Like everything else in IT, every category has a specific function that it performs. And if you combine all the functions you will get a complete IP-telephony system.

Hardware and software VoIP phones
There are two types of VoIP phones: hardware and software.

• A hardware phone is a physical device, very similar to your common phone; it has a handset, dialpad, etc. The only thing that is different from your ordinary phone is that it connects to an Ethernet network rather than a telephone network. IP phones are built with all the necessary hardware (and software) to digitize your voice (i.e., codecs) as well as setup and make calls (i.e., signaling and transport).
  
• Software-only phones, or “soft” phones, use the PC’s capabilities to communicate with other PC’s over the Internet, by using the PC’s sound card, CPU and network card as part of the phone’s hardware, and thus, enable a PC to become an IP phone.
  

IP-telephony Controllers
VoIP controllers, also called IP PBXs, manage the VoIP network. They are actually tools that you can use to configure your IP phone: restrict access, enabling functions and passwords, allowing/not allowing certain options, etc. Plus they are performing all the functions of a traditional PBX. IP PBX controllers are PC-based, running a standard OS (such as Microsoft Windows, Linux or Sun Solaris, but very different) with additional software to control the IP-telephony systems. These IP-telephony systems can provide APIs to extend vendor-provided or user-written features and functionality.

IP-telephony Gateway
A IP-telephony Device is a device that connects the VoIP network to your public telephone network (PSTN). In this way, you can make calls and receive them, from your PTSN, even if you are using an IP-based system, just like your traditional phone. Depending on the type of the gateway, they are equipped with analog/digital interfaces in order to connect to your local telephone company. With so many options available today, gateways are also capable of transcoding (changing the signal from one codec version to another so that the IP-telephony device can communicate with the rest of the network). For example, a gateway uses G.729 codec, while your PTSN network uses a G.711 codec.

IP-telephony Routers
IP-telephony Routers are devices that decide where the IP datagrams should go, between networks, from the source to the destination. IP-telephony Routers are inter-network equipments that help a LAN connect to a WAN; therefore the router’s capability to ensure correctly handled high-priority traffic is very important. Since WAN speeds have generally less bandwidth than a LAN, proper packet queuing and prioritization is in order to ensure good voice quality across the path.

Jim Francisto
IP-telephony
Free Online TV
Reverse Cell Phone

To stay with your trusty TDM based PBX telephone system or toss everything out in favor of a Voip phone system?

Why to reject services which would promise to enhance the productivity?
Substitute it all for a brand new Voice over IP phone system and take all the benefits this new technology offers.

How to proceed?

You can decide whether to have:
- analog,
- digital, or
- IP phones
each desk and if to go with VoIP phone services or TDM to connect with the outside world. Some systems will still permit to mix and match.

Which one to choose?
VoIP?
TDM?
or Both?
Why not?

Most any phone system that handles more than a few phone handsets gives you the option on how to connect phones to the PSTN (Public Switched Telephone Network).

A pure Voip phone system completely operates in the IP world from handset to call termination. The PBX equivalent is the IP PBX. The IP PBX is generally a software running on a Linux system. Handsets are referred to as SIP phones.
SIP (Session Initiation Protocol) is the switching protocol that controls the phone calls over the Internet. Calls between subscribers of the same Voip service provider completely stay on the network and never enter the PSTN (Public Switched Telephone Network). Calls to and from non-subscribers are terminated to the PSTN at the provider’s location.

Usually you can mix and match purely digital and TDM phone systems, purely analog phone systems and purely VoIP phone systems. A Voip system may well have FXS (Foreign Exchange Subscriber or Station) ports to connect to analog handsets, as do traditional PBX phone systems. The phone service connection can be ISDN, T1, analog or SIP Trunking.

Usually modern Voip PBX phone systems offer a broader range of handset and phone service connection options than legacy PBX systems. But before you plan to replace your phone system, you may consult a skilled expert or search for relevant information in one of the many Voip Review Sites you’ll find online.

Jim Francisto
VoIP
Voip Blog
Free Online TV

To keep your conventional Phone System or toss everything out in favor of an IP Telephone System?

Why to reject services which would promise to improve your productivity?
Replace it all for a modern Voip phone solution and take all the benefits this new technology provides.

What to do?

You have these possibilities:
- analog,
- digital, or
- IP phones
on your desk and whether to take Voip or TDM to be linked with the outside world. Some systems will still permit to mix and match.

Which one is the right solution for me?
VoIP?
TDM?
or Both?
Why not?

Most any Phone Systems give you the option on how to connect to the PSTN.

A pure IP Phone System operates completely in the IP world from handset to call termination. The PBX equivalent is the IP PBX. The IP Telephone System is generally a software running on a Linux system. The handsets are referred to as SIP phones.
SIP is the switching protocol that controls the telephone calls on packet based networks. Calls between subscribers of the same Voip service provider completely stay on the network and never enter the PSTN. Calls from and to non-subscribers are terminated to the PSTN at the provider’s location.

Usually you can mix and match purely IP Telephone System, purely analog Phone Systems, purely digital and TDM Phone Systems. An IP Telephone System may well have FXS (Foreign Exchange Subscriber or Station) ports to connect to analog handsets, like traditional PBX telephone systems. The service connection can be T1, analog, ISDN, or SIP Trunking.

Generally modern IP Telephone Systems offer a broader range of handset and telephone service connection options than legacy PBX systems. But before you decide to replace your telephone system, you may consult an expert or look for relevant information in one of the many Voip Review Sites you’ll find on the Internet.

J. T. Francisto

VoIP Or Standard PBX

Should you keep your trusty TDM based phone system or toss everything out in favor of a Internet Telephony system?

Why to miss services which would promise to enhance your productivity?
Substitute it all for a brand new Voip phone system and take all the benefits this new technology offers.

How to proceed?

Decide between these possibilities:
- analog,
- digital, or
- IP phones
on your desk and whether to go with VoIP telephone services or TDM to be linked with the outside. Some systems will even allow you to mix and match.

Which one to take?
VoIP?
TDM?
or Both?
Why not?

Most any telephone systems give you the option on how to connect to the PSTN (Public Switched Telephone Network).

A pure IP-Telephony telephone system operates entirely in the IP world from handset to call termination. The PBX equivalent is the IP PBX. The IP PBX is generally a software running on a Linux system. The handsets are referred to as SIP phones.
SIP (Session Initiation Protocol) is a switching protocol which controls the telephone calls over the Internet. Calls between subscribers to the same Internet Telephony service provider completely stay on the network and never enter the PSTN (Public Switched Telephone Network). Calls to and from non-subscribers are terminated to the PSTN at the provider’s location.

Usually you can mix and match purely digital and TDM phone systems, purely analog phone systems and purely VoIP phone systems. A IP-Telephony system may well have FXS (Foreign Exchange Subscriber or Station) ports to connect to analog handsets, like traditional PBX telephone systems. The telephone service connection may be T1, analog, ISDN, or SIP Trunking.

Normally newer IP PBX telephone systems can offer a broader range of handset and telephone service connection options than traditional PBX systems. But before you decide to replace your telephone system, you may ask a skilled expert or get related information in one of the many Voip Review Sites you’ll find on the Internet.

Jim Francisto
has a master degree in IT and is a technical writer and business consultant
Virtual PBX VoIP
VoIP Provider Review
VoIP News

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