Introduction to Telecommunication

Equipment 101

or

How to Select Telephone Systems & Services to Fit

Your Needs

Bill BrackinProgram Director, North Sound 2-1-1

And Telephone Systems ManagerVolunteers of America Western Washington

•Telephone Services•Dial Tone•Long Distance•Networking•Managed Services

•Telephone Systems•Centrex with Single Line Phones

•Software as a Service with Single Line Phones

•Switches

•Digital Switch

•VoIP Switch

•PBX & IP PBX

•Optional Special Features

Telephone Services– Dial Tone - POTS Lines

POTS = “Plain old telephone service”

POTS lines are the simplest telephone line you can buy.

They are often referred to as “business lines”. Even in complex applications POTS lines have their place. They provide backup lines, fax lines, and other simple applications. They are usually delivered as analog lines.

Telephone Services– Dial Tone – T Carrier Lines

T1 means any data circuit (including voice packets) that runs at the 1.544 Mb/second line rate. T-1’s are point-to-point digital lines that can have multiple unique numbers (DIDs) assigned. Each T-1 is a dedicated leased digital line that is connected to a Private Branch Exchange (PBX) from the central office (CO). Features are provided by your telephone system.

T2 and T3 circuit channels carry multiple T1 channels multiplexed, resulting in transmission rates of 6.312 and 44.736 Mbit/sec, respectively.

• Telephone Services– Dial Tone – T Carrier Lines

• T1s come in a couple of versions– T1, which has 24 paths for incoming and/or

outgoing traffic.

– T1 PRI, which in North American includes 23 voice channels + 1 data channel. The D channel carries control and signaling information, including caller ID.

– Fractional T1 - 256, 348, 512, 768 Kbps services providing less than 23 voice channels.

• Telephone Services–Dial Tone - Hosted Telephony

- Pay by the month or by the call- Less equipment on premises- In the “cloud”, and managed by the vendor- Vendor manages any equipment that is located on

your premises, and you rent that equipment as part of

the by themonth or by the call cost.- Benefits may be reduction of cost, flexibility, built-

inbusiness continuity, and advanced applications.

• Telephone Services– Long Distance Services – 3 Classes

In the United States, long distance can refer to three different classes of calls that are not local toll-free calls. The most common class of long-distance is often called interstate long-distance, though the more accurate term is inter-LATA interstate long distance.

Another form of long-distance, increasingly relevant to more U.S. states, is known as inter-LATA intrastate long distance. This refers to a calling area outside of the customer’s LATA but within the customer's state.

Often, in large LATAs, there is also a class known by the oxymoronic name local long distance, which refers to calls within the customer's LATA but outside of their local calling area. This is sometimes also referred to as intra-LATA long distance.

• Telephone Services– Long Distance Services – Purchasing

Before buying any long distance services make sure you know what rate will be charged for each of these three categories. Intra-LATA calls can legally be billed at a much higher rate than are Inter-LATA calls, and often are. This may be a point of negotiation.

It is also very important to know the approximate minutes of each of these categories of calls that your agency makes, so that you can evaluate the financial impact of a long distance proposal on your agency specifically.

You can buy long distance services from your dial tone provider, or anyone else you want to do business with. You will need to tell your dial tone provider which long distance carrier you are going with, because they need to program that into their systems.

• Telephone Services– Long Distance Services – Slamming and PIC

Freezes

“Slamming” is the illegal practice of changing a consumer's telephone service—local (intra-LATA), toll (inter-LATA intrastate), long distance (inter-LATA inter-state), or international—without permission.

To prevent slamming you can arrange in advance with the local exchange carrier (local telephone company) to initiate a “PIC Freeze” to prevent unauthorized changing of the long distance telephone carrier. It stipulates that your carrier may not be changed without your written consent. This feature is free of charge. If in the future you want to change carriers, remember to submit a written request to remove the PIC Freeze before placing your change order.

• Telephone Services– Networking

If you plan on tying together multiple locations into a common telephone and/or data system, you will need to design a networking system.

Your specific telephone system may dictate the options that you have available to you. Some systems won’t work well with DSL networks, for example. Some work very well with them.

Networking is a very technical area, and your IT staff or consultant should help you make this choice. Don’t be afraid to ask lots of “dumb” questions. This is complicated stuff, and each option comes with good and bad features, security considerations, installation and operational costs, maintenance and support issues, and more.

• Telephone Services– Networking

• Here are some, but not all, of the many items to consider:– Is your telephone system VoIP capable or not?– Size of the data packets that your VoIP telephone system sends across

the network.– The reliability of each type of networking service.– Is the proposed network “point-to-point”, “cloud”, or some other design?– Who manages the maintenance, security, and upgrades?– Do you need to purchase the routers, or are they provided as part of the

service?– Does your telephone system have the capacity to add the networking

service, and if not, what will it cost to add that capacity?– How long of a contract must you sign in order to get a reasonable price?– Is the provider using “compression”, and if so, how much?– Can the vendor give you access to existing customers who are using the

proposed system in a similar way to what you are proposing?

•Telephone Services

Managed services is the practice of transferring day-to-day related management responsibility as a strategic method for improved effective, efficient, and cost effective operations. The person or organization who owns or has direct oversight of the organization or system being managed is referred to as the offerer, client, or customer. The person or organization that accepts and provides the managed service is regarded as the service provider.

Typically, the customer remains accountable for the functionality and performance of managed service and does not relinquish the overall management responsibility of the organization or system.

Centrex lines are analog lines provided by the local telephone service provider that provide programmable features on the line. The cost is based on usage and features programmed for each line and monthly service fee. Hardware and software maintenance is included in the monthly costs. No technical staff is required to operate such a system. Agents can easily be set up to work from home.

• Telephone Systems–Centrex with Single Line Phones

Local Central Office (CO)

Call Center or Agency

Switching Software is

Located Here

Agent at Home

“Software as a Service” rides on analog or digital lines provided by the local telephone service provider. It includes additional routing, call center management, voice mail, etc. provided by a different provider than your local telephone company. The cost is based on usage and features programmed for each line and a monthly or per-call service fee. Hardware and software maintenance and upgrades are included in the monthly costs. There may be an initial setup fee. No technical staff is required to operate such a system. Agents can easily work from home, and center can easily be relocated during emergencies and disasters.

• Telephone Systems–Software as a Service with Single Line Phones or Telephone Systems

SAAS Provider Switch (s)

Call Center or Agency

Switching Software is

Located Here

Agent at Home

Local Central Office (CO)

•Telephone Systems–Switches

A telephone switch is a system of electronic components that connects telephone calls. It is hardware that is controlled by software in modern telephone systems. In the past switching was often done manually.

A switch can be located in a local or long distance telephone company’s office or on your premises. Telephone switches are a small part of the large telephone network. When a switch is in-house, it is often referred to as the telephone system or PBX (Private Branch Exchange). In-house switches require you to pay for maintenance and hardware and software upgrades as needed. They are more challenging to set up for at-home agents, and are not as easily relocated during emergencies or disasters. They usually need you to hire technical staff or to contract with a maintenance provider to make changes, upgrades, or maintenance. In large agencies, where IT staff is already available, they may provide a lower cost solution.

• Telephone Systems– Digital Switch

A digital switch is a type of switch that connects two or more digital circuits together. It is a type of switch that has been used by telephone companies, agencies, and businesses for a long time. They operate on time tested and reliable telephone engineering. If you have a switch that is six or more years old, you probably have a digital switch.

• Telephone Systems– VoIP SwitchVoice Over Internet Protocol (VoIP) refers to

communications services—voice, facsimile, and/or voice-messaging applications—that are transported via the Internet, rather than the public switched telephone network (PSTN). The basic steps involved in originating an Internet telephone call are conversion of the analog voice signal to digital format and compression/translation of the signal into Internet protocol (IP) packets for transmission over the Internet; the process is reversed at the receiving end.

• Telephone Systems– VoIP Switch

Other terms frequently encountered and synonymous with VoIP are IP telephony, Internet telephony, voice over broadband (VoBB), broadband telephony, and broadband phone.

Because these systems connect telephones and switches by way of the Internet, they are typically easier for IT staff to deal with than digital switches. They do require firewall security systems, as do computer networks.

• Telephone Systems– VoIP Switch – Quality of Service

Considerations

The underlying IP network is inherently unreliable, in contrast to the circuit-switched public telephone network. It does not inherently provide a mechanism to ensure that data packets are delivered in sequential order or provide Quality of Service (QoS) guarantees. Because of this VoIP implementations face problems mitigating latency and jitter.

The receiving node must restructure IP packets that may be out of order, delayed or missing, while ensuring that the audio stream maintains a proper time consistency. Variation in delay is called jitter.

• Telephone Systems– VoIP Switch – Power Considerations

Traditional residential and business analog POTS line services are usually connected directly to telephone company phone lines. They provide direct current to power most the basic analog handsets independently of locally available power.

In a VoIP installation you must plan for power and power backups, since the phones, servers, and switches will not work without local power being supplied.

• Telephone Systems– VoIP Switch – 911 Considerations

A fixed line phone has a direct relationship between a telephone number and a physical location. If an emergency call comes to 911 from that number, then the physical location is known.

In the IP world it is not so simple. A broadband provider may know the location where the wires terminate, but this does not necessarily allow the mapping of an IP address to that location.

• IP addresses are often dynamically assigned, so the ISP may allocate an address for online access, or at the time a broadband router is engaged. The ISP recognizes individual IP addresses, but does not necessarily know what physical location to which it corresponds.

• The broadband service provider knows the physical location, but is not necessarily tracking the IP addresses in use.

• Since IP is portable, the location may be a moving target. 911 calls will often mis-locate the caller. This has resulted in known deaths because of responders being directed to an old or incorrect address. It is critical that you maintain tables in your VoIP phone system to locate all extensions.

• Telephone Systems– VoIP SwitchWith all of these considerations VoIP has still

become the standard. Why?– Low cost, especially when combined with Internet,

cable TV, and computer data networking.– Easily transportable. Software can be placed on a

laptop to mimic a telephone set. This is called a softphone.

– VoIP service is nearly indistinguishable from the PSTN.– VoIP phones allow VoIP calls without the use of a

computer. Of course, Internet connectivity is still required.

– VoIP allows for more flexibility and interchangeability of software and hardware in many cases.

• Telephone Systems– VoIP Switch

384k committed rate

256k committed rate

RemoteAgent

Call Center

Full T1 1.544m

Fractional T1512k

Call Center

Call CenterCentral

Office

Central Office

Central Office

Internet Cloud

VoIP – Hardware and software that allows people to use Internet protocols to make telephone calls.

• Telephone Systems– PBX or IP PBX

A private branch exchange (PBX) is a telephone switch that serves a particular business or office, as opposed to one that a telephone company operates for many businesses or for the general public.

PBXs make connections among the internal telephones of a private organization and also connect them to the public switched telephone network (PSTN) via trunk lines like T1s.

PBXs are differentiated from “key systems" in that users of key systems manually select their own outgoing lines, while PBXs select the outgoing line automatically. Hybrid systems combine features of both.

An IP (Internet Protocol) PBX (Private branch exchange) is a business telephone system designed to deliver voice or video over a data network and interoperate with the normal Public Switched Telephone Network (PSTN).

VoIP (Voice over Internet Protocol) gateways can be combined with traditional PBX functionality enabling businesses to use their managed intranet to help reduce long distance expenses, enjoy the benefits of a single network for voice and data and advanced CTI (Computer telephony integration) features or be used on a pure IP system which in most cases give greater cost savings, greater mobility, and increased redundancy.

An IP-PBX can exist as a hardware object, or virtually, as a software system.

• Telephone Systems– Optional Special Features – (will be covered in Telephony 201)

• Automatic Call Distribution (ACD)– Skills Based Routing– Voice, Email, Fax, Chat

• Interactive Voice Response (IVR)– Speech recognition

• Call Center Software• Call Recording• Call Accounting• Voice Mail• Workforce Management (WFM)• Online Hiring Software• Integrated Training Tools• Computer Telephony Integration (CTI)• Work at Home or Remote Agents• Contact Management System (CMS)• And more….

Bill Brackin, Program Director

North Sound 2-1-1(425) 609-2213bbrackin@voaww.org

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