Development #3: MPLS has replaced ATM

A closer look at the third item in our list of eight major recent developments and trends in telecom

Telecommunications technology is constantly changing and improving – seemingly faster and faster every year – and at Teracom, we keep our training courses up to date to reflect these changes.  In a previous post, we identified eight major developments and trends in telecommunications incorporated in our training.

In this post, we take a closer look at the third development:
MPLS has replaced ATM for traffic management, achieving  another long-held goal in the telecommunications business, called convergence or service integration.

A long-held goal in the telecommunications business has been to transport and deliver all types of communications on the same network and access circuit, and in an ideal world, with a single bill to the customer. This idea is sometimes called convergence, though service integration is a more accurate term.

It results in a large cost savings compared to different networks, access circuits and bills for each type of communications.
In days past, this was not the case.

A residence would have at least two entry cables: twisted pair for telephone and coax for television, and separate bills for each.

The situation was even worse and more expensive in the case of a medium or large organization.

At each location, a typical organization would have the requirement to communicate
• Telephone calls to/from the PSTN,
• Telephone calls to/from other locations of the organization,
• Data to/from other locations of the organization, and
• Data, video and possibly voice to/from the Internet.

In days past, the organization might have had four physical access circuits and services – along with four bills:
• ISDN PRI over T1 to a LEC for telephone calls to/from the PSTN,
• Tie lines or a voice VPN with a custom dialing plan from an IXC for telephone calls to/from other locations of the organization,
• Dedicated T1s from an IXC for data to/from other locations of the organization, and
• DSL, Cable or T1 access from an ISP for data, video and possibly voice to/from the Internet.

Not only did this mean four services and four access technologies and four bills for the customer, it also meant the carrier had to implement and support four network technologies… a very expensive situation.

MPLS for Service Integration

The solution to integrate all of this onto one access circuit and one network is twofold:
At the source,
• Format all types of traffic the same way, and
• Paste an identifier on the front of each piece of traffic, indicating what it is and where it goes.

Then all traffic can be carried interspersed on the same access circuit and in the same network, which results in a huge cost savings for both the customer and the carrier.

The identifier on the traffic is used to both route the traffic to the correct destination, and manage the traffic in the network, performing functions like load balancing, prioritization and restoration.

Starting in the 1980s, telephone companies and equipment manufacturers attempted to implement this with a technology called Asynchronous Transfer Mode (ATM). Literally billions of dollars were spent developing and deploying ATM from 1980 to 2000… but it failed and died, becoming too complex and too expensive, and not used for voice at the big telephone companies.

Multiprotocol Label Switching (MPLS) combined with IP has succeeded where ATM failed and is now universally implemented.

Of course, there is a lot of jargon to learn and many components to the “MPLS” story.

Here is a VERY brief explanation:
• All traffic is formatted into IP packets by the equipment that generates it, for example, a telephone or computer.
• Traffic is categorized into classes. A class of traffic goes from the same place to the same place and experiences the same transmission characteristics like delay and lost packets.
• A packet is identified as belonging to a particular class by pasting a number called a label on the front of the IP packet.
• The device that does the classification and labeling of packets is the ingress device, called a Label Edge Router in MPLS. It is normally Provider Equipment (PE), meaning owned and furnished by the service provider, located at the customer premise.
• Network equipment, called Label Switching Routers in MPLS, use the label number to route and in some cases prioritize the packet.
• Labels can be stacked, meaning one label pasted in front of another. This allows the network to manage similar kinds of traffic as a single entity in network control systems.

Returning to our example illustrated above, the four circuits illustrated at the top of the diagram can be replaced with one access circuit with three traffic classes (three labels). The physical access circuit could be 10 Mb/s to 10 Gb/s Optical Ethernet.

The three traffic classes / labels would be:
• A traffic class for telephone calls. This might be called a “SIP trunking service” by the marketing department. This class will carry VoIP phone calls to the carrier for communication to other locations of the organization, or for conversion to traditional telephony for phone calls to the public telephone network.
• A traffic class for data. This might be called a “VPN service” by the marketing department. This class carries file transfers, client-server database communications and the like securely to other locations of the organization.
• A traffic class for Internet traffic. This class carries anything in IP packets to the Internet.

All of this traffic is IP packets interspersed over the single access circuit.

At the other end of the access circuit, the carrier uses the label to route the traffic onward and possibly prioritize it to assure the appropriate service level.

The result is all of the organization’s traffic carried over a single access circuit, using a single technology.

This is one of the Holy Grails of the telecommunications business, called convergence or service integration, having significant advantages in cost and flexibility.

This is a concise description of a story that has many different facets.

In Teracom training, this discussion comes AFTER many other lessons explaining all of the underlying concepts, related technologies like PRI and SIP trunking and their jargon.

If you would like the whole story, it is currently included in the following training:

Course 101: Telecom, Datacom and Networking
for Non-Engineering Professionals

Certified Telecommunications Network Specialist (CTNS)
Online telecommunications certification courses

Telecom, Datacom and Networking for Non-Engineers textbook

and DVD-Video Courses V3 and V4.


Would you attend this course?

Would you attend this two-day course?
Inquiring minds want to know!

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Course 104
Network Fundamentals for Non‑Engineers

A two-day course for finance, strategy, management, software, customer support and other personnel providing a comprehensive overview and update on telecom network technologies.

Our goal is to bust the buzzwords, explain the jargon, technologies and standard practices in the telecom network business, and importantly, the underlying ideas and how it all fits together.

Complete with a detailed book for future reference, this course will fill in the gaps and provide you with the knowledge you need to eliminate frustration and be more accurate and productive.

This training is an investment that will be repaid many times over. Join us for this career-enhancing opportunity!

PDF Brochure Course 104 Network Fundamentals for Non-Engineers


Demystify Buzzwords And Jargon

One of the biggest challenges in telecommunications is all of the acronyms, abbreviations, jargon and buzzwords.

The list goes on and on: POTS, PSTN, loops, trunks, VoIP, SIP trunking, Hosted PBX, DSL, DS1, T1, PRI, ILEC, CLEC, POP, MAN, TDMA, CDMA, LAN, WAN, Ethernet, MAC address, MAC frame, IP packet, TCP/IP, OSI, Layer 2, Layer 3, VLAN, TDM, DWDM, FTTN, FTTH, FTTP, DHCP, NAT, MPLS, VPN, SLA, ISP, DNS …

Plus, there is a second-order problem: even if you were to figure out all of the current jargon and buzzwords, it’s certain that new ones will be invented next month!

It can be very frustrating sitting in meetings with these terms flying around and not understanding most of them… particularly when someone asks your opinion.

So the question is: how to get on top of all the jargon and buzzwords, knowing that there is going to be constant change?

Our answer: understand the fundamentals. Take the cover off the box and understand how it works. Once we do this, we discover that there are only a few main ideas in telecom technology, with incremental improvement in each area.

Taking this course and understanding the fundamental ideas puts you back in control, with the confidence to contribute effectively. Even if you don’t know the exact details of a product someone is discussing, you will still know what they are talking about.

Understand The Network Cloud

People like to draw a diagram of a network as a cloud with sticks poking into it, and refer to the network as “The Cloud”. This might be useful for drawing diagrams, but if you are using, planning, ordering, managing, troubleshooting, developing software for or otherwise involved with telecom circuits and services, understanding what’s inside is productivity- and career-enhancing knowledge.

In this course, you will learn how circuits and services are actually provided, giving you the knowledge to make meaningful comparisons and accurate decisions.

We’ll explore every different aspect of The Cloud:

  • The fundamental structure of the network: access, switching and transmission;
  • The companies that physically implement the network: ILECs, CLECs, IXCs, how and where they interconnect, and
  • The components of a service: access circuit technology, network service type and billing plan;
  • The equipment used: switches, routers, multiplexers, fiber and modems;
  • How users share the network: channels, packets and Service Levels.

Gain Vendor-Independent Knowledge You Can Build On

The knowledge you gain taking this training course is vendor-independent foundational knowledge in telecommunications.

You will be able to build on this proven knowledge base to quickly get up to speed for a particular project – then have the versatility to work on subsequent projects.

The cost of this training will be repaid in productivity gain many times over.

Based on Teracom’s proven instructor-led training courses developed and refined over twenty years providing training for organizations including AT&T, Verizon, Bell Canada, Intel, Microsoft, Cisco, Qualcomm, the CIA, NSA, IRS, FAA, US Army, Navy, Marines and Air Force and hundreds of others, Teracom online courses are top-notch, top-quality and right up to date with the topics and knowledge you need.

Teracom was awarded a US Government Federal Supply Schedule (GSA) contract for these training services… which involved an independent evaluation where we scored a 97% quality rating from our customers!

Join us today to make this invaluable addition to your knowledge and skills!


Course Outline

  1. Fundamentals of TelephonyIt all begins with the Public Switched Telephone Network and Plain Ordinary Telephone Service. We’ll establish with a model for the PSTN, explaining analog circuits, loops, trunks, remotes, circuit switching and other telephony buzzwords and jargon. We’ll understand how the network is organized into access, switching and transmission. We’ll cover Centrex and traditional PBX, then understand Voice over IP (VoIP) concepts and components, soft switches and SIP trunking.
  • History of Telecommunications
  • The Public Switched Telephone Network (PSTN)
  • Analog Circuits
  • What is Sound?
  • The Voiceband
  • Plain Ordinary Telephone Service (POTS)
  • DTMF Address Signaling
  • Signaling System 7 (SS7)
  • Network Architecture: Access, Switching, Transmission
  • Telephone Switches
  • Traditional PBX and Centrex
  • VoIP
  • SIP, Soft Switches, Hosted PBX and IP Centrex
  • SIP Trunking


2. Digital
With the fundamentals in place, we’ll cover digital. You will learn what is really meant by “digital”, how voice is digitized to 64 kb/s, and MP4 digital video. We’ll complete the story understanding how the resulting bits are communicated using binary pulses on copper and fiber.

  • Analog and Digital: What Do We Really Mean?
  • Continuous Signals, Discrete Signals
  • Voice Digitization (Analog Digital Conversion)
  • Voice Reconstruction (Digital → Analog Conversion)
  • Voice Digitization: 64kb/s G.711 Standard
  • Digital Video: H.264 / MPEG-4 Standard
  • Implementing Digital: Binary Pulses


3. The Telecommunications Industry, Competition and Interconnect
In this chapter, you will gain a solid understanding of the telecommunications business and how it is structured, including telephone companies, local and long-distance, and how these companies compete and interconnect. You will understand how each organization fits into the picture, including ILECs, IXCs, resellers, CLECs, collocations, regional rings, POPs and MANs.

  • US Domestic Telcos
  • AT&T and Verizon
  • PSTN Switching Center Hierarchy
  • 1984: LECs, IXCs and POPs – Last Mile: Switched Access from ILEC
  • Competitive Carrier – Last Mile: Dedicated Line from ILEC
  • Competitive Carrier – Last Mile CLEC: Collocation plus ILEC Dark Fiber
  • Competitive Carrier Network Model: Regional Rings, POPs and MANs


4. The Cloud
Next, we will demystify the Network Cloud. You will learn why people draw a picture of a cloud to represent a network, then most importantly, what is inside the cloud and understand what’s really going on. You will learn about the three basic kinds of network services available, the equipment used to implement each, and how services are actually provided… highly useful knowledge when planning, ordering, troubleshooting, auditing, or otherwise dealing with carrier services.

  • Anatomy of a Service
  • Inside the Network Cloud
  • Network Equipment: How and Where Each is Used
  • Summary: How Services Are Provided


5. “Data” Communications and Network Basics
We’ll begin the second day understanding what “convergence” is and how it was achieved by treating telephone calls and television like data communications. Then, we’ll get you up to speed on the concepts, jargon, buzzwords and technologies that were originally developed for datacom and now used for everything. You’ll learn the basic ITU model for data circuits, then plain English explanations of Ethernet, MAC frames and MAC addresses, IP packets and IP addresses, and how they relate.

  • Convergence: Treat Everything Like Data
  • Data Circuit Model
  • LANs
  • Wide Area Networks
  • Ethernet and 802 standards
  • Frames and MAC Addresses
  • LAN Switches
  • VLANs
  • Packets and IP Addresses
  • Packets vs. Frames


6. The OSI Layers and Protocol Stacks
There are so many functions that must be performed to interoperate systems, a structure is required to organize the functions so that separate issues can be treated separately. For this purpose, we’ll use the ISO Open Systems Interconnection 7-Layer Reference Model. You’ll learn what a layer is, the purpose of each layer, examples of protocols like TCP and IP used to implement layers, an overview of many different protocols and functions you’ve heard of, and understand how a protocol stack works for applications like web surfing and VoIP.

  • Protocols and Standards
  • ISO OSI Reference Model
  • OSI 7-Layer Model
  • Physical Layer: 802.3, DSL, DOCSIS
  • Data Link Layer: 802 MAC
  • Network Layer: IP and MPLS
  • Transport Layer: TCP and UDP
  • Session Layer: POP, SIP, HTTP
  • Presentation Layer: ASCII, Encryption, Codecs
  • Application Layer: SMTP, HTML, English …
  • Protocol Stack in Operation: Babushka Dolls
  • Standards Organizations


7. IP Networks, Routers and Addresses
This chapter is dedicated to IP. We begin with the simplest framework, a private network, to understand routing and bandwidth on demand. We’ll introduce the term Customer Edge router and examine the functions performed by a router. Then we will cover IPv4 addressing: IPv4 address classes, static vs. dynamic addresses and DHCP, public and private addresses and NAT, and IPv6, how IPv6 addresses are allocated and assigned, and types of IPv6 addresses.

  • Simplest IP Network Example: Routers Connected with Dedicated Lines
  • Routers and Customer Edge (CE)
  • IPv4 Address Classes
  • DHCP, Static and Dynamic Addresses
  • Public and Private IPv4 Addresses
  • Network Address Translation
  • IPv6 Address Allocation and Address Types


8. Transmission Systems
We’ll begin with the basics of fiber and wavelengths, then compare older channelized transmission systems like T1 and SONET to newer packet-based transmission systems based on IP and Optical Ethernet.

  • Fiber Optics and Fiber Cables
  • Wave-Division Multiplexing: CWDM and DWDM
  • Channelized Time Division Multiplexing (TDM)
  • DS0s and SONET Framing
  • Channelized Digital Hierarchy: Standard Legacy Transmission Speeds
  • Digital Carrier Systems: Legacy Transmission Technologies
  • Statistical Time Division Multiplexing
  • Overbooking and Bandwidth on Demand
  • IP Packets and Optical Ethernet


9. The Last Mile
To complete the transmission story, we’ll briefly explore how the “last mile” is connected: fiber to the premise, active and passive, and fiber to the neighborhood followed by DSL or cable modems on copper.

  • Fiber to the Premise: PONs and Active Ethernet
  • DSL
  • DSLAMs
  • Fiber to the Neighborhood (FTTN), DSL to the Premise
  • Broadband Carriers: FTTN & Broadband Coax to the Premise
  • DOCSIS and Cable Modem Standards


10. MPLS and Carrier Networks
IP packets will be used to carry everything, including phone calls and television. But IP in itself does not include any Quality of Service (QoS) mechanism, no way to prioritize or manage traffic. This is implemented with MPLS. In this chapter, you’ll learn the basics of carrier packet networks, identifying Provider Edge (PE), Customer Edge (CE), access and core, and the important concept of a Service Level Agreement. Then without bogging down on details, you’ll get a big-picture understanding of MPLS and how it is used to implement business customer services, differentiated services and Class of Service (CoS), service integration and traffic aggregation.

  • Carrier Packet Network Basics
  • Service Level Agreement
  • Provider Equipment at the Customer Premise
  • Virtual Circuit Technologies
  • MPLS
  • MPLS VPNs for Business Customers
  • MPLS and Diff-Serv to Support Classes of Service
  • MPLS for Service Integration
  • MPLS for Traffic Aggregation


11. The Internet
The Internet is a giant collection of interconnected IP networks called Autonomous Systems across which the public can communicate IP packets. In this chapter, we’ll understand what an ISP is and how they connect to others via transit and peering, and conclude by understanding telephone calls over the Internet and secure VPNs over the Internet.

  • A Network To Survive Nuclear War
  • The Inter-Net Protocol
  • Internet Service Providers
  • Internet Telephony & VSPs
  • Internet VPNs


12. Wrapping Up
The final chapter brings all of the concepts together with a top-down review. You’ll learn valuable insight into telecom project management and methodology, and review telecom, datacom and networking technologies, services and solutions. We’ll conclude with a peek at the future of telecommunications, where the telephone network and Internet become the same thing.

  • Technology Deployment Steps
  • Requirements Analysis
  • High-Level Design
  • Review: Circuits and Services
  • Access and Transmission Technology Roundup
  • Private Network
  • Carrier IP Services
  • The Future


Our goal is to explain the underlying concepts, providing you with a practical understanding of telecom technologies and services, without bogging down on details. You will gain a solid base of structured knowledge that can be applied to immediate projects and can be built on in the future… an investment in productivity that will be repaid many times over.

Six Reasons to Take This Course

Teracom’s courses have been taught to wide acclaim across North America since 1992 and are designed for professionals needing to fill in the gaps, build a solid base of knowledge and understand how it all fits together.

  1. Cut through the buzzwords, jargon and vendor hype to gain a structured understanding of telecommunications and networking, allowing you to make meaningful comparisons and informed decisions… knowledge skills you can put to use today and in the future.
  2. Get up to speed on the latest developments and trends. This course is totally up to date with SIP trunking, VoIP, Optical Ethernet, MPLS and more.
  3. Get a solid base of vendor-independent knowledge of technologies, service providers, standard practices and mainstream solutions that you can build on.
  4. Understand how it all fits together.
  5. Learn more with instructor-led training – the best kind of training you can get – where you can interact and ask questions with instructors consistently rated “excellent” on student evaluations.
  6. Obtain a course book with detailed notes that will be a valuable reference for years.

Develop a structure for understanding technologies and solutions, allowing you to make informed choices and meaningful comparisons — knowledge you can’t get on the job, reading trade magazines or talking to vendors.

Your Course Materials: An Invaluable Reference

Every course comes complete with a high-quality course book that’s been called the best on-the-job reference tool around. Written in plain English, this easy-to-use reference includes copies of all graphics PLUS extensive detailed text notes. Topics are organized in logical groups to give you easy reference after the seminar to the practical experience, theoretical background, and unbiased information on industry technologies, products and trends you’ll need. With numerous chapters covering all major topics, you’ll obtain an invaluable resource impossible to find anywhere else in one book.

Free Bonuses! Online Courses & CTNS Certification

As a free bonus, you get the full set of Teracom’s Online Courses. Not only are these an excellent way to take a second pass through various topics, the Online Courses include pictures of equipment and additional lessons beyond those in this course.

If you choose to write the optional exams, you can earn Telecommunications Certification Organization (TCO) Certified Telecommunications Network Specialist (CTNS) Certification, complete with Certificate suitable for framing and a personalized Letter of Reference for your résumé.

Certification is concrete proof of your knowledge. The included Unlimited Plan option allows you to repeat exams as needed until you pass… which means guaranteed to pass if you’re willing to learn!


Here’s What Seminar Attendees Like You Are Saying

Hundreds of people like you have benefited from Teracom’s core training. Many tell us this was their best course ever; filled gaps in their knowledge and tied everything together… knowledge they’ve been needing for years. Others on course their first week on the job remarked “what a wonderful way to get started in the business.”

Here’s a sampling of comments from Teracom alumni:

“Feedback from my team was TERRIFIC. It gave our entire technical Call Center a common foundation, and you seem to have crafted that perfect balance between technical depth, real-world applications, and lively delivery.  I couldn’t be happier with the results. The things my team learned from this training were applied in real-world situations almost immediately.”
– Rusty Walther, Vice President, Client Services, AboveNet Communications

“Excellent! I learned a lot – everyday terms, definitions, and acronyms. Seminar notebook very helpful. The instructor was the best I ever had – lots of knowledge and experience and stories were GREAT.”
– Serena Laursen, Microsoft

“The selection of material – the order of its presentation – the way it was presented… incredibly effective at presenting concepts and ideas – uses great analogies and stays on topic.”
– Susan Lennon, Nortel

“The seminar delivered exactly what was advertised, at a very high quality.
Truth in advertising!” – Gary Lundberg, Copper Mountain Networks

Whether you work for an organization that produces telecom, datacom or networking products or services; or you buy these products and services – or just have to get up to speed on what all the rest of them are talking about when they say “SIP trunking”, “Ethernet”, “MAC frame”, 4G, MPLS or VPN…

“Best course we have ever had onsite at 3Com”

“Perfect content; well organized, well paced, building block approach,
resulted in a very nice cathedral” – Jim George, Qualcomm

“Course was excellent! One of the best I have taken. Extremely well organized and presented. Seminar workbook is outstanding – a very valuable reference” – Kieran Delaney, Maritime Life

“I liked most the use of analogies to explain complex concepts. It delivered exactly what the brochure promoted. Gave me a thorough understanding so I feel more confident.”
– Judith Myers, Ameritech

“Excellent! Tied the individual pieces of knowledge together into a picture… was interactive and built up the knowledge layers properly.” – Jim Geiss, Qwest

“Filled in a lot of gaps in my knowledge of networking… able to deliver the knowledge effectively and entertainingly. Excellent seminar”- Kirk Kroeker, IEEE Computer Society

“Great information that I will be able to use at work. Very easy to understand all the information especially the IP networking part. I wouldn’t change a thing”
– Orlando Jasso, AboveNet Communications.

“Layman’s terms with humor was very relaxing – helped me concentrate… understanding is now CLEAR … the manual will be very helpful” – Linda Côté, Bell Canada

“Best instructor I have had on a course – excellent explainer in layman terms, not techie terms”
– Susan Coleman, Bell Sygma

“Best course materials ever; the full text descriptions are invaluable.
Course filled in so many gaps for me. Bravo!” – Ross Brooks, Vertek

“Outstanding! The best I’ve encountered, and I’ve attended many seminars.”
– Bob Gibbons, WMX Technologies


Private Onsite Courses

Since 1992, we have provided high-quality on-site training in telecommunications for non-engineering professionals at AT&T, Verizon, Bell Canada, TELUS, Qualcomm, 3Com, Cisco, Intel, Alcatel, Nortel, Teleglobe, the NSA, Defense Information Systems Agency, US Coast Guard, US Air Force, Office of Naval Intelligence, MindSpring, APEX Telecom, Equifax, Transamerica Insurance, The Hartford, American Broadband, Cap Gemini, ComSec Establishment, MicroCell Telecom, TDS Telecom, Kyocera, Winstar, Western Wireless, US Cellular, Ericsson/Hewlett-Packard, Entergy, Intelsat, RangeTel, Alltel, Vertek, DSCI, Cox Cable, Florida Power and Light, Frontier Communications, Western Iowa Telephone, Genuity, LG Electronics, Panasonic, SouthEast Telephone, State of Nebraska, State of Montana, Tektronix, Bermuda Telecom, UTS and the Universal Service Administrative Company… to name a few. Plus, we have a GSA contract with pre-approved government pricing.

Onsite training has special advantages:

  • Your personnel will be up to a common speed with a solid knowledge base.
  • We’ll fill in the gaps and put in place productivity-enhancing structured understanding of telecom and networking fundamentals, wireless, TCP/IP, MPLS, VoIP… to meet your requirements..
  • The seminar will be a strong team-building exercise.
  • Significant reductions in training costs are often achieved.
  • Each student receives a detailed workbook / textbook that will be a valuable reference for years to come.
  • Pre- and post-training testing is available, including team results on a spreadsheet

We have built a solid reputation for delivering high-quality private team-training programs that are a resounding success. We’d like to do the same for you! Please contact us at 1-877-412-2700 for more information.


About the Author

Eric Coll
Eric Coll, M. Eng.

Eric Coll is an international expert in telecommunications, data communications and networking and has been actively involved in the industry since 1983. He holds Bachelor of Engineering and Master of Engineering (Electrical) degrees.

Mr. Coll has taught telecommunications technology training seminars to wide acclaim across North America since 1992, and has broad experience working as an engineer in the telecommunications industry.  He has worked for Nortel’s R&D labs as a design engineer on projects including digital voice and data communications research and digital telecom network equipment design, and on satellite radar systems, consulting on Wide Area Network design, and many other projects in capacities ranging from detailed design and implementation to systems engineering, project leader and consultant.

In addition to being founder and Director of Teracom Training Institute, Mr. Coll provides consulting to the telecommunications industry, specializing in telecommunications technology R&D and as a Subject Matter Expert in tax matters.