Build an enterprise communication platform using an open-source system (VIOP free network phone, fax)

How to build open source VoIP for Enterprises
Techrepublic.com.com
3/8/2006
URL: http://www.zdnet.com.cn/techupdate/intranet_internet/solution/story/0,3800080997,39516384,00.htm

Use asterisk to build enterprise open source VoIP

Many people want to know whether enterprise-level open-source VOIP solutions can be built and whether they are beneficial. This article provides some positive answers to this question.

Use asterisk to build enterprise open source VoIP
Many people want to know whether enterprise-level open-source VOIP solutions can be built and whether they are beneficial. The answer is that this is not only possible, but also the unique feature of Asterisk is that it is an open-source IP Phone platform. Asterisk is not only an IP Call Signal server (sometimes called ip pbx), but also a traditional TDM/analog PBX, and seamlessly bridges the two environments.

In Figure A, we have an enterprise-class hybrid IP/TDM/telephone simulation solution. Note that there is no "pure" ip address solution, because it is impossible to avoid simulated devices and simulated telephone pots (General old-fashioned telephone service) environments. Sometimes companies have to support a simulated fax or telephone port for some businesses. The only problem is how many phone numbers you use and who are using them.

Figure

In my "open-source VOIP" chart, the solution consists of several key components:

Ip pbx (asterisk server)

Voicemail and fax server

Ethernet to T1 Bridge

Channel Processing Unit

Ethernet switch segment (for a coarse-pipe LAN)

Phone Simulation

Analog Fax

Class 5 Ethernet wiring (black)

T1 wiring (red)

Standard analog telephone cable (green)

Router/firewall Device

IP phone number

Computers that contain software IP Phones

PDA containing software IP Phone

Phone company cloud map

Ip pbx (asterisk server)

Ip pbx (asterisk server)
PBX is a broad term, usually a hub device that controls all calls. Ip pbx is a loose term that generally refers to a type of call signal sending server that establishes and negotiates an IP address to an IP phone or IP address to a simulated pots (regular old-fashioned telephone service) Call. PBX also manages the telephone system. In our specific chart, we have two redundant asterisk servers as ip pbx solutions. In this scenario, the asterisk server hardware can be a normal "white box" 1u server worth $1000 to $2500, or from IBM, dell or HP's brand-name servers worth $1500 to $5000. The benefit of Asterisk software is that it can run on common x86 intel or AMD hardware, saving a lot of cost than its patented PBX system by dozens of times.

Voicemail and fax server
The voicemail and fax server functions can be deployed on a single asterisk server. The advantage of this method is that a common server has a larger storage capacity than the patented voice mail solution. Voice mail can be sent. There are already Internet-based Small phone companies that use asterisk to support product-language mail. Asterisk has the following features:

 

Visual indicator of message waiting

Stutter dialing tone for message waiting

Voice mail to email

Voicemail Group

Web voicemail Interface

Ethernet to T1 Bridge
Ethernet to the T1 bridge, such as redfone fonebridge, can be used to connect multiple servers to the 4t1 device. Even a cheaper 4 T1 PCIe card can be used directly on the asterisk server, but it forces you to entrust these T1 resources to specific servers. Fonebridge allows you to use these T1 resources flexibly on multiple servers and is more robust when one server fails. The T1 interface is connected to a telephone company or can serve channel processing units of many analog devices. The value of fonebridge is USD 2200, which is higher than the cost of a quad T1 PCI, but it is not limited to any specified server. If you want to exceed 4 T1, you can add additional fonebridge devices. Digium production, the parent company of Asterisk, was born with the PCI T1 and E1 adapters supported by asterisk.

Channel Processing Unit
The channel processing unit allows you to divide a T1 line into 24 independent FXS or fxo ports. Therefore, if you purchase 1 fonebridge, it takes up a line T1 to connect to the phone company and uses 3 T1 to connect to the 3 24-port channel processing unit, you will be able to support 72 analog phone or fax devices. Here we provide some channel processing unit solutions and a large amount of resources from our suppliers. The price of a 24-port Signal Processing Unit ranges from USD 700 to USD 1500. Considering the cost of power-over-Ethernet, The FXS analog port for power-on is half the price of the IP Phone port for power-on. If you don't need so many simulated ports and you are not interested in building redundant asterisk servers, you may not consider fonebridge or large channel processing units that require USB devices such as astribank 8.

A fxs port on the channel processing unit allows you to insert a analog phone and FXS will power the phone. The fxo port on the channel processing unit allows an upstream connection to the phone company that provides you with the FXS port as a RJ-11 Jack. The following two connection scenarios are valid.

 

Phone (fxo)-(FXS) Channel Bank (fxo)-(FXS) telco

Phone (fxo)-(FXS) telco

Ethernet switch segment
The example in the figure shows a special Ethernet segment. This may be a physically isolated switch or a separate VLAN on the switch. The internal LAN and VoIP segments are isolated by routers/firewalls. If you do not want your phone and phone system to be attacked or infected, we strongly recommend that you use a firewall.

The tdmoe (Ethernet-based time division multiplexing) LAN segment is responsible for the communication between the PBX-voice mailbox and the PBX-channel processing unit. In the past, TDM communication between these devices used expensive T1 cards, but this has been greatly improved by moving TDM communication to a cheap Ethernet.

Phone Simulation

Phone Simulation
Analog phones are common phones that have been used for nearly a hundred years. They are simple, cheap, and easy to use. They do not have so many IP phone features, but they are part of the lives of many people. The analog phone includes an fxo RJ-11 port that is directly connected to the power supply FXS port on the channel processing unit, or to the wall outlet provided by the telephone company.

Analog Fax
Although server-based fax has brought about a revolution in office fax, simple fax machines are still needed in many cases. The fax machine has an fxo RJ-11 port, just like the analog phone, that is directly connected to the power supply FXS port on the channel processing unit, or to the wall outlet provided by the telephone company.

Category 5 ethernet cable
Category 5, category 5E, or Category 6 cables are used for 10-Base T, 100-Base T, or even Gigabit Ethernet. Category 5 is the most commonly used ethernet cable.

T1 cable (red)
The T1 cable is used to connect the PBX, channel processing unit, and the T1 port between telephone companies. One T1 supports 24 standard telephone channels, which is why a T1 port can be divided into 24 independent FXS, fxo ports, or fxo/FXS port combinations. The T1 connected to the telephone company supports 24 concurrent calls.

Standard analog telephone cable
This is usually a copper pair with both ends being a RJ-11 connector. These cables provide enough power to support a simple analog phone. These cables are used between telephone companies, analog phones, analog faxes, and channel processing units.

Router/firewall Device
The vro connects multiple Ethernet segments. A firewall or at least a simple Router Access Control List (ACL) can be integrated to limit the communication traffic between two Ethernet segments. For security reasons, it is always a good idea to limit the communication traffic to a minimum value.

IP phone number
In fact, IP phones are specialized computers that run VoIP Software for special purposes. The IP Phone price ranges from $70 to $700 for a basic unit of customer software including multi-color LCD. An IP phone can be powered by a standard Ethernet consisting of 802.3af POE (Ethernet power transmission), Cisco's patented Poe for a Cisco IP Phone, or an independent AC adapter. Adding Poe to an Ethernet switch adds an additional $50 per port to the cost of a common Ethernet switch.

Computer of software IP Phone
Software-based IP phones or softphones run on general-purpose computers and feature similar to dedicated IP phones. The price of the phone number ranges from free to $50.

Software IP Phone PDA
PDA-based software phones and PC-based software phones are the same, but they run on small PDAs rather than fully functional Laptops and Desktops.

Phone company cloud map
Phone company cloud indicates any common phone company. Companies can connect to the telephone company through a simple single channel copper cable through a wall-mounted RJ-11 Jack, or they can concentrate 24 channels on a T1 line. This is still the most common method for communication between telephone companies.

New phone companies operate on the Internet and allow you to connect directly to them using a cheaper Internet connection. The unique advantage of Asterisk is that it has its own IAX (Inter asterisk exchange) protocol, which allows you to provide over 180 VoIP sessions on a T1 Internet or frame relay connection, the standard T1 only supports 23 voice channels.