Carriers and Interconnect To allow communications between customers of different carriers, the carriers must implement physical connections between their networks. In this module, you’ll learn how the Internet is actually implemented, with peering and transit agreements at Internet Exchange buildings. You will also learn about POPs in toll centers: how and where local exchange service providers: ILEC, mobile providers and CATV connect together and to other carriers for phone calls with a PSTN phone number; and SS7 to set up the calls. We’ll finish by understanding where a CLEC fits into the picture with equipment collocated in wire centers. Telecom Module 11 Detailed Outline 11 Carriers and Interconnect 11.1 IX: Internet Exchange - Interconnect for Internet Traffic ...... 11.1.1 Fiber to an AS ...... 11.1.2 Transit ...... 11.1.3 Peering 11.2 Telephone Network Architecture ...... 11.2.1 Access Network ...... 11.2.2 Switching Network ...... 11.2.3 Transmission Network 11.3 PSTN Switching Centers, COs and Toll Centers ...... 11.3.1 Class 5: Central Office ...... 11.3.2 Wire Center ...... 11.3.3 Local Calls ...... 11.3.4 Class 4: Toll Center ...... 11.3.5 Class 1, 2 and 3 Switching Centers ...... 11.3.6 High Usage Trunks 11.4 Implementing Competition: LECs, POPs and IXCs ...... 11.4.1 LECs, ILECs and CLECs ...... 11.4.2 Inter-Exchange Carriers: IXCs ...... 11.4.3 POP: Point of Presence ...... 11.4.4 Switched Access ...... 11.4.5 Equal Access and PIC Codes 11.5 Wireless and CATV Local Exchange Carriers 11.6 CLEC: Collocations and Dark Fiber ...... 11.6.1 Unbundling ...... 11.6.2 Dark Fiber and Dry Copper ...... 11.6.3 Competitive Local Exchange Carrier (CLEC) ...... 11.6.4 Collocations ...... 11.6.5 Advantages ...... 11.6.6 Disadvantages ...... 11.6.7 Application 11.7 SS7 ...... 11.7.1 Carrier Interconnect ...... 11.7.2 Call Setup ...... 11.7.3 Out-Of-Band Signaling ...... 11.7.4 Service Control Points and Service Switching Points ...... 11.7.5 Advanced Intelligent Network (AIN) ...... 11.7.6 Switch-Based Call Routing ...... 11.7.7 SS7 In Practice ...... 11.7.8 Residential Service Application Example ...... 11.7.9 Business Service Application Example
Mobility With a good foundation in place, we’ll cover mobile communications from A to Z: cellular principles, digital voice, phone calls to the PSTN and mobile Internet. This is where the money is! Wireless Module 2 Detailed Outline 2 Mobility 2.1 Mobile Network Components and Operation ...... 2.1.1 Mobile Network and Mobility ...... 2.1.2 Handset, SIM Card and IMSI ...... 2.1.3 Airlink, Base Station, Towers and Cells ...... 2.1.4 Mobile Telephone Switching Office ...... 2.1.5 Backhaul and Network Connections ...... 2.1.6 Incoming Call and Paging ...... 2.1.7 Mobility and Handoffs 2.2 Cellular Principles ...... 2.2.1 Coverage, Capacity and Mobility Requirements ...... 2.2.2 First Generation ...... 2.2.3 Cellular Design to Meet the Coverage Objective ...... 2.2.4 Frequency Re-use ...... 2.2.5 Handoffs 2.3 1G: Analog Frequency-Division Multiple Access ...... 2.3.1 AMPS, NMT and TACS ...... 2.3.2 Frequency-Division Multiplexing ...... 2.3.3 Frequency Re-Use ...... 2.3.4 Analog FM ...... 2.3.5 Difficulties ...... 2.3.6 Eavesdropping ...... 2.3.7 Modem Disconnect During Handoff ...... 2.3.8 Low Capacity 2.4 PSTN Calls Using the Native Phone App: "Voice Minutes" ...... 2.4.1 Voice Communication End to End ...... 2.4.2 Coding 2.5 Mobile Internet: "Data Plan" ...... 2.5.1 “Data” is Internet Traffic ...... 2.5.2 Using the Built-in Modem ...... 2.5.3 Tethered Modem ...... 2.5.4 Wi-Fi and Bluetooth Links ...... 2.5.5 Smartphones ...... 2.5.6 Data Plans ...... 2.5.7 Converged Communications + Converged Device Achieved 2.6 Mobile Network Operators, MVNOs & Roaming ...... 2.6.1 Mobile Network Operator ...... 2.6.2 Mobile Virtual Network Operator ...... 2.6.3 Roaming
LTE and 5G In the third Wireless module, we cover the 4G and 5G technology, understanding how both use OFDM for spectrum-sharing and OFDMA for simultaneous communication with many users. Wireless Module 3 Detailed Outline 3 LTE and 5G 3.1 4G LTE: Mobile Broadband ...... 3.1.1 Introduction ...... 3.1.2 LTE for the UTRAN ...... 3.1.3 Modems, Modulation, and How OFDM Moves 6-Bit Numbers Simultaneously to Different People on the Same Carrier ...... 3.1.4 Modulation ...... 3.1.5 Communicating Six Bits: Sending One of 64 QAM Signals ...... 3.1.6 Baud Rate Equal to Subcarrier Spacing ...... 3.1.7 LTE Specification and OFDMA ...... 3.1.8 3GPP Releases ...... 3.1.9 The Eventual Pivot To 5G Across the Spectrum 3.2 Dynamic Assignment of Subcarriers ...... 3.2.1 1G vs. 4G and 5G 3.3 5G New Radio: Enhanced Mobile Broadband, IoT Communications ...... 3.3.1 Introduction ...... 3.3.2 3GPP Release 15 ...... 3.3.3 Immediate Impact Of 5G: More Bits Per Second ...... 3.3.4 New Spectrum ...... 3.3.5 Millimeter-wave ...... 3.3.6 5G Design Goals and Use Cases ...... 3.3.7 Enhanced Mobile Broadband ...... 3.3.8 Massive Machine-type Communication ...... 3.3.9 Ultra-Reliable, Low-Latency Communications 3.4 Spectrum-Sharing Roundup: FDMA, TDMA, CDMA, OFDMA ...... 3.4.1 FDMA ...... 3.4.2 TDMA ...... 3.4.3 CDMA ...... 3.4.4 OFDM and OFDMA
Digital Media: Voice, Video, Images, Quantities and Text The converged network carries all media: voice, video, text and images in packets. An essential first step is digitizing the media, representing it using 1s and 0s, to be carried in said packets. We’ll first understand analog vs. digital, how voice is digitized and reconstructed, the G.711 64 kb/s and AMR codec standards. The same principles apply to images and video in formats like jpg and mp4 video. We’ll make sure you are up to speed on binary and hexadecimal for quantities, and finish with ASCII and unicode for coding keystrokes and emojis. Telecom Module 6 Detailed Outline 6 Digital Media: Voice, Video, Images, Quantities, Text 6.1 Analog and Digital: What do we really mean? ..... 6.1.1 Analog Signal ..... 6.1.2 Analog Circuit ..... 6.1.3 Digital Signal ..... 6.1.4 Digital Circuit ..... 6.1.5 Bandwidth 6.2 Continuous vsDiscrete Signals ..... 6.2.1 Continuous Signals ..... 6.2.2 Discrete Signals 6.3 Voice Digitization (Analog-Digital Conversion) ..... 6.3.1 Quantization ..... 6.3.2 Sampling ..... 6.3.3 Coding 6.4 Voice Reconstruction (Digital - Analog Conversion) ..... 6.4.1 Reconstruction ..... 6.4.2 Quantization Error ..... 6.4.3 Aliasing Error 6.5 Voice Digitization: 64 kb/s G.711 Standard ..... 6.5.1 256 Quantization Levels ..... 6.5.2 8,000 Samples per Second ..... 6.5.3 8-bit Coding ..... 6.5.4 64 kb/s G.711 Codec Standard ..... 6.5.5 64 kb/s DS0 Channels ..... 6.5.6 64 kb/s Packetized Voice ..... 6.5.7 AMR Codec for Cellular ..... 6.5.8 mu-law and a-law 6.6 Digital Video, H.264 and MPEG-4 ..... 6.6.1 Digital Video Cameras ..... 6.6.2 Factors Affecting Video Quality ..... 6.6.3 Definition vsResolution ..... 6.6.4 Standard Definition, Interlaced and 480i ..... 6.6.5 High Definition, Progressive and 720p ..... 6.6.6 Full HD 1080 and 2K ..... 6.6.7 Ultra HD, 4K, 8K, … 4M ..... 6.6.8 Compression ..... 6.6.9 MPEG ..... 6.6.10 MPEG-4 and H.264 6.7 Digital Images: JPEGs and GIFs ..... 6.7.1 Lossless Compression: PNG ..... 6.7.2 Lossy Compression: JPEG and GIF 6.8 Digital Images in Email: MIME ..... 6.8.1 UUENCODE, Quoted-Printable and Base-64 Encoding 6.9 Digital Quantities: Number Systems 6.10 Digital Quantities: Binary 6.11 Digital Quantities: Hexadecimal ..... 6.11.1 Common Use for Hexadecimal 6.12 Digital Text ..... 6.12.1 ASCII ..... 6.12.2 Unicode
The Internet, Cloud Computing and Data Centers The Internet, which started out as a way to send text email messages, is now worldwide converged broadband communications. In this module, we’ll understand what exactly an Internet Service Provider does, and how they get packets delivered world-wide. We’ll review web clients, browsers and apps, web servers, then understand the huge business of web services, cloud computing and data centers. You'll also learn about all the different types of VPN, and how SD-WAN services are Internet VPNs. We'll finish with a discussion of Net Neutrality. Telecom Module 4 Detailed Outline 4 The Internet and Cloud Computing 4.1 A Network to Survive Nuclear War ..... 4.1.1 Connectionless Network Service ..... 4.1.2 Al Gore Invents the Internet ..... 4.1.3 Who Pays for the Internet? ..... 4.1.4 Primitive Beginnings 4.2 The Inter-Net Protocol ..... 4.2.1 Gateways ..... 4.2.2 IP: Common Packet Format and Address Scheme ..... 4.2.3 Connectionless, Unreliable Network Service ..... 4.2.4 TCP and UDP ..... 4.2.5 Routing Protocols 4.3 Internet Service Providers (ISPs) ..... 4.3.1 Internet Access Providers ..... 4.3.2 The Internet is a Business ..... 4.3.3 Interconnect, Peering and Transit ..... 4.3.4 Resellers 4.4 Domain Name System ..... 4.4.1 DNS Servers ..... 4.4.2 Domain Zone Files ..... 4.4.3 SIP Records in DNS 4.5 Web Clients ..... 4.5.1 Browsers ..... 4.5.2 Apps ..... 4.5.3 IoT Apps 4.6 Web Servers ..... 4.6.1 HTTP ..... 4.6.2 HTTPS ..... 4.6.3 HTML ..... 4.6.4 HREFs and URLs 4.7 Web Services and Cloud Computing ..... 4.7.1 Web Server and Back End ..... 4.7.2 Doing it Yourself & Dynamic DNS ..... 4.7.3 Web Hosting ..... 4.7.4 Virtualization and Cloud Computing ..... 4.7.5 Amazon AWS, Microsoft Azure 4.8 Data Centers ..... 4.8.1 Commercial Multi-Tenant Data Centers ..... 4.8.2 Collocation ..... 4.8.3 Heat and Electricity ..... 4.8.4 Connections to Internet Exchanges 4.9 Internet VPNs ..... 4.9.1 Tunnels Implemented with Encryption ..... 4.9.2 IP VPN vsMPLS VPN ..... 4.9.3 Country-Spoofing VPNs ..... 4.9.4 Anonymizer VPNs 4.10 SD-WAN ..... 4.10.1 Pairwise Internet VPN Tunnels ..... 4.10.2 No Guarantees ..... 4.10.3 Bandwidth Management ..... 4.10.4 Implementation and Standards ..... 4.10.5 Service Bundling 4.11 Net Neutrality ..... 4.11.1 No Corporate or Government Interference ..... 4.11.2 Relayed Without Regard for Content, Senders, or Receivers ..... 4.11.3 Many Different Meanings ..... 4.11.4 Criminal Activities ..... 4.11.5 Transparency ..... 4.11.6 Devil in the Details ..... 4.11.7 No Meters ..... 4.11.8 Zero-Rating
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 way to prioritize or manage IP packets, to guarantee call quality or video quality. In the core of a carrier’s network, MPLS is used to implement those functions. In this module, you’ll learn the basics of carrier networks and the important concept of a Service Level Agreement. Then you’ll gain a practical understanding of how MPLS works and how it is used by carriers to implement VPNs, different Classes of Service, service integration and traffic aggregation. Telecom Module 15 Detailed Outline 15 MPLS and Carrier Networks 15.1 Introduction ...... 15.1.1 Overbooking ...... 15.1.2 Congestion, Contention and Packet Loss ...... 15.1.3 Class of Service (CoS) 15.2 Carrier Packet Network Basics ...... 15.2.1 Provider Edge (PE) and Customer Edge (CE) ...... 15.2.2 Access ...... 15.2.3 Advantages of Packet Networks 15.3 Service Level Agreements ...... 15.3.1 Traffic Profile ...... 15.3.2 Contract ...... 15.3.3 Business Decisions ...... 15.3.4 Enforcement: Out of Profile Traffic ...... 15.3.5 Abusive Applications 15.4 Provider Equipment at the Customer Premise 15.5 Virtual Circuit Technologies ...... 15.5.1 IP Routing vsCentralized Control ...... 15.5.2 Traffic Classes ...... 15.5.3 Virtual Circuits ...... 15.5.4 SVCs and PVCs ...... 15.5.5 Ingress Device: Packet Classification ...... 15.5.6 Forwarding Based on Class Number ...... 15.5.7 Differentiated Services 15.6 MPLS ...... 15.6.1 MPLS vsTCP ...... 15.6.2 Forwarding Equivalence Class ...... 15.6.3 Labels and Label Stacking ...... 15.6.4 Label-Switched Path ...... 15.6.5 IP User-Network Interface ...... 15.6.6 Label Edge Routers ...... 15.6.7 Label-Switching Router Operation 15.7 MPLS VPN Service for Business Customers ...... 15.7.1 Private Network Service ...... 15.7.2 Virtual Private Network (VPN) ...... 15.7.3 Internet VPNs ...... 15.7.4 MPLS VPN 15.8 MPLS and Diff-Serv to Support Class of Service ...... 15.8.1 DS Codepoints ...... 15.8.2 Assured Forwarding and Expedited Forwarding 15.9 MPLS for Integrated Access ...... 15.9.1 SIP Trunking, VPN and Internet on One Access 15.10 MPLS for Traffic Aggregation ...... 15.10.1 Label Stacking 15.11 M is for Multiprotocol: Virtual Private LAN Service (VPLS)
Fundamentals of Voice over IP A complete introduction to everything Voice over IP: you'll learn the fundamental ideas and principles of a VoIP telephone system, the jargon and buzzwords, and how it all works together. You’ll learn: • How voice is carried in packets end-to-end, • VoIP phones, • Call Managers and Softswitches, • Cloud Services, • SIP and SIP Trunking, • VoIP on LANs and WANs, and • The Future. VoIP Module 1 Detailed Outline 1. Fundamentals of Voice over IP 1.1 Introduction 1.2 VoIP Phones ...... 1.2.1 Computers That Look Like Telephones ...... 1.2.2 VoIP Phone Functions ...... 1.2.3 Quality of Service and Differentiated Services ...... 1.2.4 Computer as the Terminal ...... 1.2.5 VoIP over Cellular ...... 1.2.6 Summary 1.3 Voice in IP Packets ...... 1.3.1 Voice in IP Packets End-to-End ...... 1.3.2 Missing or Delayed Packets 1.4 SIP and Soft Switches / SIP Servers / Call Managers ...... 1.4.1 Introduction ...... 1.4.2 “Hard” Switch ...... 1.4.3 Soft Switch ...... 1.4.4 Functions of a Soft Switch ...... 1.4.5 Soft Switch Terminology 1.5 Media Servers ...... 1.5.1 Introduction ...... 1.5.2 Integrated Messaging Server ...... 1.5.3 Video Server ...... 1.5.4 Other Types of Media Servers 1.6 Gateways ...... 1.6.1 Introduction ...... 1.6.2 Media Conversion ...... 1.6.3 Signaling Conversion 1.7 VoIP Over LANs and WANs ...... 1.7.1 Introduction ...... 1.7.2 LANs ...... 1.7.3 WANs 1.8 Key VoIP Standards ...... 1.8.1 Introduction ...... 1.8.2 IETF Standards ...... 1.8.3 ITU-T Standards ...... 1.8.4 IEEE LAN Standards ...... 1.8.5 TIA Cable Standards 1.9 Broadband IP Dial Tone ...... 1.9.1 The IP-PSTN ...... 1.9.2 IP Dial Tone ...... 1.9.3 The Internet and the Telephone Network Become One ...... 1.9.4 Value-Added Services
The PSTN and Broadband on Copper Before wireless and fiber, two copper wires were used for the physical access circuit for telephone and cable TV service in suburbs and cities. Today, these wires are also used to deliver broadband. In this module, we’ll understand how DSL broadband service runs on twisted pairs put in place for analog POTS telephone service; how cable modems move broadband on coaxial cable; and how both are delivered as fiber to the neighborhood then copper to the premise. To finish up, we’ll review digital on copper wires: LAN cables and T1s. Telecom Module 9 Detailed Outline 9 The PSTN and Broadband on Copper 9.1 The Public Switched Telephone Network ..... 9.1.1 Basic Model of the PSTN ..... 9.1.2 Loops ..... 9.1.3 Trunks and Circuit Switching ..... 9.1.4 Remotes ..... 9.1.5 DSL and DSLAMs in Brownfields ..... 9.1.6 Greenfields: PONs on Fiber to the Premise ..... 9.1.7 Active Ethernet to the Premise 9.2 Analog ..... 9.2.1 Analog Signals ..... 9.2.2 Analog Circuits 9.3 Capacity Restrictions ..... 9.3.1 What is Speech? ..... 9.3.2 Do Trees Falling in the Forest Make a Sound? ..... 9.3.3 The Voiceband ..... 9.3.4 Bandwidth ..... 9.3.5 Why Does the Voiceband Stop at 3300 Hz? ..... 9.3.6 Problems With Voiceband Restrictions 9.4 Problems with Analog Transmission ..... 9.4.1 Attenuation and Amplifiers ..... 9.4.2 Electro-Magnetic Interference ..... 9.4.3 Crosstalk ..... 9.4.4 Impulse Noise 9.5 Plain Ordinary Telephone Service (POTS) ..... 9.5.1 Tip and Ring ..... 9.5.2 Twisted Pair ..... 9.5.3 Line Card ..... 9.5.4 Microphone and Speaker ..... 9.5.5 Balanced Signaling ..... 9.5.6 Two-Way Simultaneous ..... 9.5.7 Hybrid Transformer ..... 9.5.8 Battery ..... 9.5.9 Lightning Protection ..... 9.5.10 Supervision ..... 9.5.11 Call Progress Tones 9.6 Network Addresses: Telephone Numbers ..... 9.6.1 Dialing Plan ..... 9.6.2 Address Signaling ..... 9.6.3 Pulse Dialing ..... 9.6.4 DTMF: “Touch Tone” ..... 9.6.5 In-Band Signaling ..... 9.6.6 “Hidden” Buttons ..... 9.6.7 Caller ID 9.7 Digital Subscriber Line (DSL) ..... 9.7.1 DSL: Modems Above the Voiceband ..... 9.7.2 ADSL, SDSL and XDSL 9.8 DSLAMs ..... 9.8.1 Coexistence with POTS 9.9 Fiber to the Neighborhood(FTTN), DSL to the Premise ..... 9.9.1 Loop Length ..... 9.9.2 Remote DSLAMs, OPI and SAC Boxes 9.10 DSL Standards ..... 9.10.1 ADSL2+ ..... 9.10.2 VDSL2 ..... 9.10.3 VDSL2 Frequency Bands and Profiles ..... 9.10.4 Pair Bonding ..... 9.10.5 Vectoring 9.11 Broadband Carriers: FTTN & Broadband Coax to the Premise ..... 9.11.1 Hybrid Fiber-Coax Network ..... 9.11.2 Frequency Channels ..... 9.11.3 Fiber Serving Area ..... 9.11.4 Television Converters ..... 9.11.5 Modems on CATV Channels ..... 9.11.6 Two-Way Communications Over a Shared Cable 9.12 DOCSIS and Cable Modem Standards ..... 9.12.1 DOCSIS 1: Contention-Based Channel Sharing ..... 9.12.2 DOCSIS 2: Reserved Time Slots on Channels ..... 9.12.3 DOCSIS 3: CDMA on Channels ..... 9.12.4 DOCSIS 3.1: OFDM ..... 9.12.5 Wider Channels 9.13 T1 and E1 ..... 9.13.1 Time-Division Multiplexers ..... 9.13.2 DS1 Frames ..... 9.13.3 CSUs and Repeaters ..... 9.13.4 Synchronization ..... 9.13.5 Applications for T1 ..... 9.13.6 E1 Outside North America ..... 9.13.7 TDM on Fiber 9.14 TIA-568 LAN Cable Categories ..... 9.14.1 Category 1 through 5 ..... 9.14.2 TIA-568A vsTIA-568B ..... 9.14.3 Maximum Cable Length and Cabling Architecture ..... 9.14.4 Difference Between Categories ..... 9.14.5 Which Category to Use
Eight in One! Telecom, Datacom and Networking for Non-Engineers is a subset of the 550-page Telecom 101, stripped down to the core: eight chapters corresponding to the eight CTNS courses, key chapters delivering the core telecommunications and telecom network knowledge needed by anyone serious in telecom today – in plain English: 1 Introduction to Broadband Converged IP Telecom 2 Wireless Telecommunications 3 Fundamentals of Voice over IP 4 The PSTN 5 OSI Layers and Protocol Stacks 6 LANs, VLANs, Wireless and Optical Ethernet 7 IP Addresses, Packets and Routers 8 MPLS and Carrier Networks Based on the world-renowned TCO CTNS certification courses, training developed, refined and tuned over many years, the selection of material, its order and emphasis is proven and field-tested to bring you the knowledge you need. Our approach can be summed up with a simple philosophy: Start at the beginning. Progress in a logical order. Build one concept on top of another. Finish at the end. Avoid jargon. Bust the buzzwords, demystify jargon, and cut through doubletalk. Fill in the gaps, build a solid base of knowledge, put a structure in place, and show how everything fits together... knowledge and understanding that lasts a lifetime. Understanding what everything does and how it all works together allows you to be more accurate, eliminates frustration with buzzwords, being left out of discussions, giving you confidence to make meaningful contributions. You have the added advantage of knowing what someone is talking about, even if you’re not familiar with the exact details of the variation they’re discussing. Telecom, Datacom and Networking for Non-Engineers is ideal for anyone needing a book covering the essential core knowledge in telecommunications in plain English. In one book, you get consistency, completeness and unbeatable value: a wealth of clear, concise, organized knowledge, impossible to find in one place anywhere else. Telecom, Datacom and Networking for Non-Engineers, has two parts; first, a deep dive into Telecom: Introduction to Broadband Converged IP Telecom Wireless Telecommunications Fundamentals of Voice over IP and The PSTN then a deep dive into Datacom and Networking: OSI Layers and Protocol Stacks LANs, VLANs, Wireless and Optical Ethernet IP Addresses, Packets and Routers and MPLS and Carrier Networks Let’s get started!
SIP Trunking & Carrier Connections This module is all about connecting to carriers to communicate VoIP phone calls, both carrier-to-carrier connections and business-to-carrier SIP trunking. You'll learn how competitive carriers terminate VoIP phone calls on Local Exchange Carriers using the switched access tariff and tandem access trunks. We'll understand why this will be a native VoIP connection in the future, and the role of Session Border Controllers. Then we'll understand how a business system can connect its locations and to the PSTN using SIP Trunking services, and the advantage over the legacy ISDN PRI PBX trunks. VoIP Module 5 Detailed Outline 5. SIP Trunking and Carrier Connections 5.1 Carrier-to-Carrier Connection via Tandem Access Trunks ...... 5.1.1 Internet VSP to LEC ...... 5.1.2 Generalized Carrier-Carrier Example ...... 5.1.3 Competitive Long-Distance 5.2 Carrier-to-Carrier VoIP Interconnection ...... 5.2.1 Native VoIP Interconnect ...... 5.2.2 Issues to Resolve 5.3 Session Border Controllers ...... 5.3.1 MPLS Core ...... 5.3.2 SIP Trunking ...... 5.3.3 Security, Lawful Intercept and Call Routing ...... 5.3.4 Spam Filtering 5.4 PBX Trunks and Gateways ...... 5.4.1 Business Phone System – PSTN Connectivity ...... 5.4.2 Legacy PBXs and PBX Trunks ...... 5.4.3 Replacing the PBX with a Softswitch ...... 5.4.4 Using a Gateway ...... 5.4.5 Intelligent Gateway Invisible to the Softswitch 5.5 Megaco: Softswitch Controlling the Gateway ...... 5.5.1 Non-Intelligent Gateway ...... 5.5.2 Softswitch Tells The Gateway What to Do ...... 5.5.3 Media Gateway Control Protocol (Megaco) 5.6 SIP Trunking ...... 5.6.1 PBX Trunk Replacement ...... 5.6.2 Advantages ...... 5.6.3 Challenges
VoIP 101 is designed for the non-engineering professional needing an overview and update, and for those new to the business needing to get up to speed quickly. VoIP 101 covers all major topics in Voice over IP – in plain English. From fundamentals to softswitches and SIP trunking, we’ll explain the jargon and the technologies, and more importantly, the underlying ideas. Based on training courses developed, refined and tuned over many years, the selection of material, its order and emphasis in VoIP 101 is proven and field-tested to bring you the knowledge of Voice over IP you need. Understanding what everything does and how it all works together allows you to be more accurate, eliminates frustration with buzzwords, and gives you confidence to make meaningful contributions. You have the added advantage of knowing what someone is talking about, even if you’re not familiar with the exact details of the variation they’re discussing. Don't be the one person in the room who isn't up to speed! Your employer (or prospective employer) will be interested to hear you have this solid foundation of knowledge that project- and product-specific knowledge can be built on, getting you up to speed quickly… then having the versatility to subsequently work on different projects. VoIP 101 has six chapters covering all aspects of Voice over IP, including all the different ways VoIP is implemented, how calls are set up with softswitches and SIP, how voice is packetized, the factors affecting sound quality, connecting to carriers and SIP trunking, and network quality with MPLS, Service Level Agreements and Class of Service: 1 Fundamentals of Voice over IP A complete introduction to everything Voice over IP. You'll learn the fundamental ideas and principles of a VoIP telephone system, the jargon and buzzwords, and how it all works together. 2 VoIP Architectures and Implementation Choices Next is a comprehensive overview of the many flavors of VoIP, comparing and contrasting the various implementation and architecture choices. 3 Softswitches, SIP, Call Setup and SIP Trunking This chapter is all about SIP, and how it is used to set up phone calls: what SIP is, how it works, jargon like proxy server and location server, how SIP fits in with softswitches and call managers, and trace the establishment of a VoIP phone call using SIP and DNS, step by step. 4 Voice Packetization, Codecs and Voice Quality The "nuts and bolts" of Voice over IP: how the voice is digitized and coded, time stamps applied with the RTP protocol, and how the result is carried in UDP, IP packets and MAC frames. 5 SIP Trunking & Carrier Connections This chapter is all about connecting to carriers to communicate VoIP phone calls, both carrier-to-carrier connections and business-to-carrier SIP trunking. 6 IP Network Quality: CoS, QoS, MPLS and SLAs The last chapter in VoIP 101 focuses on the network service provided by carriers to move VoIP packets, and how network traffic is identified, managed and prioritized, resulting in Class of Service offerings to meet Service Level Agreements. VoIP 101 is intended to be read sequentially, building ideas on top of ideas. The detailed Table of Contents makes it also useful as a day-to-day reference handbook. Our goal is to explain the big picture, the jargon and buzzwords, and put in place a very solid base of VoIP knowledge spanning fundamentals to the latest technologies and how they are deployed – in plain English. Let’s get started!
Wireless Telecommunications In this comprehensive module, you will learn all about wireless transmission, beginning with the radio spectrum. We’ll identify the components and basic principles of operation of a mobile network. You’ll understand the requirements for coverage, capacity and mobility, and why cellular radio systems are used. You’ll learn how mobile to PSTN phone calls are connected, how mobile Internet works, along with roaming and virtual network operators. You’ll learn about OFDMA, 4G LTE and 5G for mobile, and for 3.5 GHz fixed wireless home internet. We’ll cover WiFi and the latest Wi-Fi 6 802.11ax standard, and finish with satellite communications and Starlink. Telecom Module 7 Detailed Outline 7 Wireless Telecommunications 7.1 Radio 7.2 Spectrum ..... 7.2.1 The Need for Regulation ..... 7.2.2 Radio Spectrum ..... 7.2.3 Capacity vsPerformance Tradeoff ..... 7.2.4 Two-Way Radio: FDD or TDD ..... 7.2.5 Frequency Bands ..... 7.2.6 600 MHz Band ..... 7.2.7 700 MHz Band ..... 7.2.8 800, 900, 1800 and 1900 MHz bands ..... 7.2.9 2.4 GHz and 5 GHz Unlicensed Bands ..... 7.2.10 2.5 GHz Band ..... 7.2.11 3.5 GHz Band ..... 7.2.12 3.7 GHz C-Band 5G ..... 7.2.13 Millimeter-Wave Bands 7.3 Mobile Network Components and Operation ..... 7.3.1 0G: The Mobile Phone System ..... 7.3.2 Mobility ..... 7.3.3 Base Station, Cell, Airlink, Handset and SIM ..... 7.3.4 Mobile Switch ..... 7.3.5 Backhaul ..... 7.3.6 Registration and Paging ..... 7.3.7 Handoff 7.4 Cellular Principles ..... 7.4.1 AMPS: The Advanced Mobile Phone System ..... 7.4.2 Cells ..... 7.4.3 Frequency Re-Use ..... 7.4.4 1G: Analog Frequency-Division Multiple Access ..... 7.4.7 Sectorization 7.5 Second Generation: Digital ..... 7.5.1 PCS and GSM 7.6 PSTN Phone Calls using the Phone App: “Voice Minutes” ..... 7.6.1 The Native Telephone App ..... 7.6.2 Speech Digitized and Packetized in the Phone ..... 7.6.3 Radio Frequency Modem ..... 7.6.4 Antenna ..... 7.6.5 The Base Station ..... 7.6.6 Backhaul to Mobile Switch and Call Routing ..... 7.6.7 Speech Coding Standards and Bit Rates ..... 7.6.8 Connection to the PSTN 7.7 Mobile Internet: “Data Plan” ..... 7.7.1 Cellphone as a Tethered Modem ..... 7.7.2 Mobile Wi-Fi Hotspot ..... 7.7.3 Packet Relay to the Internet ..... 7.7.4 Dongles ..... 7.7.5 Smartphone as the Terminal ..... 7.7.6 Billing Plans and Roaming ..... 7.7.7 The Holy Grail of Convergence 7.8 Mobile Operators, MVNOs and Roaming 7.9 3G: CDMA and HSPA ..... 7.9.1 IMT-2000 ..... 7.9.2 1X or CDMA2000: IMT-MC ..... 7.9.3 UMTS or W-CDMA: IMT-DS ..... 7.9.4 Data-Optimized Carriers: HSPA and EV-DO ..... 7.9.5 The End of the Standards War 7.10 4G LTE: Mobile Broadband ..... 7.10.1 Universal Terrestrial Radio Access Network Long-Term Evolution ..... 7.10.2 Radio Resource Controller ..... 7.10.3 OFDM ..... 7.10.4 3GPP Standards Committees ..... 7.10.5 Qualcomm Patents 7.11 5G NR: Enhanced Mobile Broadband, IoT Communications 7.12 Spectrum-Sharing Roundup: FDMA, TDMA, CDMA, OFDMA 7.13 3.5-GHz Fixed Wireless Broadband Home Internet 7.14 Wi-Fi: 802.11 Wireless LANs ..... 7.14.1 System Components ..... 7.14.2 Service Set ID ..... 7.14.3 Unlicensed Radio Bands ..... 7.14.4 Half-Duplex ..... 7.14.5 802.11b and g ..... 7.14.6 802.11a ..... 7.14.7 Wi-Fi 4: 802.11n ..... 7.14.8 Wi-Fi 5: 802.11ac ..... 7.14.9 Wi-Fi 6: 802.11ax ..... 7.14.10 VoIP over Wireless LANs ..... 7.14.11 Wi-Fi Security 7.15 Communication Satellites ..... 7.15.1 Transponders ..... 7.15.2 Geosynchronous Orbit ..... 7.15.3 Low Earth Orbit ..... 7.15.6 Starlink
IP Network Quality: CoS, QoS, MPLS and SLAs This module focuses on the network service provided by carriers to move VoIP packets, and how network traffic is identified, managed and prioritized, resulting in Class of Service offerings to meet Service Level Agreements. You will learn about Service Level Agreements, how carriers use MPLS to manage flows of packets, Differentiated Services: different transmission characteristics for different kinds of traffic, and Classes of Service (CoS). VoIP Module 6 Detailed Outline 6. IP Network Quality: CoS, QoS, MPLS and SLAs 6.1 Virtual Circuit Technologies ...... 6.1.1 Packet-by-Packet Routing ...... 6.1.2 Virtual Circuits ...... 6.1.3 Centralized Control of Routing Tables ...... 6.1.4 Prioritization ...... 6.1.5 MPLS Replaces Legacy Technologies 6.2 MPLS ...... 6.2.1 MPLS to Implement Virtual Circuits ...... 6.2.2 Labels and Forwarding Equivalent Classes ...... 6.2.3 Label Stacking ...... 6.2.4 Label-Switched Path Calculation ...... 6.2.5 Label-Switching Routers and Label Processing ...... 6.2.6 User-Network Interface: IP 6.3 Differentiated Services (Diff-Serv) ...... 6.3.1 Different Transmission Characteristics ...... 6.3.2 Classification ...... 6.3.3 Implementation 6.4 Meters, Markers, Shapers and Droppers ...... 6.4.1 Traffic Management ...... 6.4.2 Traffic Management Functions 6.5 Interworking Diff-Serv and MPLS ...... 6.5.1 Similarities between MPLS and Diff-Serv ...... 6.5.2 Diff-Serv Codepoint in MPLS Header ...... 6.5.3 Diff-Serv Codepoint Associated with Label 6.6 Using 802.1P for QoS ...... 6.6.1 Frame-Level Priority Tag ...... 6.6.2 802.1P as an Input to DS Classification 6.7 Implementing CoS: Queuing Techniques ...... 6.7.1 Implementing Prioritization ...... 6.7.2 Priority Queuing ...... 6.7.3 Weighted Round-Robin Queuing
Legacy Datacom Technology: X.25, Frame Relay and ATM This module describes data communication and networking technologies that were formerly mainstream but no longer in wide use, if at all. The idea of a virtual circuit, called a Forwarding Equivalence Class in MPLS lingo, goes all the way back to the 1960s and X.25 data packet networks, which all telephone companies built and sold services on. Envoy-100 email from Bell Canada ran over Datapac; parts of the Internet ran over TymeNet in the very early days, both were commercial X.25 networks. Access speeds to X.25 were 1.2 kb/s dial-up modem or for the institutional customer, 56 kb/s data circuit. The latency, i.e. delay caused by the network, was outlandishly long compared to today's networks. Frame Relay was a speed improvement over X.25, mostly running at 1.5 Mb/s, but did not come with a guarantee of maximum latency and maximum packet loss necessary to be able to guarantee voice quality when communicating phone calls in packets over Frame Relay. Asynchronous Transfer Mode (ATM) was supposed to be the answer to all of our problems, carrying phone calls, television, data and Internet traffic together with suitable guarantees for each. But it got so ridiculously complicated and expensive, it got thrown away and replaced with what we have today: IP packets with MPLS to implement virtual circuits. In this module are the three predecessors to IP/MPLS. And lest we forget, "Asynchronous Ports" on PCs to connect modems and mice, communicating one byte at a time: start bits, stop bits and parity checking. Telecom 101 Module 19 Detailed Outine 19 Legacy Datacom Technology: X.25, Frame Relay and ATM 19.1 “Asynchronous”: Start/Stop/Parity ...... 19.1.1 Asynchronous Communications ...... 19.1.2 Framing: Start and Stop Bits ...... 19.1.3 Parity Checking 19.2 X.25: Packet-Switching using Virtual Circuits ...... 19.2.1 X.25 Network Structure and Operation ...... 19.2.2 Reliable Network Service: Guaranteed Delivery ...... 19.2.3 Connection-Oriented vs. Connectionless Network Service 19.3 Frame Relay ...... 19.3.1 Elimination of a Layer of Software ...... 19.3.2 Unreliable Service ...... 19.3.3 Network Structure and Operation ...... 19.3.4 No Guarantees for Voice 19.4 ATM ...... 19.4.1 Future-Proof Technology (Not) ...... 19.4.2 ATM Cells ...... 19.4.3 Service Classes
Wireless 101 delivers the core technical knowledge needed by anyone serious in the wireless business today. A great deal of Wireless 101 is devoted to mobile communications, because one of the great things about wireless is you can move around while communicating, and people are willing to pay cold hard cash for it. If you added up all of the industry associated with mobile communications: everything from selling handsets and providing customer service, all of the people who work for the carrier, the trucks they buy, people getting jobs as riggers installing equipment on towers, the insurance they have to pay for – the mobile communications industry shows up as part of the gross domestic product of every country in the world. Bluetooth and Wi-Fi are now an indispensable part of everyday life including in-building Internet access and connecting your phone to your car as soon as you get close to it. In July 2022, Starlink was delivering download rates bursting up towards 1 Gb/s to remote areas for $120 per month. This brings Broadband To The Remote Masses in one fell swoop, and will surely boost the quality of life and economic activity worldwide. So that’s covered too. Part 1: Wireless Fundamentals The first part of Wireless 101 is Wireless Fundamentals, five chapters that set the foundation, with radio fundamentals and spectrum, how modems are used to move bits, and radio penetration, propagation and fading. Part 2: Mobile Communications The second part of Wireless 101 is Mobile Communications, fourteen chapters on mobility and mobile communications from A-Z, beginning with the ideas of cellular radio, handoffs, how PSTN phone calls (“Voice minutes”) are implemented, and how Mobile Internet (“Data plan”) is implemented. We’ll explain the technologies: FDMA, TDMA, CDMA, OFDMA, the generations, and LTE and 5G New Radio, including millimeter-wave Ultra Broadband and low-bit-rate 5G services for IoT. Part 3: Fixed Wireless In the third part of Wireless 101, we’ll cover other radio systems, primarily fixed wireless, where the question of continuous communications while driving down the highway doesn’t come into play so much. We’ll cover Wi-Fi: wireless LANs, standards and security, Bluetooth, broadband wireless home Internet, point-to-point, Low-Power Wide-Area Networks, and finish with satellite communications and Starlink.
Optional Wireless Module 5: Legacy 2G and 3G TDMA and CDMA These sections started off their lives in Wireless Module 3, as they were one after another in turn the latest and greatest mobile communication technology. Now in the dustbin of history. Recommended reading for anyone who wants to know • what "GSM" really means: a 2G TDMA technology, • what CDMA is and how it works • the idea of spread spectrum • about the 2G and 3G standards wars of the 2000s Optional Wireless Module 5 Detailed Outline 5 Legacy 2G and 3G: TDMA and CDMA 5.1 Second Generation: Digital ...... 5.1.1 Spectrum ...... 5.1.2 Incompatible Spectrum-Sharing Technologies ...... 5.1.3 CDMA: IS-95 ...... 5.1.4 TDMA: IS-136 ...... 5.1.5 GSM 5.2 TDMA (IS-136) Time-Division Multiple Access ...... 5.2.1 TDMA ...... 5.2.2 IS-136 and D-AMPS ...... 5.2.3 Capacity Increase ...... 5.2.4 Inefficiency 5.3 TDMA (GSM) ...... 5.3.1 Spectrum-Sharing Method ...... 5.3.2 Inefficiency ...... 5.3.3 Data, GPRS and EDGE ...... 5.3.4 Terminology: Misuse of the Term “GSM Phone” 5.4 CDMA Code-Division Multiple Access ...... 5.4.1 Carriers ...... 5.4.2 Codes ...... 5.4.3 Forward Error Correction ...... 5.4.4 Variable-Rate Coding ...... 5.4.5 Packetized Voice and Data ...... 5.4.6 Qualcomm, IS-95A and IS-95B 5.5 Spread Spectrum ...... 5.5.1 Chips and Chipping Rate ...... 5.5.2 Spreading ...... 5.5.3 Direct Sequence vs. Frequency Hopping ...... 5.5.4 Error Correction ...... 5.5.5 Rake Filters and Multipath 5.6 CDMA Operation and Patents ...... 5.6.1 Communication via Multiple Base Stations ...... 5.6.2 Multipath ...... 5.6.3 Soft Handoffs ...... 5.6.4 Walsh Codes and Pseudonoise ...... 5.6.5 Base Station Identification, Short Codes and Timing ...... 5.6.6 Power Control ...... 5.6.7 Qualcomm 5.7 3G: CDMA 1X, UMTS and HSPA ...... 5.7.1 IMT-2000 ...... 5.7.2 1X ...... 5.7.3 Data-Optimized Carriers ...... 5.7.4 Capitulation
IP Networks, Routers and Addresses This module is devoted to IP, used to implement Layer 3. We begin with IP addressing: IPv4 address classes, subnets, DHCP, static and dynamic addresses, public addresses, private addresses and NAT. We'll use the simplest IP network to explore how routers implement the network by relaying packets from link to link, and also act as a point of control to deny communications based on IP address and/or port number. We’ll complete the chapter with IPv6 addressing. Telecom Module 14 Detailed Outline 14 IP Networks, Routers and Addresses 14.1 Definition of Network 14.2 IPv4 Address Classes ...... 14.2.1 Packets and Network Addresses ...... 14.2.2 Historical Network Classes ...... 14.2.3 Class A, B and C ...... 14.2.4 Network ID and Host ID ...... 14.2.5 Class D and E ...... 14.2.6 Dotted-Decimal Notation 14.3 Subnets and Classless Inter-Domain Routing 14.4 DHCP ...... 14.4.1 Dynamic Addresses for Clients ...... 14.4.2 Static Addresses and DNS for Servers ...... 14.4.3 DHCP Client – Server Communications ...... 14.4.4 DHCP Message Exchange ...... 14.4.5 Lease Expiry ...... 14.4.6 DHCP to Assign Static Addresses 14.5 Assigning Subnets to Broadcast Domains 14.6 IP Network: Routers Connected with Point-to-Point Circuits ...... 14.6.1 Broadcast Domain at Each Location ...... 14.6.2 Edge Router at Each Location ...... 14.6.3 Default Gateway ...... 14.6.4 Packet Creation ...... 14.6.5 Packet Transmission from the Source ...... 14.6.6 IP to MAC Address Resolution Protocol (ARP) ...... 14.6.7 Packet Routing ...... 14.6.8 Overbooking & Bandwidth on Demand 14.7 Routers and Customer Edge ...... 14.7.1 Customer Edge Device ...... 14.7.2 Router Connects Broadcast Domains ...... 14.7.3 Routing ...... 14.7.4 Denying Communications ...... 14.7.5 Packet Filtering ...... 14.7.6 Port Filtering ...... 14.7.7 Firewall 14.8 Public and Private IPv4 Addresses ...... 14.8.1 Public Addresses ...... 14.8.2 Regional Internet Registries ...... 14.8.3 Unassigned or Private Addresses 14.9 Network Address Translation ...... 14.9.1 Network Address Translator ...... 14.9.2 Outbound ...... 14.9.3 Inbound ...... 14.9.4 Advantages of NAT ...... 14.9.5 Implementation 14.10 TCP and UDP 14.11 IPv6 ...... 14.11.1 Expanded Addressing Capabilities ...... 14.11.2 Header Simplification ...... 14.11.3 Improved Support for Extensions and Options ...... 14.11.4 Support for Traffic Management ...... 14.11.5 IPv6 Packet Format 14.12 IPv6 Address Allocation and Address Types ...... 14.12.1 Internet Registry Identification ...... 14.12.2 Sites and Global Routing Prefix ...... 14.12.3 Interface ID ...... 14.12.4 Subnet ID ...... 14.12.5 Allocation ...... 14.12.6 Subnet Prefix ...... 14.12.7 IPv6 Address Types
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. We'll explore the most commonly-used structure, 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, and gain a true understanding of how a protocol stack works for applications like web surfing and VoIP. Telecom Module 12 Detailed Outline 12 OSI Layers and Protocol Stacks 12.1 Protocols and Standards ..... 12.1.1 Functions To Be Performed ..... 12.1.2 Monolithic vsStructured Protocols ..... 12.1.3 Open Systems and Standards 12.2 ISO OSI Reference Model ..... 12.2.1 Layers ..... 12.2.2 Separability of the Layers ..... 12.2.3 Protocol Stacks 12.3 The OSI 7-Layer Model 12.4 Physical Layer: 802.3, DSL, DOCSIS, Wireless 12.5 Data Link Layer: 802 MAC ..... 12.5.1 LANs, Frames and Layer 2 Switches ..... 12.5.2 MAC Frames and MAC Addresses ..... 12.5.3 Other Data Link Protocols 12.6 Network Layer: IP and MPLS ..... 12.6.1 Packet-Switched Networks ..... 12.6.2 Routing Table Updates ..... 12.6.3 MPLS 12.7 Transport Layer: TCP and UDP ..... 12.7.1 Reliability ..... 12.7.2 Port Numbers 12.8 Session Layer: POP, SIP, HTTP ..... 12.8.1 Password Authentication ..... 12.8.2 Authentication Servers ..... 12.8.3 Password Caching ..... 12.8.4 Cookies ..... 12.8.5 Client-Server Sessions ..... 12.8.6 Peer-Peer Sessions 12.9 Presentation Layer: ASCII, Encryption, Codecs 12.9.1 Character Coding ..... 12.9.2 E-Mail Coding ..... 12.9.3 Codecs ..... 12.9.4 Data Compression ..... 12.9.5 Symmetric Encryption: Private Key ..... 12.9.6 Asymmetric Encryption: Public Key Encryption and Digital Signatures ..... 12.9.7 Example of Separability of Layers ..... 12.9.8 Example of Peer Protocol 12.10 Application Layer: SMTP, HTML, English … ..... 12.10.1 Email ..... 12.10.2 More Application Layer Examples 12.11 Protocol Stacks ..... 12.11.1 Example: Web Surfing ..... 12.11.2 Voice over IP 12.12 Protocol Stack in Operation: Ukrainian Dolls ..... 12.12.1 Communications Flow ..... 12.12.2 Segmentation at Each Layer ..... 12.12.3 Nested Headers 12.13 Standards Organizations ..... 12.13.1 ISO ..... 12.13.2 DOD and IETF ..... 12.13.3 ITU and Bellcore ..... 12.13.4 TIA and IEEE ..... 12.13.5 3GPP ..... 12.13.6 ANSI
Telecom Fundamentals In this module, we’ll ensure you have a solid foundation in the fundamental ideas of telecom: • The elements of a circuit; • Terminals, clients, servers and peers; • How bits are represented on fiber with pulses; and • How bits are represented with modems on wireless, cable TV and DSL Then we’ll understand how a circuit's capacity is shared to carry many users’ traffic on common facilities: Frequency Division Multiplexing, Time Division Multiplexing, and Bandwidth on Demand: efficient sharing, involving packets, routers and overbooking the network core. Telecom Module 2 Detailed Outline 2 Telecom Fundamentals 2.1 Communication Circuit Model ...... 2.1.1 Information Theory ...... 2.1.2 ITU Model: DTEs and DCEs 2.2 Terminals, Clients, Servers and Peers ...... 2.2.1 Dumb Terminal and Remote Host ...... 2.2.2 Client-Server ...... 2.2.3 Peer-to-Peer 2.3 Representing Bits on Digital Circuits: Pulses ...... 2.3.1 Two-State Transmission Systems ...... 2.3.2 Range Limiting Factors ...... 2.3.3 Repeaters ...... 2.3.4 Comfort Noise Generation 2.4 Representing Bits in Frequency Channels: Modems ...... 2.4.1 Passband Channels ...... 2.4.2 Carrier Frequencies ...... 2.4.3 Modulation ...... 2.4.4 “Press 1 to Understand How Modems Work” ...... 2.4.5 Radio-Frequency Modems ...... 2.4.6 CDMA and OFDM ...... 2.4.7 ASK, FSK, PSK, QAM and QPSK 2.5 Serial and Parallel ...... 2.5.1 Serial Ports: USB, LAN, SATA ...... 2.5.2 Serial in Parallel for High Bit Rates 2.6 Sharing: Frequency-Division Multiplexing ...... 2.6.1 Baseband vsFrequency-Shifted ...... 2.6.2 Coax, Radio and Fiber ...... 2.6.3 Parallel 2.7 Sharing: Time-Division Multiplexing ...... 2.7.1 Synchronous TDM Channels ...... 2.7.2 Trunk Carrier Systems ...... 2.7.3 T1, SONET and SDH ...... 2.7.4 Other TDM Implementations: PONs, GSM, CAN-BUS 2.8 Efficient Sharing: Statistical Time Division Multiplexing ...... 2.8.1 Bandwidth on Demand ...... 2.8.2 Packet Switching 2.9 Overbooking: Reducing User Cost
Introduction to Broadband Converged IP Telecommunications Convergence • Broadband • Network Core and Edge • Protocols • Last Mile Network Access • Residential, Business and Wholesale Services • Network Equipment • Carrier Connections Introduction to Broadband Converged IP Telecommunications is a high-level wide-ranging introduction to the world of modern telecommunications. The selection of topics, their order of presentation and plain-English explanations are proven content, based on instructor-led training courses that are constantly updated to be the core knowledge required in the business. This first Telecom 101 Module is based on the first chapter of Teracom Training Institute’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-Engineering professionals to be a first pass through the topics, 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… without bogging down in details on any particular topic. In subsequent modules, we’ll take another pass and drill deeper into key areas like Wireless, VoIP, PSTN, Ethernet, IP and MPLS. We begin with a comprehensive big-picture introduction to broadband telecom: the concepts of convergence and broadband, today’s telecom network, the parts of the network, the three key technologies: Ethernet, IP and MPLS, what they are and what each does. You’ll learn how a circuit is implemented end-to-end, and identify today’s standard residential, business and wholesale services. Module Outline 1. History of Telecommunications Establishment of Local and Long-Distance Telephone Companies. 2. Convergence One network carrying all services: telephone, video and Internet. Channels vs. packets. 3. Broadband Bandwidth, and how much “broad” might be. 4. Introduction to Broadband Converged IP Telecom Model Graphical model identifying all the main aspects of telecommunications and how they relate. 5. The Network Core High-capacity, high-availability connections between aggregation centers. Fiber rings. 6. Network Protocols: Ethernet, IP and MPLS Ethernet moves packets point-to-point. IP address is the final destination. MPLS manages flows. 7. Network Access: The Last Mile Twisted pair, hybrid fiber-coax, Passive Optical Network, Optical Ethernet, cellular, satellite. 8. Anatomy of a Service Network access technology, network connection type and billing agreement. 9. Services: Residential, Business and Wholesale Comprehensive review of the main dollar-value services in each sector. 10. Network Equipment Layer 2 switches, IP routers, MPLS routers, FDM and TDM multiplexers, wavelength cross connects. 11. Carrier Network Interconnect Tariffed switched-access for calls involving a PSTN phone number; Internet Exchange transit and peering. Prerequisites None. Module Objectives: What You Will Learn After taking this module, you will be able to: - Define convergence, and two ways that it might be achieved - Define bandwidth, explain what broadband means and how much “broad” might be - Identify all of the main aspects of the modern broadband converged IP network, including the parts of the physical network, the three types of services, the equipment and players - Describe the network core, its purpose, performance requirements and how they are implemented - Identify the three primary network protocols: Ethernet, IP and MPLS, and what each does - Explain how MAC Frames and IP Packets go together - Identify the essential purpose of an IP address - Explain the essential advantage of MPLS over IP for routing - Define the three main technology areas for network access - List the most popular technologies in each - Describe the three components of a network service - Define the three main groupings of telecom services based on customer type - Describe at least four different meanings of the term VPN - Differentiate between streaming video vs. video from your ISP, and the essential difference between them - Explain in general what an MPLS VPN is and who uses it - Identify the key difference between MPLS VPN services and SD-WAN services - Explain what SIP trunking is and what legacy service it replaces - List at least four types of wholesale telecommunications services - Explain what a Data Center is - Explain the essential function of a router - Describe what a Layer 2 switch is used for, and how Layer 2 switches relate to routers - Define multiplexing - Identify three technologies that use Frequency-Division Multiplexing - Identify the name for FDM in the fiber optic world - Differentiate between FDM and Time-Division Multiplexing - Describe what a gateway is and the two functions it performs - Identify the two main ways that carriers connect, and where this happens This is quite a range of knowledge, and can appear daunting, especially if you are new to telecom. Keep in mind that this module is the introduction, the first pass through all of these topics. No-one is expecting anyone to be an instant expert. In subsequent modules, we take a second and sometimes third pass through the topics and drill deeper to more fully understand the concepts and technologies. With this module, we’re getting started identifying and understanding all of the aspects of modern broadband converged IP telecommunications. Detailed Outline Telecom Module 1 1 Introduction to Broadband Converged IP Telecommunications 1.1 History of Telecommunications .... 1.1.1 Invention of the Telephone .... 1.1.2 Local Phone Companies .... 1.1.3 The Bell System .... 1.1.4 The Public Switched Telephone Network (PSTN) .... 1.1.5 Consolidation .... 1.1.6 Broadband Carriers .... 1.1.7 Canadian Telegraph Companies .... 1.1.8 Canadian Telephone Companies .... 1.1.9 The Rest of the World .... 1.1.10 New Technologies and New Players 1.2 Convergence .... 1.2.1 Network Sharing Strategies .... 1.2.2 ISDN: Fail .... 1.2.3 ATM: Fail .... 1.2.4 IP: Third Time is the Charm 1.3 Broadband .... 1.3.1 How Many Bits per Second is “Broadband”? .... 1.3.2 4K Guilty Dog Videos .... 1.3.3 Universal Service 1.4 Today’s Converged Telecom Network .... 1.4.1 Common Carriers .... 1.4.2 Core .... 1.4.3 Access .... 1.4.4 Edge .... 1.4.5 Residential, Business and Wholesale Services .... 1.4.6 Data Centers 1.5 The Network Core .... 1.5.1 Rings 1.6 Network Protocols: Ethernet, IP and MPLS .... 1.6.1 Optical Ethernet Links .... 1.6.2 IP Packet Routing Between Links .... 1.6.3 MPLS Traffic Management 1.7 Network Access: The Last Mile .... 1.7.1 Twisted Pair Loops .... 1.7.2 Coax .... 1.7.3 Fiber to the Residenc.... PONs .... 1.7.4 Wireless: Fixed and Mobile 1.8 Anatomy o.... Service .... 1.8.1 Access Circuits .... 1.8.2 Circuit-Terminating Equipment .... 1.8.3 Network Connection Type 1.9 Inside the Network Cloud .... 1.9.1 Core .... 1.9.2 Edge 1.10 Network Edge Equipment .... 1.10.1 Multiplexers: TDM, FDM and WDM .... 1.10.2 Legacy Circuit Switches .... 1.10.3 Route.... Laye.... Switch 1.11 Interconnect to Other Carriers .... 1.11.1 The ILEC .... 1.11.2 Toll Switches, Toll Centers and POPs .... 1.11.3 Switched Access Tariff .... 1.11.4 Internet Traffic Interconnections .... 1.11.5 Business Service Interconnections 1.12 Services .... 1.12.1 Residential Services .... 1.12.2 Business Services .... 1.12.3 Wholesale Services Let's go!
Wireless Fundamentals Radio fundamentals • Spectrum • Digital radio • Modems and Modulation • Propagation, Penetration and Fading Wireless Fundamentals is the first module in the Wireless series. We begin with the basics: what radio is, how it's organized and how and it's used to communicate information. We'll understand how radio frequencies are in the Gigahertz range, used within frequency bands measured in the Megahertz wide. Then we will look at the spectrum, i.e. standardized bands of frequencies, how they are allocated and the need for licenses. You will learn which bands are used for what, from cordless phones to Wi-Fi and cellular, including new allocations in 600, 700 and 800 MHz bands, 3.5 GHz fixed wireless, and new allocations for 5G including the 3.7 GHz C-band... and how some aircraft operators learned the meaning of "spectrum clearing". Next, we'll understand how information is represented using radio. The first stop is a quick review of old-fashioned analog radio and TV, followed by what most systems use today: digital. We'll spend some time understanding digital, how 1s and 0s are communicated by modems and familiarize you with jargon and buzzwords like QAM and QPSK. We'll finish off with radio transmission issues, including propagation, penetration and fading. Wireless Module 1 Detailed Outline 1 Wireless Fundamentals 1.1 Radio ...... 1.1.1 Definition of “Radio” ...... 1.1.2 Applications for Radio ...... 1.1.3 Representing Information Using Radio 1.2 Wireless Spectrum and Radio Bands ...... 1.2.1 The Need for Regulation ...... 1.2.2 Spectrum ...... 1.2.3 Capacity vs. Performance Tradeoff ...... 1.2.4 Frequency Bands ...... 1.2.5 Broadcast Television ...... 1.2.6 Repurposing of Broadcast Television Spectrum ...... 1.2.7 Two-Way Radio: FDD or TDD ...... 1.2.8 600 MHz Band ...... 1.2.9 700 MHz Band ...... 1.2.10 800, 900, 1800 and 1900 MHz bands ...... 1.2.11 Unlicensed Bands ...... 1.2.12 2.5 GHz Band ...... 1.2.13 3.5 GHz Band ...... 1.2.14 3.7 GHz C-Band 5G ...... 1.2.15 Millimeter-Wave Bands 1.3 Analog Radio ...... 1.3.1 Definition of Analog ...... 1.3.2 Carrier Frequency for Radio ...... 1.3.3 AM, FM and PM 1.4 Digital Radio: Modems ...... 1.4.1 Amplitude Shift Keying ...... 1.4.2 Frequency Shift Keying ...... 1.4.3 Phase Shift Keying ...... 1.4.4 Baud Rate ...... 1.4.5 More Signals = More Bits ...... 1.4.6 QPSK: 2 Bits per Signal ...... 1.4.7 QAM ...... 1.4.8 Limits ...... 1.4.9 Summary 1.5 Propagation, Penetration and Fading ...... 1.5.1 Propagation ...... 1.5.2 Omni Antennas ...... 1.5.3 Directional Antennas and Sectorization ...... 1.5.4 Attenuation and Carrier-to-Noise Ratio ...... 1.5.5 Fading ...... 1.5.6 Interference
VoIP Architectures and Implementation Choices Is a comprehensive overview of the many flavors of VoIP, comparing and contrasting the various implementation and architecture choices. Progressing from talking between computers over the Internet, through Internet telephony, VoIP from carriers, PBX replacement with call manager / softswitch systems, Hosted PBX and Cloud Services, to IP Centrex, we’ll deliver to you the knowledge to confidently differentiate VoIP architectures and discuss pros and cons of different options. VoIP Module 2 Detailed Outline 2. VoIP Architectures and Implementation Choices 2.1 Internet Telephony: Computer-Computer VoIP over the Internet ...... 2.1.1 Voice in Packets Over The Internet ...... 2.1.2 Call Setup ...... 2.1.3 Voice Quality ...... 2.1.4 Proprietary Web Phone Apps 2.2 Proprietary Internet Telephony Example: Skype ...... 2.2.1 Proprietary Internet Telephony ...... 2.2.2 Communicating to the Skype App Behind a NAT ...... 2.2.3 Proprietary Closed Ecosystems 2.3 VSPs: Internet to Phone ...... 2.3.1 Voice over IP Service Providers ...... 2.3.2 Connection to the Telephone Network ...... 2.3.3 VSP Gateway Required 2.4 VSP: Phone to Phone over the Internet e.g. Vonage ...... 2.4.1 POTS Telephones for VoIP ...... 2.4.2 Adapter ...... 2.4.3 Differences from POTS 2.5 VoIP Is The New POTS ...... 2.5.1 VoIP From The LEC ...... 2.5.2 Not Internet Communications 2.6 VoIP at Carriers ...... 2.6.1 Migrating to an All-IP Network ...... 2.6.2 Ending Switched-Access Tariffs 2.7 VoIP-Enabled PBX and Migration Options ...... 2.7.1 Choices for Business VoIP Systems ...... 2.7.2 Critical Operations Infrastructure ...... 2.7.3 Upgrading a PBX ...... 2.7.4 Migration Plan ...... 2.7.5 TDM over IP: Legacy Equipment Support ...... 2.7.6 Handset Gateways and BORSCHT ...... 2.7.7 Guinea Pigs 2.8 PBX Replacement: Premise Softswitch ...... 2.8.1 Call Manager ...... 2.8.2 Essential Function ...... 2.8.3 Special-Purpose Premise Hardware ...... 2.8.4 Standards-Based? ...... 2.8.5 Many Names ...... 2.8.6 Capabilities ...... 2.8.7 System Architectures ...... 2.8.8 Redundancy and Critical Functioning 2.9 Cloud Services and Hosted PBX: Softswitch as a Service (SaaS) ...... 2.9.1 Cloud Services ...... 2.9.2 Customer Management ...... 2.9.3 Additional Features ...... 2.9.4 Numerous Advantages ...... 2.9.5 Disadvantages 2.10 IP Centrex ...... 2.10.1 Outsourcing Everything To The Phone Company ...... 2.10.2 Advantages over Legacy Centrex ...... 2.10.3 Many Service Providers and Features ...... 2.10.4 Cost Structure 2.11 Asterisk and Open-Source Softswitch Software ...... 2.11.1 Open-Source Software ...... 2.11.2 Asterisk and sipX ...... 2.11.3 Advantages ...... 2.11.4 Disadvantages 2.12 IP Phone Features and Uses ...... 2.12.1 VoIP Phone Components ...... 2.12.2 Functions ...... 2.12.3 Numerous Methods for Dialing ...... 2.12.4 Special Features and Customization
Voice Packetization, Codecs and Voice Quality The "nuts and bolts" of Voice over IP: • How voice is digitized and coded, • Time stamps applied with the RTP protocol, and • How the result is carried in UDP, IP packets and MAC frames. You'll learn about codecs and compression, and understand factors like delay, jitter and packet loss, what causes them, and how they affect sound quality. VoIP Module 4 Detailed Outline 4. Voice Packetization, Codecs and Voice Quality 4.1 Voice Packetization ...... 4.1.1 Microphone Produces a Voltage Analog ...... 4.1.2 Digitization ...... 4.1.3 Coding ...... 4.1.4 Segmentation and Packetization 4.2 Measuring Voice Quality ...... 4.2.1 Mean Opinion Score ...... 4.2.2 Toll-Quality Speech 4.3 Factors Affecting Voice Quality ...... 4.3.1 Codec, Delay, Jitter and Packet Loss ...... 4.3.2 Network Load 4.4 Codecs and Compression ...... 4.4.1 Coder / Decoder ...... 4.4.2 Tradeoffs ...... 4.4.3 CBR vs. VBR ...... 4.4.4 Standards 4.5 Delay ...... 4.5.1 Coding Delay ...... 4.5.2 Network Delay ...... 4.5.3 Design Goal 4.6 Jitter ...... 4.6.1 IP: No Guarantees ...... 4.6.2 Variable Delivery Time ...... 4.6.3 Variable Network Loading ...... 4.6.4 Jitter Buffer 4.7 RTP ...... 4.7.1 Real-Time Transport Protocol ...... 4.7.2 Segmentation ...... 4.7.3 Time Stamp ...... 4.7.4 Error Recovery 4.8 VoIP Protocol Stack: RTP, UDP, IP, MAC ...... 4.8.1 Moving the RTP PDU ...... 4.8.2 UDP Error Detection and Recovery ...... 4.8.3 Port Number ...... 4.8.4 RTP/UDP/IP/Ethernet Protocol Stack ...... 4.8.5 Header Compression 4.9 Packet Loss ...... 4.9.1 Packet Loss Mechanism ...... 4.9.2 Recovery 4.10 Tips for Maximizing Voice Quality ...... 4.10.1 Network Level Testing ...... 4.10.2 VoIP Application Level Testing ...... 4.10.3 Strategies
SIP, Softswitches, and VoIP Call Setup This module is all about SIP, and how it is used to set up phone calls. You will understand: • What SIP is, • How it works, • Jargon like URI, proxy server and location server, and • How SIP fits in with softswitches and call managers. We'll trace the establishment of a VoIP phone call using SIP and DNS, step by step. VoIP Module 3 Detailed Outline 3. SIP, Softswitches and VoIP Call Setup 3.1 What SIP Is and What It Can Do ...... 3.1.1 The Session Initiation Protocol ...... 3.1.2 The Essential Function ...... 3.1.3 Supports Five Aspects of Communications ...... 3.1.4 SIP Servers: Proxies ...... 3.1.5 SIP Addresses 3.2 Relationship to Other Protocols ...... 3.2.1 Layer 5 of the OSI Model ...... 3.2.2 Session Description Protocol ...... 3.2.3 What SIP Doesn’t Do 3.3 SIP URIs: “Telephone Numbers” ...... 3.3.1 Uniform Resource indicators ...... 3.3.2 Address of Record ...... 3.3.3 Relating URIs to Telephones ...... 3.3.4 Not Just Telephones ...... 3.3.5 DNS Lookup ...... 3.3.6 URI Structure ...... 3.3.7 Encryption 3.4 Register: Update The Location Database ...... 3.4.1 First, Registration ...... 3.4.2 Location Database ...... 3.4.3 Call Disposition Rules and Filters 3.5 INVITE: “Dialing” and Outbound Proxy ...... 3.5.1 Dialing ...... 3.5.2 Outbound Proxy 3.6 Location Service: Finding the Far End ...... 3.6.1 Far-End Proxy ...... 3.6.2 Call Disposition ...... 3.6.3 Ringing ...... 3.6.4 Answer ...... 3.6.5 Call Type or Media Negotiation 3.7 The SIP Trapezoid ...... 3.7.1 Getting Ready To Send and Receive Calls ...... 3.7.2 Establishing a Call 3.8 SIP Messages and Session Description Protocol ...... 3.8.1 Plain Text Messages ...... 3.8.2 Message Type, Header and Payload 3.9 How SIP Relates to Softswitches and Call Managers ...... 3.9.1 SIP Software ...... 3.9.2 Authentication, Authorization and Accounting Software ...... 3.9.3 Voicemail and Other Features
Certification study guide and companion reference textbook for the TCO Certified VoIP Analyst (CVA) courses and exams. The CVA Study Guide corresponds directly to the CVA online courses and exams. For each lesson, detailed text notes are provided along with the main graphic. Many people find they learn better with a companion book. Printed in color! Get a complete understanding of Voice over IP and SIP, with CVA Certification to prove it. CVA covers all aspects of Voice over IP, including all the different ways VoIP is implemented, how calls are set up with softswitches and SIP, how voice is packetized and the factors affecting sound quality, connecting to carriers and SIP trunking, and network quality with MPLS, Service Level Agreements and Class of Service. The Certified VoIP Analyst Certification includes six online courses and exams: 2221 Fundamentals of Voice over IP 2222 VoIP Architectures and Implementation Choices 2223 Softswitches, SIP, Call Setup and SIP Trunking 2224 Voice Packetization, Codecs and Voice Quality 2225 SIP Trunking and Carrier Connections 2226 IP Network Quality: CoS, QoS, MPLS AND SLAs This knowledge enables a CVA to stand out from the rest, with demonstrated broad and deep vendor-agnostic knowledge of VoIP systems and best practices. This kind of knowledge enables higher-paying positions performing analysis, writing reports, making recommendations and providing effective, value-added contributions in project management, business and product development, software design, sales, marketing and finance. Invest in yourself with the CVA Certification Package from Teracom Training Institute! The CVA Certification Package Unlimited Plan includes the six CVA online courses and the TCO CVA Certification Exam, both with unlimited repeats – which means guaranteed to pass, and refresh your knowledge anytime. Get up to speed on all major topics, at your own pace. Understand the fundamentals, technologies, jargon, buzzwords and most importantly, the underlying ideas ... and how it all fits together. Plus, get your Telecommunications Certification Organization (TCO) Certified VoIP Analyst (CVA) Certification to prove it! Upgrade your skills – and your résumé – with this training and certification today!
This book is the study guide and textbook for the TCO Certified Telecommunications Network Specialist (CTNS) Certification, conforming to the lessons in the eight CTNS courses and their exams: 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 The selection of material, its order, timing, and explanations are field-tested to deliver the core knowledge set for today’s telecommunications. The courses deliver a solid foundation of knowledge in broadband, telecom, datacom and networking: the fundamentals, technologies, jargon and buzzwords, standard practices and most importantly, the underlying ideas, and how it all fits together… with TCO Certification to prove it! 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 Wireless Telecommunications, then Introduction to Voice over IP, and The PSTN. The second half of CTNS is four courses focusing on the three main enabling technologies for the modern telecom network: Ethernet, IP and MPLS. We begin with the OSI model and its Layers to establish a framework for understanding what each does and how they work together... and all the other things that have to be done. This book is intended to enhance your learning and retention while taking the online courses. It is also useful as a day-to-day reference handbook and glossary. Our goal is to explain the big picture, the jargon and buzzwords, and put in place a very solid base of telecom knowledge spanning fundamentals to the latest technologies and how they are deployed – in plain English. Let's get started!
In the popular imagination, the notion of military medicine prior to the twentieth century is dominated by images of brutal ignorance, superstition and indifference. In an age before the introduction of anaesthetics, antibiotics and the sterilisation of instruments, it is perhaps unsurprising that such a stereotyped view has developed, but to what degree is it correct? Whilst it is undoubtedly true that by modern standards, the medical care provided in previous centuries was crude and parochial, it would be wrong to think that serious attempts were not made by national bodies to provide care for those injured in the military conflicts of the past. In this ground breaking study, it is argued that both sides involved in the civil wars that ravaged the British Isles during the mid seventeenth century made concerted efforts to provide medical care for their sick and wounded troops. Through the use of extensive archival sources, Dr Gruber von Arni has pieced together the history of the welfare provided by both Parliamentarian and Royalist causes, and analyses the effectiveness of the systems they set up.
This etymological dictionary gives the origins of some 20,000 items from the modern English vocabulary, discussing them in groups that make clear the connections between words derived by a variety of routes from originally common stock. As well as giving the answers to questions about the derivation of individual words, it is a fascinating book to browse through, and includes extensive lists of prefixes, suffixes, and elements used in the creation of new vocabulary.
First published in 1933, this book explores both contemporary and historical slang, focusing on the characteristics and quirks of the English and American languages. As well as looking at commonly used slang, there are sections that give the reader insight into more unusual areas such as Cockney slang, slang in journalism and slang in commerce, as well as slang used by sailors, the law and the church. The book will be of interest to scholars and the general readers who take an interest in language.
Thank you for visiting our website. Would you like to provide feedback on how we could improve your experience?
This site does not use any third party cookies with one exception — it uses cookies from Google to deliver its services and to analyze traffic.Learn More.