voip

The major components of a VoIP network are very similar in functionality to that of a circuit-switched network. VoIP networks must perform all of the same tasks that the PSTN does, in addition to performing a gateway function to the existing public network. Although using different technology and approach, some of the same component concepts that make up the PSTN also create VoIP networks. There are three major pieces to a VoIP network.

- Media gateways

- Media gateway/signaling controllers

- IP network

Media Gateways
Media gateways are responsible for call origination, call detection, analog-to-digital conversion of voice, and creation of voice packets (CODEC functions). In addition, media gateways have optional features, such as voice (analog and/or digital) compression, echo cancellation, silence suppression, and statistics gathering.

The media gateway forms the interface that the voice content uses so that it can be transported over the IP network. Media gateways are the sources of bearer traffic. Typically, each conversation (call) is a single IP session transported by a Real-time Transport Protocol (RTP) that runs over UDP. Media gateways exist in several forms. For example, media gateways could be a dedicated telecommunication equipment chassis, or even generic PC running VoIP software. Their features and services can include some or all of the following.

Trunking gateways that interface between the telephone network and a VoIP network. Such gateways typically manage a large number of digital circuits.

Residential gateways that provide a traditional analog interface to a VoIP network. Examples of residential gateways include cable modem/cable set-top boxes, xDSL devices, and broadband wireless devices.

Access media gateways that provide a traditional analog or digital PBX interface to a VoIP network. Examples include small-scale (enterprise) VoIP gateways.

Business media gateways that provide a traditional digital PBX interface or an integrated soft PBX interface to a voip network.

Network access servers that can attach a modem to a telephone circuit and provide data access to the Internet.

Discreet IP telephones units.

Media Gateway Controllers
Media gateway controllers house the signaling and control services that coordinate the media gateway functions. Media gateway controllers could be considered similar to that of H.323 gatekeepers. The media gateway controller has the responsibility for some or all of the call signaling coordination, phone number translations, host lookup, resource management, and signaling gateway services to the PSTN (SS7 gateway). The amount of functionality is based on the particular VoIP enabling products used.

In a scalable VoIP network, you can breakup the role of a controller into signaling gateway controller and media gateway controller. For calls that originate and terminate within the domain of the VoIP network, only a media gateway controller might be needed to complete calls. However, a VoIP network is frequently connected to the public network. You could use a signaling gateway controller to directly connect to the SS7 network, while also interfacing to the VoIP network elements. This signaling controller would be dedicated to the message translation and signaling needed to bridge the PSTN to the VoIP network.

The services of these devices are defined by the protocols and software they are running. There are several protocols and implementations that any number of vendors could deploy. Knowing the details of how the devices use their suite of protocols is important to designing the IP backbone that is to service the VoIP elements.

IP Network
You can view the VoIP network as one logical switch. However, this logical switch is a distributed system, rather than that of a single switch entity; the IP backbone provides the connectivity among the distributed elements. Depending on the VoIP protocols used, this system as a whole is sometimes referred to as a softswitch architecture.

The IP infrastructure must ensure smooth delivery of the voice and signaling packets to the voip elements. Due to their dissimilarities, the IP network must treat voice and data traffic differently. If an IP network is to carry both voice and data traffic, it must be able to prioritize the different traffic types.

There are several correlations to the VoIP and circuit-switching components, however there are many differences. One is in the transport of the resulting voice traffic. Circuit-switching telecommunications can be best classified as a TDM network that dedicates channels, reserving bandwidth as it is needed out of the trunk links interconnecting the switches. For example, a videophone conversation reserves a single DS-0 channel, and that end-to-end connection is used only for the single conversation.

IP networks are quite different from the circuit-switch infrastructure in that it is a packet-network, and it is based on the idea of statistical availability. Class of service (CoS) ensures that packets of a specific application are given priority. This prioritization is required for real-time applications like net to phone to ensure that the voice service is unaffected by other traffic flows.

More info on reverse phone lookup and
iptv

Some Resources on different Niches:
softwareclub.tk
solarpowernews.info
insurance-quotes-central.com
bluehost-info.com
work-from-homebliss.com
articlewritingmastery.com
yourprepaidcell.com
publishwebeasy.com
articles.informationjunkie.co.uk
im-blueprints.com
imtoolreviewsite.com
birthdaypartydepot.com
bankruptcyinfostore.com
video-camcorder-guide.com
lcd-plasma-tv-guides.com
wordpressadvice.com
biztoolsreviews.com
newcamcorders4u.com
bristolbusinessseminars.com
foodmanagementandrecipes.com
cellphonesbuy.info
bestenergy4u.com
hotcoinslive.com
reverse-phonebook.net
computersciencestudy.info
yukione.com
pc-2-mobile.com
marketingmasterystrategies.com
hosting.free-product-review.com
spyware.free-product-review.com
yourperfectweddings.com
restaurantjobboard.com
Digital-Keyboards.com
imarketportal.com
inmycocoon.com
webterium.com
freesatreviews.co.uk
texasbestbbqandgrill.com
myfavoritebabystore.com
newsletter-subscriptions.com
partycostumeshop.com
astronomy-today.com
advancedexceltraining.com
smalldigitalcamerascenter.com
iphoneinsurance.org.uk
netmarketzine.com
science-and–technology.com
virtumonde.net
phones-faqs.com
stephencconsulting.com
whataboutmycomputer.com
consumerratedhosting.com
cellphonenumbersreverse.com
besthdtvreview.com
thetelevisionmall.com
topresellrights.com
digital-photography-mag.com
bristolbathbusinesswebsites.com
google-cash-detective-2-bonus-review.com
mytvonpc.info
solar-windenergy.info
londonbusinesswebsites.com
graphicsdesignwebsite.com
mindfrolic.com
logicstudiotraining.com

If you have been disturbed by a hoax caller or would regain lost relationship and enjoy with someone and would like to know who has been calling your spouse, you can do this now.

A reverse phone lookup might sound technologically foreign to a lot us but it is simply process to search and trace a mobile phone numbers and other data of the owner of a phone. Depending on the software or system you use, you can get a different level of search results.

It is very simple to detect the owner of a phone number with such a reverse phone book lookup. There are many online companies who may provide information on the owner of a cell phone number. These reverse phone book lookup often claim to be able to do more than they really can. It’s common to find free a reverse cellular phone lookup offering nothing else than only public phone data. These services don’t provide any information on cellular or unlisted phone numbers and are not useful at all.

With a reverse phone lookup you only need to know the actual number that made the call. If you know the approximate time of the call punch the numbers from that time period, and a can do the work for you. A good reverse cellular phone lookup will find the correct person in seconds.

Free websites do not give you full information. Paid reverse phone lookup have spent much time and money to purchase a huge amount of cell numbers and other information of the person owning these numbers.

You will receive all kinds of data that you might be wondering about: The owner’s name and existing address , criminal records, family members, neighbors and relatives, all phone numbers belonging to the owner, marital status and many other interesting facts

Start running your own searches successfully without any stress and say good bye to private investigators. People do searches almost daily on the internet and tens thousands of people searches daily for phone number on with a reverse phone book lookup to discover prank callers, and find old friends. The scope of searches span a wide array of listed, and also unlisted, mobile phone and land line numbers. The fee for a reverse phone book lookup is not expensive and is giving you limitless search option. A test of such a phone lookup service with my own phone numbers really found the correct information for my cell phone. A reliable reverse phone lookup will easily save you many days of fruitless searches and let you trace any telephone number from your caller id or your phone records.

People do searches almost daily on the internet and tens thousands of people searches daily for phone number on with a reverse phone book lookup to discover prank callers, and find old friends. The scope of searches span a wide array of listed, and also unlisted, mobile phone and land line numbers.

VoIP is here to stay
Just a few short years ago most of us could not have provided the name of a single voip phone service provider. Now, after much technological advancement and with the hard work of Internet developers, there are many voip phone service providers popping up all over the place. voip is the latest technology in telephony that allows people to make and receive phone calls over the Internet, much in the same way that email is sent from one computer to another.

Cheap calls like we have never seen
Voice over IP is revolutionary because it has lowered the cost of long distance and international telephone calls to rates that we have never seen before. The most astonishing example of this is that any two users that have the same voip phone service provider can call each other at absolutely no cost. Now this does not matter if the two people are located in the same country. For example, if a voip user in Italy has signed up with the same voip phone service provider as a family member in Mexico, they will be free to call each other at absolutely no cost without limitation. Suddenly there is no distance!

There are many ways to make phone calls over the Internet
People tap into voip in many different ways. Calls can be made from a telephone that has been connected to a router with an Internet connection>, people can make phone calls over the Internet through a computer that has a software installed or there are even phone cards available that voip phone service provider issue to allow people to use normal phones to access a voice over IP phone line for cheaper calls.

There are many positives with VoIP
One of the reasons that a voip phone service provider enjoy almost guaranteed success is that there are many advantages to voip telephone service and not many negatives. People only have to hear about the great rates that are involved and the simplicity of getting connected to this technology and they are ready to convert their phone service to a voip phone service provider.

Do the research on voip
If you have been hearing talk of voip but are unsure which voip phone service provider to contact for service, try doing a little research on the Internet before committing to anything. The only variety that I have found between the various voip phone service providers are the rates that they charge. Some providers will charge for some services and not for others and so if you are looking for the most economic deal, you will have to shop around a bit and do some comparing of rates.

Jim Francisto
voip
voip news

VOIP networks must perform all of the same tasks that the PSTN does, in addition to performing a gateway function to the existing public network. There are three major pieces to a VOIP network.

• multimedia gateways/signalling controllers
• VoIP network
• mulimedia gateways

Media gateways are responsible for call origination, call detection, analog-to-digital conversion of voice, and creation of voice packets (CODEC functions).

The media gateway forms the interface that the voice content uses so that it can be transported over the IP network.Their features and services can include some or all of the following.

• Network access servers that can attach a modem to a telephone circuit and provide data access to the Internet.
• Discreet IP telephones units.
• Residential gateways that provide a traditional analog interface to a voice over IP network.
• Business media gateways that provide a traditional digital PBX interface or an integrated soft PBX interface to a voice over IP network.
• Trunking gateways that interface between the telephone network and a voice over IP network.
• Access media gateways that provide a traditional analog or digital PBX interface to a voice over IP network.

Network access servers that can attach a modem to a telephone circuit and provide data access to the Internet.

Discreet IP telephones units.

Residential gateways that provide a traditional analog interface to a voice over IP network.

Business media gateways that provide a traditional digital PBX interface or an integrated soft PBX interface to a voice over IP network.

Trunking gateways that interface between the telephone network and a voice over IP network.

Access media gateways that provide a traditional analog or digital PBX interface to a voice over IP network.

Media Gateway Controllers
The media gateway controller has the responsibility for some or all of the call signaling coordination, phone number translations, host lookup, resource management, and signaling gateway services to the PSTN (SS7 gateway). Media gateway controllers could be considered similar to that of H.323 gatekeepers. Media gateway controllers house the signaling and control services that coordinate the media gateway functions.The amount of functionality is based on the particular enabling products used.

For calls that originate and terminate within the domain of the voice over IP network, only a media gateway controller might be needed to complete calls. However, a VOIP network is frequently connected to the public network. In a scalable voice over IP network, you can breakup the role of a controller into signaling gateway controller and media gateway controller. You could use a signaling gateway controller to directly connect to the SS7 network, while also interfacing to a VOIP network elements. This signaling controller would be dedicated to the message translation and signaling needed to bridge the PSTN to the voice over IP network.

There are several protocols and implementations that any number of vendors could deploy. Knowing the details of how the devices use their suite of protocols is important to designing the IP backbone that is to service the voice over IP elements. The services of these devices are defined by the protocols and software they are running.

You can view a VOIP network as one logical switch. However, this logical switch is a distributed system, rather than that of a single switch entity; the IP backbone provides the connectivity among the distributed elements.

Jim Francisto
voip

Accelerator products can help enterprises a lot in addressing the performance requirements of all enterprise applications including Voice over IP. First, Accelerators change the economics of wide area networking by squeezing an average of 100% - 400% more bandwidth with peaks of 1000% depending on traffic mix. This frees up link bandwidth to support high quality service - and it does it without expensive WAN upgrades.

It is also worthy to note that Accelerators do not actually use lossy compression schemes that might degrade voice quality and they add less than one millisecond of latency. In fact, the Accelerator’s compression actually reduces end-to-end latency by reducing serialization delays on WAN links. For example, it takes 125 ms to serialize a 1,000 byte packet on a 64 kbps link, but if an Accelerator increases the effective bandwidth by 4X to 256 kbps, the serialization delay is reduced by a factor of four to 31 ms. The following formula can be used to calculate the serialization delay for any combination of packet size and link speed:

Packet Size (in bytes) x 8 / Link Speed (in kbps) = Serialization Delay (in ms)

In addition to freeing up the bandwidth normally consumed by data applications, Accelerators are able to reduce WAN bandwidth requirements for different voice over IP codecs. In fact, tests have shown that Accelerators reduced G.711 bandwidth requirements by 20% and G.729 by 70%. As a result, WAN links can carry more simultaneous voice calls and the performance of other applications may also be improved.

Accelerators solve increased jitter and latency caused by large data packets over slow WAN links by fragmenting large data packets and injecting voice over IP packets at regular intervals. This feature allows Voip and data to co-exist even on branch office WAN links. For example, normally, a voice over IP packet “stuck” behind a 1,500 byte packet on a 64kbps lin will be delayed by 188ms.

Using the Accelerator’s packet fragmentation will result in the data packet being reduced in size (accelerated - say from 1500 bytes to 500b bytes) and then fragmented into smaller data packets (say - 2 packets of 250 bytes each). In this case, the latency for the Voip packet will go down from 188 ms to 31ms! In addition to increasing WAN capacity for both data and Voice over IP while reducing latency and jitter, Accelerators also manage WAN bandwidth to ensure that critical applications like voice over IP get the bandwidth they need.

Accelerators include an Instant QoS feature that prioritizes application access to WAN bandwidth. Without such prioritization, the additional effective bandwidth provided by Accelerators could be consumed by aggressive, non-critical applications such as file sharing. Accelerator’s AppView feature provides graphical visibility for all application traffic sharing a link. AppView can be used to monitor WAN utilization and to plan future capacity requirements.

And finally, Accelerators have a set of data integrity features that are designed to stop the packet loss that can degrade voice quality. A flow control mechanism reduces packet loss caused by link congestion and a packet recovery feature ensures that any lost packets are transparently recovered at the link level before they can cause voice quality problems.

Jim Francisto
reverse lookup cell phone numbers

You can determine how much bandwidth to set aside for voice traffic using simple math. However, in a converged voice and data network, you have to make decisions on how much bandwidth to give each service. These decisions are based on careful consideration of your priorities and the available bandwidth you can afford. If you allocate too little bandwidth for voice service, there might be unacceptable quality issues.
Another consideration is that voice services are less tolerant to bandwidth depletion than that of Internet traffic. Therefore, bandwidth for voice services and associated signaling must take a priority over that of best-effort Internet traffic.
If a network were to use the same prevailing encoding (CODEC) scheme as the current PSTN system, bandwidth requirements for Voip networks would tend to be larger than that of a circuit-switched voice network of similar capacity. The reason is the overhead in the protocols used to deliver the voice service.
Typically, you would need speeds of OC-12c/STM-4 and higher to support thousands of call sessions. However, IP networks that employ compression and silence suppression could actually use less bandwidth than a similar circuit-switched network. The reason is because of the greater granularity in bandwidth usage that a packet-based network has in comparison to a fixed, channel size TDM network.

Allocations of network bandwidth are based on projected numbers of calls at peak hours. Any over-subscription of voice bandwidth can cause a reduction in voice quality. Also, you must set aside adequate bandwidth for signaling to ensure that calls are complete and to reduce service interruptions. The formula for calculating total bandwidth needed for voice traffic is relatively straightforward. The formula to calculate RTP bearer voice bandwidth usage for a given number of phone calls is as follows:

Bits per sec = packet creation rates per sec x packet size x number of calls x 8 bits per sec

Where samples per sec = 1,000 ms / packet creation rate

Example: 2,000 full-duplex G.711 encoded voice channels that have a packet creation

Rate of 20 ms, with a packet size of 200 bytes (40 byte IP header + 160 byte payload)

50 samples per second = 1,000 ms / 20 ms

160 Mbps = 50 x 200 x 2,000 x 8

Note that this number is a raw measure of IP traffic and does not take in account the overhead used by the transporting media (links between the routers) and data-link layer protocols. Add this raw IP value to that of the overhead to determine the link speeds needed to support this number of calls. Note this value represents only the bearer (voice) content. Signaling bandwidth requirements vary depending on the rate at which the calls are generated and signaling protocol used. If a large number of calls are initiated in a relatively short period, the peak bandwidth needs for the signaling could be quite high. A general guideline for the maximum bandwidth requirement that an IP signaling protocol needs is roughly three percent of all bearer traffic. Using the previous example, signaling bandwidth requirements if all 2,000 calls were initiated in one second would be approximately 4.8 Mbps (3 percent of 160-megabits).

With the calculation of bearer and signaling, the total bandwidth needed to support two thousand G.711 encoded calls would be an approximate maximum of 164.8 MB. This bandwidth requirement is a theoretical maximum for this specific case. If the parameters change, such as call initiation rate, voice encoding method, packet creation rate, employment of compression, and silence suppression, the bandwidth requirements would change as well. With large Voip implementations requiring sizable bandwidth, it becomes imperative that the IP network delivers the needed service at predictably high performance.

Jim Francisto
reverse cell phone look up

Voip sends your phone call through the Internet
A Voip telephony router is a very small device that is used by the majority of Voip telephony users to make IP phone calls. One of the main differences between traditional telephones and Voip telephony is that traditional phone signals are analogue and are sent physically through wires. Voice over IP sends a digital signal and sends it as packet data through the Internet. Therefore, for a person to continue to use the same phone that they have always used for voice over IP calls, they need a device to convert their analogue signal to a digital signal. This is what the Voip telephony router is designed to do.

Voip telephony technology is advancing rapidly
Digital phones allow Voip telephony users to plug directly into their Internet connection or their computer to make telephone calls, thus eliminating the need for a router. Furthermore, it will only be a matter of time before our homes are fully networked for Internet access in every room, thus making Internet phone calls easier and the delivery of other services that will soon be provided through the Internet.

Make your move to Voip telephony as soon as possible
Voip telephony is the telephony of the future. This is indicated by how the large traditional phone companies have all converted over to this technology. What you can expect with a switch to Voip telephony is much lower telephone bills and the closest communication with long-distance family members and loved ones than you have ever known. When they say that the world is getting smaller, it can now truly be seen.

Voip telephony is easy
Although many people fear new technologies or are slow to convert over to a new way of doing things because they are so comfortable with the old, Internet phone calls is something that you should switch over to without hesitation. Of course, the Voip telephony company that you choose to work with is your decision. Just understand that any switch to Voip telephony is better than not switching. For those that hate new devices and new gadgets, a Voip telephony router makes everything so simple and easy to use. Basically, a Voip telephony router will have a socket for you to plug your phone into and another socket for you to plug your internet connection in to. Once you plug in those two things, you will never have to think about your VoIP router again. Now, that is simplicity!

Jim Francisto
reverse cell phone lookup

VoIP products are available from many vendors and range from simple vop phones to complex routers and controllers. VoIP 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 that much about a VoIP products. What are they, how do they work? Here is some information that can help.

VoIP products can be classified in three general categories:

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

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

Hardware and software vop phones
There are two types of vop 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. vop 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.

VoIP 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 VoIP systems. These systems can provide APIs to extend vendor-provided or user-written features and functionality.

VoIP Routers
Routers are (voip) devices that decide where the IP datagrams should go, between networks, from the source to the destination. 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 priorization is in order to ensure good voice quality across the path.

VoIP 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 VoIP systems. These systems can provide APIs to extend vendor-provided or user-written features and functionality.

Jim Francisto
reverse lookup cell phones

To keep your traditional PBX phone system or toss everything out in favor of a Internet Telephony system?

Why to refuse services which would promise to enhance the productivity?
Replace it all for a modern Voice over IP phone system and take all the advantages this relative new technology provides.

What to do?

You can decide whether to have:
- analog,
- digital, or
- IP phones
on your desk and whether to go with TDM or VoIP to be linked with the outside. With some systems you’ll be able to mix.

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

Most phone systems give you the option on how to connect to the PSTN or Public Switched Telephone Network.

A pure Internet Telephony phone system entirely operates in the Internet world from handset to call termination. The equivalent to the traditional PBX is the Voip PBX. The Voip PBX is mainly a software running on a Linux system. Handsets are referred to as SIP phones.
SIP is a switching protocol that controls the phone calls on packet based networks. Calls between subscribers of the same Internet Telephony service provider never leave the network and never enter the PSTN or Public Switched Telephone Network. Calls to and from non-subscribers are terminated to the PSTN at the location of the provider.

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

In general newer Voip PBX phone systems offer a wider range of handset and phone service connection options than legacy PBX systems. But before you make any big purchases or plans to replace you current phone system, you may ask a skilled expert or search for related information in one of the many Voip Review Sites you’ll find on the Internet.

Jim Francisto
VoIP PBX Hybrid
Free Online TV
VoIP Blog

Voip 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 device is. What is it, how does it work?
Here you will find some information aboujt devices.

A 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 Voip 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.
  

Gateway
A Voip 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 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.

Routers
Routers are devices that decide where the IP datagrams should go, between networks, from the source to the destination. 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.

Voip 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 Voip systems. These Voip systems can provide APIs to extend vendor-provided or user-written features and functionality.

Jim Francisto
Voip
Free Online TV