ITELEC IT, COMMUNICATIONS AND ELECTRICAL

Gold Coast Data and Electrical Specialists

 

07 5522 2222


Telecommunication FAQ's
Q: What is ADSL?

A: ADSL Asymmetric Digital Subscriber Line, or DSL for short is a high-speed Internet access service that utilizes existing copper telephones lines to send and receive data at speeds that far exceed conventional dial-up modems. The fastest dial-up modems are rated at 57 kilobits per second and usually operate at about 53 Kbps under good conditions. By comparison, ADSL allows datastream speeds from 1.5 to 8 megabits per second depending on the grade of ADSL service purchased. ADSL uses standard telephone lines to transmit upstream and downstream data on a digital frequency, which sets these datastreams apart from the analog signals telephones and fax machines use. Because the ADSL signal is operating on a frequency that is inaudible to humans, the telephone can be used normally, even when surfing the Web with the ADSL service.

 

Q: What is BDSL?

A: BDSL Business Digital Subscriber Line is the business equivalent of ADSL. The primary difference is the quality of connection and the restoration time in the event of an outage.

 

Q: What is BD?

A: Building Distributor (BD) is the primary place of connection between the network and the building cabling.

 

Q: What is a Carriage Plan?

A: A Carriage Plan is a schedule of call costs offered by  carriage providers. Carriage Plans usually offer significant savings on normal rates and are offered on a fixed term contract of 2, 3, 4 or 5 years.

 

Q: What is a CD?

A: CD is a Campus Distributor or Intermediate distribution Frame

 

Q: What is CPE?

A: Customer Premises Equipment, or CPE for short, is the telecommunications equipment, including PABX’s and wiring, located within a customers premises.

 

Q: What is CPU?

A: Central Processing Unit. The CPU is the main brain of the computer or telephone system.

 

Q: What is DSL?

A: Digital Subscriber Line, or DSL for short is a high-speed Internet access service that utilizes existing copper telephones lines to send and receive data at speeds that far exceed conventional dial-up modems. The fastest dial-up modems are rated at 57 kilobits per second and usually operate at about 53 Kbps under good conditions. By comparison, DSL allows datastream speeds from 1.5 to 8 megabits per second depending on the grade of DSL service purchased. DSL uses standard telephone lines to transmit upstream and downstream data on a digital frequency, which sets these datastreams apart from the analog signals telephones and fax machines use. Because the DSL signal is operating on a frequency that is inaudible to humans, the telephone can be used normally, even when surfing the Web with the DSL service.

 

Q: What is a Fixed Cellular Terminal?

A: A fixed Cellular Terminal or FCT for short is a device that allows a mobile phone to be connected to your PABX phone system. The FCT appears as an outgoing line and allows calls from your phone system to be routed via the mobile network. The installation of an FCT can save considerable phone call costs when used with the correct Carriage Plan.

 

Q: What is an IDF (aka FD)

A: IDF stands for Intermediate Distribution Frame. In a larger building the MDF would connect to one or a number of IDF’s for instance a 10 story apartment block might have an MDF on the ground floor and an IDF on each other floor. It can also be called a BD (building Distributor) or FD (floor distributor). See diagram.

 

Q: What is IP Telephony?

A: IP telephony is the use of VoIP either internally within your office environment or over the internet.

 

Q: What is ISDN?

A: ISDN stands for Integrated Subscriber Digital Network. Telstra is relying more and more on ISDN connections to businesses. ISDN connections use one pair of wires to provide two separate channels of speech (PSTN needs one pair of wires for each channel of speech) thereby halving the number of wires that they need in the street. ISDN sends digital pulses along the cables if you were to connect a listening device along an ISDN line you would only hear electronic ‘chatter’. In most cases you need a PABX at the end of this connection to decode the intelligible digital signals back to voices. ISDN is also used to send data and video signals between locations

 

Q: What is Least Cost Routing?

A: Least Cost Routing or LCR for short is programming within your telephone system to allow outgoing calls to access the cheapest path of connection. For instance you might have a Mobile phone plan which allows you to call within your ‘fleet’ of mobiles for free. By installing a Fixed Cellular Terminal and LCRing via this device the calls from your phone system to your mobiles is free.

 

Q: What is an MDF

A: MDF stands for Main Distribution Frame. This is where the incoming telephone lines from the street terminate within a building. Depending on the size of the building the MDF could be a small plastic box on the wall or a large room. It can also be called a CD or Campus distributor. See diagram

 

Q: What is an MFU

A: MFU stands for Multi Function Unit. This is Ericsson device that includes 8 digital extensions, 4 analogue extensions, 4 ISDN2 connections and VoiceMail.

 

Q: What is PSTN?

A: PSTN stands for Public Switched Telephone Network. The Telstra network that you use each day is a PSTN network. The Telephone that you use at home is most likely a PSTN phone. PSTN connections use one pair of wires for each telephone or channel of speech. If you connect a listening device anywhere along the line leading to your house you would be able to hear the conversation. PSTN is an analogue network.

 

Q: How long does it take to get a new phone system?

A: In some instances new systems can be installed in a couple of days. However there are a number of issues that have to be addressed prior to the installation of a new telephone system. Most new systems use ISDN lines instead of the old PSTN connections. The provision of these lines can take up to 10 days and longer. Some systems (especially if you have chosen a campaign purchase) are delivered directly from the manufacturer which may add as much as four weeks to the installation time. ITELEC holds large quantities of stock thereby minimizing this type of delay.


Q: How many phone lines should I have connected to my new phone system?

A: The number of phone lines required for you business depends on the type and size of business that you run. As a general rule the following apply: Outbound Call Centre 1 line for each operator Inbound Call Centre 1 line for each operator Accommodation Building 1 line for each 8 units Small to Medium business 1 line for each 3 employees Obviously numbers may vary according to circumstances.

 

Q: What is VoIP and how does it work?

A: VoIP is a technology that gives you the ability to make a voice phone call over an IP network such as a Local Area Network or the Internet. The technology has been used for many years at big business level enabling remote branch offices being able to use the capacity of their computer network to also carry voice calls. The technology is now available to small/medium business to implement using the Internet to transmit phone calls at a greatly reduced cost compared to traditional telephone networks. Your PABX turns voice data into a form that is transmitted via IP and reassembled at the receiver's PABX.


Q: Is VOIP reliable?

A: Conventional telephones are connected directly to Telstra infrastructure. In the event of a power failure these phones are kept functioning by generators and batteries located at the telephone exchange. Business telecommunications hardware is invariably powered locally. A power failure will stop this equipment from operating unless you have an Uninterruptible Power Supply (UPS) or back-up generator. This applies to VoIP equipment as well. Even with local power still available, the broadband carrier itself may experience outages. While the conventional telephone network has matured over decades and is extremely reliable, most broadband networks are less than 10 years old, and even the best are still subject to intermittent outages. Furthermore, consumer broadband connections such as cable and DSL often are not subject to the same restoration service levels as the conventional telephone network. Whilst VoIP is becoming an important business technology it should not be used without redundant facilities.


Q: What is Quality of Service and why is it so important?

A: QoS is the ability to program what types of data are given priority through your broadband connection (normally controlled by your router or programmed into the VoIP equipment). During a VoIP conversation your voice "packets" need to have priority over data using the same network to ensure there is no "latency" (delay from when you speak and the other person hearing you) or "packet loss" (voice cutting out). It ensures the best possible quality for your voice conversation. QOS is an important--perhaps the most important--consideration for businesses moving to Internet telephony. That's because, for more than a century, businesses have generally taken telephone QOS for granted. Enterprises that switch to a low-cost VoIP service are often surprised to discover that they have entered a world where service quality can be elusive and hard to achieve. The shortcomings are manifold. Latency, packet loss, network jitter (data arriving out of order) and numerous other factors can all degrade a voice connection's quality, leading to distorted audio, disconnects and even total VoIP system collapse. Since few enterprises wish to subject their employees and clients to poor phone call quality (or QOS), it's critical to pay close attention to service quality issues when designing a VoIP system. Despite a widespread perception to the contrary, VoIP actually has the potential to deliver a higher QOS than the public switched telephone network (PSTN). In fact, if bandwidth and system costs weren't an issue, everybody would be enjoying phone calls with CD quality audio. In the real world, however, enterprises and end users would be happy to settle for low-bandwidth, yet clear, glitch-free calls. Fortunately, such a goal is attainable for the enterprise that's willing to take QOS seriously and not cut corners.


Q: What are the things that affect my VoIP Quality of Service (QoS)?

A: A variety of problems can affect VoIP Quality of Service, including dropped packets (too much data arrives at the receiving server too quickly), packet delay (data takes the long way around the Internet), jitter (different packets reach the receiver at different times) and related out-of-order delivery, and other mishandling of the data packets themselves. Each problem causes delays, which in time-sensitive settings like voice leads to lowered voice quality or even the dropping of whole calls.


Q: What is latency and why is it important on a VoIP Network?

A: Latency is the length of time it takes for your words to be received by a listener at the other end of a phone connection, typically expressed in milliseconds. Latency starts to affect phone conversations when it exceeds 150 milliseconds each way, and is unacceptable when it exceeds 450 milliseconds (nearly half a second).


Q: What are some ways to measure the performance of a VoIP network?

A: Latency is the total of a lot of small delays that occur during the coding, transmission and decoding of a voice conversation. The time each step takes can be measured, and then improved through better network equipment and better configuration of the network. Performance factors within a business's control include the presence of absence of a firewall for VoIP traffic; delays in the digital signal processor (DSP) that codes and decodes voice traffic; how big a chunk of data the DSP takes on at once; how big a buffer you build in against delays elsewhere in the VoIP system; and how efficiently the decoded signal is routed within your data network to an IP-enabled phone or PC. Performance factors outside a business's control include the length of the path packets travel between computers across the Internet, and the speed at which signals travel through physical lines or satellite links (typically a high fraction of the speed of light).


Q: What is SIP?

A: Session Initiation Protocol (SIP) is a set of standards that helps create, change and end IP sessions between one or more users, such as in the case of VoIP calls or audio conferences. It is notably lightweight and transport-independent, and was designed by the IP-community programmers rather than by the telecom industry.


Q: What is A Video Conference?

A: A Video Conference is a means of Communication across long distances with video and audio contact that may also include graphics and data exchange. ITELEC provides public Video Conferencing Facilities from its Offices at Varsity Lakes on the Gold Coast. See the Video Conferencing glossary here