Welcome to Teracom's Online Course 2201: The PSTN
In this course, we'll understand the Public Switched Telephone Network (PSTN), and Plain Ordinary Telephone Service (POTS). Understanding the fundamentals of this technology and network architecture is the starting point for understanding everything else.
This free online telecom training course lesson is the introduction to the course.
The PSTN is the fourth course in the CTNS Certification Package.
Join thousands of satisfied customers including the FBI Training Academy, US Marine Corps Communications School, US Army, Navy, Air Force and Coast Guard, CISA, DISA, DoJ NSD, NSA and CIA, IRS, FAA, DND, CRA, CRTC, RCMP, banks, power companies, police forces, manufacturers, government, local and regional telcos, broadband carriers, individuals, telecom planners and administrators, finance, tax and accounting personnel and many more from hundreds of companies.
Benefit from decades of knowledge, insight and experience distilled into clear lessons designed for non‑engineers, logically organized to build one concept on another... in plain English. Teracom's GSA Contract supplying this training to the US government reflects approved quality and value that you can depend on.
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The TCO Certified Telecommunications Subject Matter Expert (CTSME) is the most comprehensive telecom, datacom, networking, wireless, VoIP and SIP training and certification available anywhere.
CTSME encompasses four TCO Certifications: CTA, CVA, CWA and CTNS. You get all four certifications, with their courses, bundled with a discount in the CTSME Certification Package.
Complete all four to get your Certified Telecommunications Subject Matter Expert credential, including a framed TCO CTMSE Certificate and personal Letter of Introduction for your résumé.
Five TCO Certifications, Five Certificates and Letter of Reference. 30-day, 100% money-back guarantee
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Sixteen online courses covering telecom, datacom and networking for non‑engineers from A‑Z, plus the prestigious TCO Certified Telecommunications Analyst certification.
Includes the eight CTNS courses plus
TCO Certification, Certificate and Letter of Reference.
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These are the words that are displayed and spoken during the lesson. Get these notes for the whole course in the Certification Study Guide, available in print or eBook. Many people tell us a printed companion book enhances their learning!
It is tempting for newcomers to telecom to think "this is old stuff, we don't need to know this, it's all IP now"... but it is not difficult to come up with a list of reasons why understanding POTS and the PSTN is still necessary:
And let's not forget that DSL services – high-speed Internet access over twisted pair – are provided over the infrastructure put in place for POTS.
Whether you are mostly interested in learning about traditional telecommunications, data communications, modern Voice over IP packet networks or cellular, it all begins with POTS.
Cable Vault in the Basement of a Central Office
Lesson 1 is the Introduction to the Course.
Lesson 2 is a brief history lesson, beginning with the invention of the telephone. This will establish the concept of local telephone companies, access circuits and inter-city transmission.
Next, in Lesson 3, we will understand the fundamentals of the PSTN: customer premise and Central Office, loops, trunks, circuit switching and understand how a telephone call is connected end-to-end.
Then in Lesson 4, we will understand how information is represented on the local loop using analog techniques in traditional telephony, and just what exactly we mean by analog.
Lesson 5 is the question of fidelity: how faithfully the voice is reproduced at the far end, which is determined by the frequency bandwidth provided on the access, known as the voiceband. The lesson on the voiceband is available free on the online courses previews page.
Lesson 6: The voiceband, loops, trunks and circuit-switching are all aspects of Plain Ordinary Telephone Service. We'll round out the discussion by understanding some of the other key aspects of POTS and related jargon and buzzwords like "twisted pair".
In Lesson 7, we will then look at an improvement on the address signaling mechanism for POTS that was called "touch tone", or more technically, DTMF.
Finally, in Lesson 8, we will understand in broad brushstrokes the control system for the telephone network, called SS7 in North America, and basic principles of call routing.
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Invest in yourself with Teracom’s CTNS Certification Package, eight online courses delivering a solid foundation in telecom, datacom and networking: understanding the fundamentals, technologies, jargon and buzzwords, and most importantly, the underlying ideas and how it all fits together… plus TCO Certification to prove it:
2241 Introduction to Broadband Converged IP Telecom
2206 Wireless Telecommunications
2221 Fundamentals of Voice over IP
2201 The PSTN
2212 OSI Layers and Protocol Stacks
2211 LANs, VLANs, Wireless and Optical Ethernet
2213 IP Addresses, Packets and Routers
2214 MPLS and Carrier Networks
Benefit from decades of knowledge, insight and experience distilled into clear lessons, logically organized to build one concept on another. Get a major career-enhancing and productivity-enhancing knowledge upgrade – learning that you can't get on the job, reading magazines or talking to vendors.
Based on Teracom’s famous week-long instructor-led BOOT CAMP, the selection of material, its order, timing, and explanations are field-tested to deliver the core up-to-date knowledge set for today’s telecommunications.
The first four CTNS courses are on telecommunications, beginning with Introduction to Broadband Converged IP Telecom, an introduction and first pass through all of the topics; followed by Introduction to Voice over IP, then Wireless Telecommunications, including 5G and Wi-Fi 6, and the PSTN.
Introduction to Broadband Converged IP Telecom is a high-level wide-ranging introduction to the world of modern IP telecommunications.
This course is based on the first chapter of Teracom's famous instructor-led BOOT CAMP, getting a full week of training started with an introduction to all of the different aspects of the modern converged IP telecom network.
Designed specifically for non-engineers, It's a first pass through the topics, starting at the beginning, explaining the fundamental ideas, jargon, equipment and technologies, the services that are sold, the players, where the money is, and how it all fits together.
In subsequent courses, we'll take another pass and drill deeper into key areas like Wireless, VoIP, PSTN, Ethernet, IP and MPLS.
This is quite a range of knowledge, and can appear daunting, especially if you are new to telecom. Keep in mind that this course is the introduction, the first pass through all of these topics.
No-one is expecting anyone to be an instant expert!
In subsequent courses, we take a second and sometimes third pass through the topics and drill deeper to more fully understand the concepts and technologies.
With this course, we're getting started identifying and understanding all of the aspects of modern broadband converged IP telecommunications.
Based on Teracom's famous Course 101, tuned and refined over the course of more than 20 years of instructor-led training, we'll cut through the jargon to demystify modern IP telecommunications, explaining the jargon and buzzwords, the underlying ideas, and how it all works together… in plain English.
We begin with basic concepts and terminology involved in mobile networks, including base stations and transceivers, mobile switches and backhaul, handoffs, cellular radio concepts and digital radio concepts.
Next, we understand how phone calls are made over radio and how they connect to landlines; and how mobile internet is implemented, tethered modems and mobile Wi-Fi hotspots.
Without bogging down on details, we'll review spectrum-sharing technologies: FDMA for first generation; 2G GSM/TDMA, 3G CDMA and 4G and 5G OFDM.
We'll understand how modems represent bits on subcarriers in OFDM, and how OFDMA is used in 4G and 5G to dynamically assign subcarrier(s) to users.
This is followed with Wi-Fi, or more precisely, 802.11 wireless LANs: the system components, frequency bands, bitrates and coverage for all of the versions up to Wi-Fi 6 which is 802.11ax, the first Wi-Fi to implement full-duplex communications with multiple simultaneous devices using OFDMA and a theoretical 9.6 Gb/s.
The course is completed with communications satellites, in Geosynchronous Earth Orbit and Low Earth Orbit, including Iridium Next and Starlink.
You'll gain a solid understanding of the key principles of wireless and mobile networks:
Jargon & Buzzwords • VoIP Phone System Components and Operation • Voice Packetization • LANs and WANs • VoIP Phones: MAC Address, DHCP, IP, UDP, RTP, QoS • SIP, Softswitches & SIP Trunking • Cloud • The Future
Fundamentals of Voice over IP is a complete introduction to everything Voice over IP. You'll learn the fundamental ideas and principles of a VoIP telephone system, VoIP, SIP & all the other jargon - what it actually means and how it all works together.
At each step, we'll also cover supporting and related technologies like Ethernet MAC frames and codecs and video over IP.
The objective of this course is to put in place a solid, structured base of knowledge in the technology and implementation of communicating thoughts from one person's brain to another via a telephone conversation carried in IP packets.
In particular, on completion of this course, you will be able to explain:
One cornerstone of a full, rounded base of knowledge of telecommunications is the structure and operation of the Public Switched Telephone Network, built over the past 135 years, still in operation in every country on earth – knowledge necessary for connecting the PSTN to, and steadily replacing the PSTN with IP telecom technologies.
In this course, you'll build a solid understanding of the fundamentals of the telephone system: Customer Premise and Central Office, loops, trunks, remotes, circuit switching and how a telephone call is connected end-to-end. We'll cover LECs, CLECs and IXCs, sound, analog and the voiceband, twisted pair, DTMF and SS7. Updated for the 2020s.
On completion of this course, you will be able to draw a model of the Public Switched Telephone Network, identify and explain its components and technologies including:
The second half of CTNS is four courses on networking, delivering a practical understanding of Ethernet and its MAC frames, IP packets with IP addresses and routers, and the traffic management system MPLS. We begin with the OSI Reference Model and its Layers as a framework to organize the discussions.
This course establishes a framework for all of the subsequent discussions: the OSI 7-Layer Reference Model, which identifies and divides the functions to be performed into groups called layers.
This framework is required to sort out the many functions that need to be performed, and to be able to discuss separate issues separately.
First, we'll define the term "protocol" and compare that to a standard. Then we'll define "layer" and how a layered architecture operates, and provide an overview of the name, purpose and function of each of the seven layers in the OSI model.
Then, we'll go back through the story more slowly, with one lesson for each of the layers, examining in greater detail the functions that have to be performed and giving examples of protocols and how and where they are used to implement particular layers.
The result is a protocol stack, one protocol on top of another on top of another to fulfill all of the required functions. To make this more understandable, this course ends with the famous FedEx Analogy illustrating the concepts using company-to-company communications, and an analogy of Babushka dolls to illustrate how the protocol headers are nested at the bits level.
On completion of this course, you will be able to:
This course is all about Ethernet: the fundamentals, equipment and implementations including twisted-pair copper cables, wireless and fiber, in-building, in the network core, MANs and PONs.
You'll understand the jargon and buzzwords, the underlying ideas, and how it all works together to form the physical basis of the telecom network.
On completion of this course, you will be able to explain:
On completion of this course, you will be able to explain:
MPLS and Carrier Networks is a comprehensive, up-to-date course on the networks companies like AT&T build and operate, how they are implemented, the services they offer, and how customers connect to the network.
The IP packets and routing of the previous course is one part of the story. Performance guarantees, and methods for quality of service, traffic management, aggregation and integration is another big part of the story, particularly once we leave the lab and venture into the real world and the business of telecommunications services.
We'll begin by establishing a basic model for a customer obtaining service from a provider, defining Customer Edge, Provider Edge, access and core, and a Service Level Agreement: traffic profile vs. transmission characteristics.
Next, we'll understand virtual circuits, a powerful tool used for traffic management and how they are implemented with MPLS, explaining the equipment, jargon and principles of operation.
Without bogging down on details, we’ll cut through buzzwords and marketing to demystify:
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FAQsTeracom is an Accredited Training Partner of the Telecommunications Certification Organization, authorized to administer exams for TCO certifications on the myTeracom Learning Management System and award TCO Certifications.
TCO Certification is proof of your knowledge of telecom, datacom and networking fundamentals, jargon, buzzwords, technologies and solutions.
It's backed up with a Certificate suitable for framing - plus a personalized Letter of Reference / Letter of Introduction detailing the knowledge your TCO Certification represents and inviting the recipient to contact Teracom for verification.
You may list Teracom Training Institute as a reference on your résumé if desired.
Each course has a course exam, consisting of ten multiple-choice questions chosen at random from a pool and shuffled in order. Passing the course exams proves your knowledge of these topics and results in your certification as a Certified Telecommunications Network Specialist.
Your Certificate and Letter of Reference / Letter of Introduction will be immediately available for download from your Dashboard in the myTeracom Learning Management System. You may also order a signed and sealed Certificate by airmail.
Choosing the "Unlimited Plan" at registration allows you to repeat courses and/or exams at no additional charge – which means guaranteed to pass if you're willing to learn.
Alternatively, if you like this discounted package of courses, but don't need the certification – or don't feel like writing exams – no problem! Take the Telecom, Datacom and Networking for Non‑Engineers course package, which includes the same courses as the CTNS certification package, without the certification exams.
One benefit of TCO certification is differentiating yourself from the rest of the crowd when applying for a job or angling for a promotion.
The knowledge you gain taking Teracom's Online Courses, confirmed with TCO Certification, is foundational knowledge in telecommunications, IP, networking and wireless: fundamental concepts, mainstream technologies, jargon, buzzwords, and the underlying ideas - and how it all fits together.
This type of knowledge and preparation makes you an ideal candidate to hire or promote to a task, as you will be able to build on your knowledge base to quickly get up to speed and work on a particular project - then have the versatility to work on subsequent projects.
TCO Certification will help demonstrate you have this skill... a desirable thought to have in your potential manager's mind.
Take advantage of these courses for individual learning, a team, or for an entire organization.
The scalable myTeracom Learning Management System can register and manage all of your people through their courses, lessons and exams, and generate management reports showing progress and scores with the click of a button.
For larger organizations, the courses and exams can also be licensed and deployed on an organization's internal LMS.
Teracom certification packages are an extremely cost-effective way of implementing consistent, comprehensive telecommunications and networking technology fundamentals training, ensuring that both existing resources and new hires are up to the same speed, with a common vocabulary, framework and knowledge base.
The course exams provide concrete measurements of competency in key knowledge areas. Management can view the progress and results of all team members and export the results to Excel with the click of a button.
These reports identify skills deficiencies and strengths, and provide tangible proof of return on investment and team readiness for reports to upper management.
What is the value of the CTNS certification? Click here to find out
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