Uyless Black is a widely known and respected consultant and lecturer on computer networks and data communications.
With clients throughout the world, including the local and interchange carriers in the USA, Nortel in Canada, and
British Telecom in the UK, he has extensive operations and implementation experience in both public and private
networks.
Preface
Like most of the more recent books I have written, I decided to write this book as part of my ongoing work with
my clients because of the absence of a systematic analysis of the subject matter. In this case, my clients could
not find a book that provided a description and comparison of the new technologies that are appearing in the telecommunications
industry. Generally, some books are available that are accurate, and well-written, but they treat only one, two,
or three of the technologies. Obviously, the problem was not specific to my clients alone, so I decided to prepare
this book for other interested readers as well.
The book is the culmination of a series of lectures I have been conducting in North America and Europe, the fruition
of my lecture notes, and a reflection of ongoing consulting work with my clients. I thank those people who attended
these lectures; in effect, they were my �referees� of the technical content of this book.
The book is intended for readers who are interested in the fields of telecommunications and computer-based networks.
It can also serve as supplemental reading for advanced networking classes in colleges and universities.
My goals in writing this book are threefold. First, I wish to provide the reader a general description of how the
emerging communications technologies operate and where they fit in a computer/communications network and in customer
equipment. Second, I wish to provide the reader with a general comparison of the technologies, their pros and cons,
where they do or do not compete with each other, and their targeted applications. Third, I wish to provide the
reader with a general explanation of the international standards that are published for these emerging communications
technologies. I have attempted to achieve a balance between a detailed and general treatment of the subject matter.
Each technology-specific chapter contains a worksheet that the reader can fill in after reading the chapter. I
have included a completed worksheet with an explanation of the reasons for my answers.
Tutorial information is also provided for the reader� Appendix A is a basic tutorial on communications systems
and networks; Appendix B is a tutorial on layered protocols; Appendix C is a tutorial on management information
bases (MIBs); and Chapter 2 is a tutorial on how to analyze a communications protocol. Even though Chapter 2 can
be considered as a tutorial, I think that it will be useful to all readers, because it provides a systematic approach
to the analysis of communications protocols.
The emphasis of this book is on the wire-based emerging communications technologies, and the principal focus is
on the role of optical fiber in these technologies. The emerging communications technologies using wireless media,
such as cellular and cordless systems, are of such scope to warrant another book. Notwithstanding, for purposes
of comparisons and completeness, I have included an overview of this subject in Chapter 9.
The reader will notice that I have included some topics that could be considered as �old,� not emerging technologies�as
example, frame relay. I chose to include frame relay because, while the underlying technology is not new, the service
offerings are new, and the ideas of committed information rate and traffic tagging, for example, are also new.
The very nature of the subject matter of this book�emerging communications technologies�makes it difficult to write
about the topic as if these systems and protocols were cast in stone. Nonetheless, this book reflects the most
up-to- date information available at the time the book went to press. The latest information from the ATM Forum,
the Frame Relay Forum, the Network Management Forum, the SMDS Interest Groups, the standards groups, and my ongoing
work are included in this book.
Notes for the Reader
The International Telegraph and Telephone Consultative Committee (CCITT) has changed its name to the International
Telecommunication Union-Telecommunication Standardization Sector (ITU-T).
Unless identified otherwise, the term bandwidth is used in this book to describe a channel's capacity in bits per
second, and not a frequency spectrum.
The term NNI is used in this book to mean the network-to- network interface. NNI is also known as the network-node
or node-to-node interface. NNI is supposed to describe a switch-to-switch interface, which could operate within
a network or between networks. The major goal of an NNI is to allow switches from different vendors to interwork
with each other.
The initials ICI mean intercarrier interface, and is used in this book to describe the interface between two networks
operated by different network operators.
Summary
The most complete and up-to-date review of advanced communications technologies -- by Uyless Black, the best-selling author. Communications engineers and professionals know that Uyless Black provides the clearest, most concise explanations of advanced communications technology. This completely revised edition, based on the author's training courses at Bell Operating Companies, Bell Northern and British Telecom, delivers all the information professionals need to understand today's revolutionary communications technologies. Since the first edition of Emerging Communications Technologies was published in September 1995, dramatic changes in communications have taken place, and this book covers them all. New coverage includes: new technology options for residential broadband, advanced wireless technologies such as PCS; evolving carrier technologies such as intelligent networks; and new Internet technologies such as IPv6 and Mbone multicasting. The book also includes detailed coverage of high-speed options such as ATM, B-ISDN, Gigabit Ethernet, and SONET.
New coverage of Gigabit Ethernet, intelligent networks, and advanced Internet features including IPv6, multicasting, and intelligent servers.
Expanded and revised coverage of ATM, SONET, PCS, and mobile/wireless technologies.
Based on author's training courses for engineers at regional Bell companies, Bell Northern and British Telecom.
Completely updated to reflect the most current information available.
Table of Contents
Preface.
1. Introduction.
Introduction. The Need for Enhanced Services. The Past. The Future Has Become the Present. Goals of the Emerging
Communications Technologies. LAN Interconnectivity. A Brief Summary. Need for Greater Communications Capacity.
LAN and WAN Internetworking. Costs of Connecting Dispersed LANs. The Virtual Private Network (VPN). Proposed Solutions.
The Confusion Factor. Fast Relay Systems. Trends in Technology. Hardware and Software. New Technologies: To Use
Them or Not to Use Them? Broadband Networks Broadband Signaling Hierarchies Applications Supported by the New Technologies
New Technologies: Competitive or Complementary? Performance and Distance Considerations. Obtaining Services for
the Networks: Bandwidth on Demand Where Services are Provided. Layered Architectures of the Emerging Technologies.
Summary.
2. Foundations for the Emerging Technologies.
Introduction. Virtual Circuits. A Brief Digression. Permanent Virtual Circuit (PVC). Switched Virtual Circuit
(SVC) or Connection on Demand. Semi-permanent Virtual Circuits (SPVC). Connection-oriented and Connectionless Systems.
Connection-orientated Systems. Connectionless Systems. The Pros and Cons. The Coexistence of Connection-oriented
Systems and Connectionless Systems. Variable Bit Rate (VBR) and Constant Bit Rate (CBR) Applications. VBR Applications.
CBR Applications. Flow Control and Congestion Management. Explicit Flow Control. Implicit Flow Control. No Flow
Control. User Payload Integrity Management. Layered Protocols and Protocol Data Units. Addressing and Identification
Schemes. Multiplexing Methodologies. Switching, Routing, and Relaying. Source and Non-source Routing. Fixed and
Adaptive Routing. Network Interfaces. Convergence, Segmentation, and Reassembly Operations. Summary.
3. Emerged Technologies.
Introduction. T1/E1 CARRIER Systems. The Purpose of T1 and E1. Typical Topology. T1 and E1 Layers. T1/E1 PDUs.
Conclusions on T1/E1. X.25. The Purpose of X.25. Typical Topology. X.25 Layers. X.25 PDUs. Other Noteworthy Aspects
of X.25. Conclusions on X.25. ISDN. The Purpose of ISDN. Typical Topology. ISDN Layers. ISDN PDUs. Conclusions
on ISDN. Signaling System Number 7 (SS7). The Purpose of SS7. Typical Topology. SS7 Layers. SS7 PDUs. Conclusions
on SS7. FDDI. The Purpose of FDDI. Typical Topology. The FDDI Layers. FDDI PDUs. Other Notable Aspects of FDDI.
Conclusion on FDDI. Summary.
4. Frame Relay.
Introduction. The Purpose of Frame Relay. Pertinent Standards. Typical Frame Relay Topology. The Frame Relay
Layers. Frame Relay and Its Relationship to ISDN Layers. OSI and ANSI Layers. The Frame Relay Protocol Data Unit
(PDU). Frame Relay Operations in More Detail. The Frame Relay Core Functions. The Data Link Connection Identifier
(DLCI). Frame Relay Link Layer Error Checking. Potential Congestion Problems. Traffic Management. Consolidated
Link Layer Management (CLLM). The Discard Eligibility Bit. Committed Information Rate. Leaking CIR and Fast Forward
CIR. Classes of Service Using Bc and Be. DLCIs in More Detail. The Frame Relay Network-to-Network Interface (NNI).
NNI Operations. Bellcore Exchange Access FR (XA-FR) PVC Service. Other Notable Aspects of Frame Relay. DLCI Values.
Added Options to Frame Relay. The Local Management Interface (LMI). Frame Relay SVC Operations. Other Quality of
Service (QOS) Options. Internetworking Frame Relay and ATM. Multiprotocol Operations over Frame Relay. The Frame
Relay MIB. Frame Relay Worksheet. Summary.
5. Fast and Switched Ethernet.
Introduction. Generations of LANs. First Generation. Second Generation. Third Generation. Fourth Generation.
Switched Ethernet. Switched Ethernet Architecture. Store and Forward and Cut-through Switches. Virtual LANs. Fast
Ethernet. 100BASET. AnyLAN. Fast/Switched Ethernet Worksheet. Summary.
6. Metropolitan Area Networks (MANs) and Switched Multimegabit Data Service (SMDS).
Introduction. The Purpose of a MAN. Pertinent Standards. A Typical MAN Topology. Topology Reconfiguration with
Self-Healing Networks. The MAN Layers. MAN Protocol Data Units (PDUs). MAN Operations in More Detail. The Access
Unit (AU). Overview of the DQDB Protocol. DQDB Counters. Location Discovery. Segmentation and Encapsulation Operations.
Other Notable Aspects of the MAN. MAN Summary. Introduction to SMDS. The Purpose of SMDS Pertinent Standards. A
Typical SMDS Topology. SMDS Layers. SMDS Protocol Data Units. SMDS Operations in More Detail. Defining and Measuring
Congestion. The Sustained Information Rate (SIR) and Access Classes. SIP Segmentation and Encapsulation Functions.
SNI Quality of Service (QOS) Operations. The Interchange Carrier Interface (ICI). Quality of Service (QOS) Objectives.
Other Notable Aspects of SMDS. SMDS Address Management Operations. The ISSI. The Operations System/Network Element
(OS/NE) Interface (Operations Technology). The SMDS MIB. MAN/SMDS Worksheet. SMDS Summary.
7. Asynchronous Transfer Mode (ATM).
Introduction. The Purpose of ATM. Pertinent Standards. An ATM Topology. The VPI and VCI Labels. ATM Layers.
ATM and the B-ISDN Model. ATM Protocol Data Units (Cells). ATM Operations in More Detail. Physical Layer Interfaces.
ATM over Copper. Rationale for the Cell Size. Network Transparency Operations. ATM Labels. Multiplexing VCIs and
VPIs. ATM Connections on Demand. ATM Switching. Classes of Traffic. AAL Types. Traffic Management in an ATM Network.
ATM Forum and ITU-T Traffic Control and Congestion Control. The ATM B-ISDN Intercarrier Interface (B-ICI). Physical
Layer Requirements at the B-ICI. Traffic Management at the B-ICI. Reference Traffic Loads. B-ICI Layer Management
Operations. Other Notable Aspects of ATM. Addressing in an ATM Network. Network Management. The ATM MIB. ATM Worksheet.
Summary.
8. Synchronous Optical Network (SONET)/Synchronous Digital Hierarchy (SDH).
Introduction. Purpose of SONET/SDH. Synchronous Networks. Pertinent Standards. Typical SONET/SDH Topology. SONET/SDH
Layers. SONET/SDH in More Detail. Automatic Protection Switching (APS). The SDH Multiplexing Structure. Payloads
and Envelopes. Payload Pointers. Examples of Payload Mapping. Mapping and Multiplexing Operations. Error Checking,
Diagnostics, and Restoration. The Control Headers and Fields. SONET/SDH Equipment. Other Notable Aspects of SONET/SDH.
Operation Administration and Maintenance (OAM) Operations. Progress in SONET/SDH Penetration. SONET/SDH Worksheet.
Summary.
9. Mobile Communications Technologies.
Introduction. The Purpose of Mobile Communications Systems. Typical Cellular Systems Topology. Cellular Systems
Operations in More Detail. Cellular System Types and Market Penetration. GSM. GSM Interfaces. Call Routing. Location
Updating. GSM 900/DCS1800: Foundation for PCS 1900 (TDMA). CDMA: A New Arrival into the Commercial Mobile, Wireless
World. TDMA versus CDMA. Cordless Systems Operations in More Detail. CT2. DECT. Other Standardization Efforts for
PCS. The Auctions in the U.S. and the PCS Marketplace. Candidates for PCS Technologies. The Cellular Digital Data
Packet System Specification (CDPD). CDPD Services and Servers. Third-Generation Mobile Systems. Some Concluding
Thoughts. Mobile Communications Systems Worksheet. Mobile Communications Summary.
10. Residential Broadband.
Introduction. The Problem with the Subscriber Loop. The Proposed Solutions: Two Interlocking Approaches, Coding/Modulation
and Wiring. How Much Bandwidth Is Needed to Satisfy the Subscriber? Downstream Bandwidth. Upstream Bandwidth. Beyond
the Coding/Modulation and Wiring: Service Provisions. Switched Digital Video (SDV). Coding and Modulation. HDSL.
ADSL. Wiring at the Local Loop: Subscriber Loop Options. Hybrid/fiber Copper (HFCop). Hybrid/fiber Coax (HFC).
Fiber to the Curb (FTTC) and Fiber to the Home (FTTH). The Wireless Option. Managing the Broadband Signals. Bellcores
TR-303 Specification. Residential Broadband Worksheet. Summary. Appendix 10A: Coding and Modulation Techniques
for Residential Broadband. Introduction. Quadrature Amplitude Modulation (QAM). Examples of Modulation Schemes
and Bit Rates. Carrierless Amplitude/Phase Modulation (CAP).
11. Broadband Signaling Networks.
Introduction. What Are Broadband Signaling Networks? Differences between Broadband and Conventional Signaling
Systems. N-ISDN and B-ISDN. Example of a Broadband Signaling Network Operation. Examples of Services Provided by
the Broadband Network. ISO 9577. ATM Parameters. The Broadband Signaling Protocols. How the Broadband Signaling
Stacks Operate. Broadband Signaling Worksheet. Summary.
12. Advanced Intelligent Network.
Introduction. Operator Services Systems (OSS). The 800 ServiceInklings of an Advanced Intelligent Network (AIN).
Key Aspects of the AIN. The Intelligent Network and the Advanced Intelligent Network. Distribution of Functions.
Evolution to the AIN. Other Parts of the AIN. Example of an AIN Operation. The AIN Basic Call Model. Standardized
Messages. The Private Virtual Network. AIN Worksheet. Summary.
13. Internet Protocol, Version 6 (Ipv6).
Introduction. Functions of the Internet Protocol (Ipv4). The IP Address. Problems with IP and the IP Address.
The Solutionan Expanded IP Address Space. Alternatives to the Overhead of IPv6 Addresses. The Next Generation IPIPv6.
Functions of the IPv4 Header Fields. Functions of the IPv6 Header Fields. IPv6 and ATM. Fixed Routing and Virtual
Circuits. Supporting Different Types of Traffic. The IPv6-ATM Debate. IPv6 Worksheet. Summary.
Appendix A: A Tutorial on Communications Networks.
Introduction. Data Communications Networks. Classifying Networks. Wide Area and Local Area Networks. Network
Components. Voice Networks. Nonhierarchical Routing. History of and Inherent Problems with Coexistence of Analog
and Digital Systems. Analog-to-Digital Conversion. Data Images over Voice Channels. FDM, TDM, and STDM. Circuit,
Message, Packet, and Cell Switching. Network Routing Operations. The Challenge of Integrating Voice, Data, and
Video Applications. Fast Packet Switching (FPS). Hybrid Switching.
Appendix B: Layered Protocols, OSI, and TCP/IP.
Introduction. Protocols and the OSI Model. OSI Layer Operations. The Internet Protocols (TCP/IP). The Internet
Layers. IP Functions. TCP Operations.
Appendix C: Management Information Bases (MIBs).
Introduction. Purpose of a MIB. Examples of MIB Objects and Other Entries.