Voice Over IP (VoIP) Telephone Systems
What is all the hype about VoIP?
Voice over IP (VoIP) has been the big buzzword and bandwagon in telecom since dot com and the millennium.
- Telephone carriers like VoIP because it costs them less to provide dialtone and provide long distance.
- Telephone public utilities lke VoIP because they can abandon the high cost of copper maintenance.
- PBX manufacturers love VoIP because it costs them less to produce and develop with less inventory.
- Equipment sellers love VoIP because customers will pay a premium for what they think is newer and better.
- Customers love VoIP because:
- Allows offsite users.
- Allows linking of multiple phone systems with much less cost.
- Gives the full power of the "company" telephone to the remote user.
- Can significantly lowers monthly dialtone andtoll costs.
Does Parker and Toshiba do VoIP or TDM? We both do both! Our IPedge (premise VoIP) and VIPedge (CLOUD VoIP) platforms are 100% VoIP. Toshiba's CIX platforms is both Digital and VoIP in any mixture.
Ask Parker Communications to analyze your particular application to see if VoIP or non-VoIP or some combination of the two makes the most sense for your business. Note that all 3 Toshiba platforms can network together into one large multi-site system
What is VoIP? VoIP (voice over internet protocol) uses your computer data network and the internet to connect the phones to the phone system or the phone system to other phone systems. VoIP can also connect your system to the phone company using SIP trunking. SIP trunking is usually delivered on a data circuit that allows you to get internet and phone service on the same circuit.
What is the alternative to VoIP? Before VoIP, the leading business PBX manufacturers and the telephone companies (Telco) used dedicated TDM digital circuits between them. This allowed perfect "hear the pin drop" digital speech. What was transmitted was heard at the other end immediately and perfectly. Each Digital phone uses its own cable that already exists in most all office buildings with perfect quality and a bad cable or equipment can not take other phones down.
Should we buy a VoIP system? VoIP is the definately the diretion the industry (and Toshiba) are going in. VoIP PBX Phone systems are generally just a pc/server running a software program vs the traditinonal industrial modular electronics based Digital TDM phone system (Toshiba's CIX platform continous this today.
| VoIP System Good Points | VoIP System Bad Points |
|---|---|
| + Faster/Easier Development of new features an apps. + Less physical installation. + Move physical phone to move extension. |
- Full PC operation system exposed to internet a target for hackers. - Requires annual maintenance fees to factory. - Requires Cat5e or better data cabling. - Sharing voice on data on one cable very risky. - Sold system often has no resale as licensing lost and pc old. - Power Backup required in multiple places. |
| Digital/TDM System Good Points | Digital/TDM System Bad Points |
|---|---|
| + Phones work on any grade cable. + PBX Supplies all power to phones and backup and can last days. + No or smaller annual fees. + Perfect Voice and phones can't be taken down by network. + System can last 3-4 longer than a pc based server. |
- Features come slower. - Sold system often has more resale. |
Does VoIP or TDM offer more features? Generally speaking most VoIP systems often basic telecom in a narrow focus. Some while narrow have shiny implemenations of the newest features. The typical non-Toshiba VoIP phone has the standard fixed key features but often have just 2 keys available for Intercom and all other customizable features. Most VoIP providers use SIP (Skinny IP) that is simpler to program but can't do as much as its older brother MEGACO. Toshiba uses Megaco to bring more buttons to each phone. Toshiba's VoIP phone start wtih 10 or 20 programable keys beyond the fixed feature keys. Today Toshiba's user experience of a VoIP phone and a TDM phone are almost the same. Today, when features are too complex for a telephone set, features extend to the users graphical user interface (GUI for PC, Cell, Tablet). However, both VoIP and TDM systems can do this for the power users.
Does VoIP give you better quality speech than TDM?VoIP on its best day can only give 95 percent of what Digital TDM can deliver and many still compress their voice to be that of cellphone quality. There are many pitfalls with VoIP that lower its quality. These pitfalls result in same symptom that cellphones have"choppy speech". These pitfalls can occur on any link of the VoIP chain and are often intermittent, involve many vendors, and can be very expensive to resolve.
How is speech sent? The standard for all telephone speech starts off with sampling the microphone 8,000 times a second and generating a number between 0 and 255. This is 64,000 bits per second or 8,000 bytes per second. TDM guarantees that every one of these bits is sent promptly from one end to the other. Once the call is answered, nothing can interfere with the quality or flow until one of the callers hang up. VoIP takes these 8,000 bytes of information and sends them raw OR uses an algorithm to compress the 8,000 to 1,000 to 4,000 or so. It then sends 20-150 of these bytes at a time with 40 bytes of overhead. This means you need about 84K of up/down bandwidth for corded, TDM sound quality.
With VoIP, the data paths are usually shared. VoIP packets are subject to traffic delays and loss. Since late data is useless it is discarded, resulting in choppy speech. Quality of Service (QOS) internal to your site can be controlled with more expensive data network equipment and support or separate voice and data networks. QOS between sites uses expensive MPLS (requires same data provider) or a large bandwidth. Routers having bandwidth management or separate voice and data neworks are suggested.
Does VoIP really save in cabling costs? Some would say you would save money with a VoIP system when you have to install all new cabling. There is a term "one wire to the desk" where VoIP manufacturers build a mini-switch into the bottom of the phone (Toshiba's have this feature and with a choice of 100MB or GB speed). You would think all you would have to do is plug your PCs into the phone and all would be good. This requires the very latest in quality routers that will route DIFFSERVE and/or the setup of Virtual Lans. Once you start down the VLAN path there is costly switch programming and user discipline is required as the jacks in the switch are no longer all the same. Many top installers of VoIP simply have the customer run 2 data cables so voice and data are separate.
TDM uses almost any twisted pair telecom cable. Most small companies who simply want to move into where another tenant was before, will not have to re-cable with TDM. There can be problems running on "QUAD" cabling. Quad cabling has 4 conductors with out being twisted and has conductors with red, green, yellow, and black coloring. It is NOT a twisted pair cable. It is often found in older buildings or originally installed for alarm systems.
Which is costlier to maintain and/or more reliable? TDM problems are easy to diagnose. There are only 3 things that typically go wrong and only the Telephone vendor is involved. There is no interaction with any other telephone circuit since each path is unique and separate. TDM networking (using point to point PRIs using T1s ) are multi-vendor but have self testing and fault detection built in.
VoIP is much harder and costlier to diagnose. Any device on the network or the Internet can be the problem. All activity of VoIP and non-VoIP equipment can be the source of the issues. There are dozens of interacting intermittent possibilities. There can be lots of equipment, companies, and programming involved. Expensive network assessments costs thousands for a couple of hours of testing that may or may not see your intermittent issue. Lots of finger pointing possibilities exist. Thats why most have a separate data cable and switches for phones.
Power Failures and VoIP: VoIP requires electrical power in many places to work. Each phone needs a power with a cube OR expensive Power Over Ethernet (POE) switches. The PBX, all switches, Routers, ISP edge equipment - they all need electrical power. You must provide battery backup at every location where one of these devices resides.
TDM systems often have a single battery backup device. The PBX supplies power to all of its phones. The phone company powers both TDM analog and digital circuits.
SIP trunking uses VoIP to connect your phone system to a phone company. These can be delivered directly from your particular ISPs that have a Telco division or Hosted in the CLOUD and rides on any internet. It used to be that only the ISP with a built in Teleco division could deliver service without choppy speech. The internet although it still does not have QOS for voice is becoming fast enough to deliver VoIP without choppy speech if both ends are on a large quality internet. Customers using a small pipe will need a QOS router to priorite Voice over Data. Often customers choose to bring in two internets so this box and complexity is eliminated. Comcasts makes having 2 internet pipes affordable.
Toshiba now offers SIP trunk for its customers. Toshiba's data center is on the Top Tier of the internet with a very large pipe. Toshiba allow you automaticly failover each phone number to a different backup number if you wish. It is very economical for a small system that never before could afford direct lines to each phone and department for less than they pay the phone company today and often keep their small Toshiba phone system. Toshiba does NOT compress their SIP Trunks giving you the best quality possible (Most SIP Trunk providers (except Toshiba and Comcast) compress the original 64K stream down to 8 to 28K dropping highs and lows making calls sound tinny. We do not suggest any SIP Trunk service for fax or modems however. Ask our Engineers map out the best choice for your particular needs.
Phone companies, including the local public utility, AT&T, are pushing VoIP to save themselves money at the expense of the quality of your phone service. You may ask for a traditional PRI circuit but may end up with VoIP SIP trunks with an edge device converting it into a PRI look-a-like. Once you reach your phone compnay, a SIP call will most likly be passed to the far end via that company's B network (not as good as their A network (digital 64K TDM - like a PRI)).
SIP trunking is brand new technology. The standard is more like a guideline. Not everyone plays well together. Toshiba has certified the following companies with the Toshiba Phone Systems: American Broadband Services, AT&T, AireSpring, Broadcore, Broadvox, CBeyond, ClearFly, Everest Broadband, Iptimize, Level 3, Line Systems, MM Internet, nTelos, New Global Telecom, PAETEC, POPP.com, Select Connect Communications, Smart Choice, SoTel Systems, TelePacific, Twist Networks, Xchange Telecom, and XO Communications.