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You can determine how much voip 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 voip bandwidth to give each service. These decisions are based on careful consideration of your priorities and the available voip bandwidth you can afford. If you allocate too little voip bandwidth for voice service, there might be unacceptable quality issues.
Another consideration is that voice services are less tolerant to voip bandwidth depletion than that of Internet traffic. Therefore, voip 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, voip 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, Voip networks that employ compression and silence suppression could actually use less voip bandwidth than a similar circuit-switched network. The reason is because of the greater granularity in voip bandwidth usage that a packet-based network has in comparison to a fixed, channel size TDM network.

Allocations of network voip bandwidth are based on projected numbers of calls at peak hours. Any over-subscription of voice voip bandwidth can cause a reduction in voice quality. Also, you must set aside adequate voip bandwidth for signaling to ensure that calls are complete and to reduce service interruptions. The formula for calculating total voip bandwidth needed for voice traffic is relatively straightforward. The formula to calculate RTP bearer voice voip 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 Voice over 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 voip 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 voip bandwidth needs for the signaling could be quite high. A general guideline for the maximum voip bandwidth requirement that an IP signaling protocol needs is roughly three percent of all bearer traffic. Using the previous example, signaling voip 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 voip 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 voip bandwidth requirements would change as well. With large Voip implementations requiring sizable voip bandwidth, it becomes imperative that the IP network delivers the needed service at predictably high performance.

Jim Francisto
reverse lookup cell phones

Posted under Computers and Technology

Although best known for it’s powerful graphics computers and massive servers, Silicon Graphics regularly produces related pieces of high technology. Back in 1998, Silicon Graphics gave the monitor industry a wake up call by launching the ground breaking 1600SW monitor.

The Silicon Graphics 1600SW is a TFT monitor with a resolution of 1600×1024. It was, and remains, the only monitor to offer a full 16:10 aspect ratio, allowing precise work for computer effects artists, as well as being able to display two A4 pages of text side by side. The 1600SW won several awards for it’s innovative design, and the monitor’s brightness and high resolution still places it at the top end of monitor design, over a decade later.

The monitor used the all digital OpenLDI interface, which required custom graphics cards. Several models of Silicon Graphics machine had the required connector either builtin, or available as an add-in card. Companies like 3D Labs also produced dedicated graphics cards with the special connector, allowing the 1600SW monitor to be used with standard PCs.

Since it’s introduction, many companies have also manufactured convertors, allowing DVI video cards to be used with the OpenLDI interface. Over a decade after it’s introduction, the Silicon Graphics 1600SW remains a high quality monitor that is very sought after by graphics artists.

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Companies of any size are now outsourcing for tasks that can be accomplished by data entry services at home. It not only saves them money, it is better for you if you want to reach out to those who need your services. If you are in the process of starting a data entry services company, you will be working on a business to business basis. It makes no difference if you are working on your own with no employees. As an individual, you outsource when you buy anything for your office that you cannot make yourself such as supplies. Data entry is one of the most popular forms of outsourcing you will find today.

Responsible for the Treasure

When you open a data entry services company for yourself, you are asking to be put in charge of the most treasured commodity that a company possess. The data makes the company what it is and dictates how products and services are marketed, keeps track of customer information, is used for tax purposes and can even be trade secrets to their success. Companies who outsource for data entry services are looking for detailed and organized firm to meet their needs. Data Systems

The In and Out

The key to data entry is to understand that not only are you outsourcing your services, you may need to hire outsource companies to help with your business. When things grow, more time will be needed for payroll and for increase in projects. This means that you will begin to outsource work to make up for the extra work. Take care of the little people and you will be rewarded for it as they will do an extra special job for you.

Data Entry Services Offered

When you venture out into the world of business, it is important to decide what speciality or expertise you want to offer. Trying to do too much or things you have no experience in can be a disaster for businesses. You may choose to work with colleges, doctors and hospitals, marketing companies, local newspapers and media, or insurance companies. The opportunity is out there for a profitable business. The key is to be ready to work and have all the tools you need within reach. Data Storage

The Tools of The Trade

Before you begin to offer services to the community and around the internet, you will need a few tools to make sure you can do the job properly. The first thing you need is a computer with a secure and reliable internet service. You will also need a good knowledge of grammar, spelling, and writing. When starting your own data entry business, you will need to learn the tax rules that come with starting a business and when you begin to hire others, you will know he right procedure to follow. Also check with local and state officials to see what licenses and fees they may need for you to have. These aside, the data entry services business is a great way to stay at home and provide for you. Data Storage

Posted under Computers and Technology