Home > Articles > Networking > Wireless/High Speed/Optical

This chapter is from the book

The Optical Marketplace

The optical technology is a high-growth market. As Figure 1–5 shows, it is expected to more than double between 2000 and 2003. Most of the growth will be for terrestrial WDM and optical networks, and submarine cable systems. The growth of conventional TDM systems will continue (shown in Figure 1–5 as SONET/SDH, and explained in Chapter 5), but at a lesser rate than the other areas. Optical systems are being incorporated into CATV networks, but this growth will be modest because the coaxial cable plant to the homes cannot be re-wired in a cost-effective manner. A residence does not need the bandwidth of fiber (at least not for the foreseeable future).

Figure 1–5 Worldwide market for optical components.

Figure 1–6 shows another study comparing the projected transmission capacity and the demand through 2004 [STRI01]. The figures pertain to the national backbone in the United States and not to the access loops. This study holds that the building-out of optical networks discussed earlier will provide excess capacity for the early part of this decade, and if one examines the gap between demand and capacity, it is reasonable to expect that capacity will exceed demand well beyond 2004.

Figure 1–6 Demand vs. capacity [STRI01].

There are those in the industry who disagree. They state that the upcoming applications will require huge amounts of bandwidth, and that this supposed excess capacity will be consumed by these applications. There is no question that some applications do indeed require a lot of bandwidth. A prime example is interactive high-quality Web traffic, exhibiting the integration of high-resolution, real-time voice, video, and data.

The Local Loop Bottleneck Must Be Solved

It is my view that the upcoming applications, and their demand for large chunks of bandwidth, are not going to be realized to any large degree until bandwidth is available on the access line (the local loop) to the end user. It does little good to download a Web response to a user at a terabit rate within the network when the vast majority of access lines are restricted to V.90 speeds (56 kbit/s). Certainly, some businesses can afford to purchase large bandwidths from the business to the terabit backbones. But many businesses cannot afford to purchase this bandwidth, nor can the majority of residential users. In addition, broadband access loops are not available to most residences anyway.

The situation in the United States is interesting, and quite frustrating to many customers, because many of them are limited to very low capacity links to the Internet. What is the incentive for the local access providers (the telephone local exchange carriers (LECs), CATV operators, and wireless providers) to expand their local access plant to the megabit or terabit rate? After all, with some minor exceptions (and in spite of the 1984 and 1996 legislative efforts), these companies have a lock on their market. Some people believe that these companies do not have a lot of incentive to invest in the upgrading of their plants.

Maybe so, but the local access providers will expand their plant if they think there is sufficient demand to enable them to make money on their investment. So, beyond the issues of government-sponsored monopolies, is there really that much demand for the deployment of high-capacity systems into the mass marketplace?1 Most Internet users use the Internet for email or simple text-oriented Web retrievals, and many have been conditioned to the slow response time in their interactions with their networks.

The present situation can be illustrated with a diagram shown in Figure 1–7.2 The circle in this figure illustrates the relationships of: (a) user applications' requirements for bandwidth (labeled "Applications" in the figure), (b) the capacity of the user or network computers (labeled "CPU" in the figure), and (c) the capacity of the communications media to support traffic (labeled "Bandwidth" in the figure).

1By mass marketplace, I mean deployment into residences on a large scale, well beyond the 15–20% penetration rate for the current efforts of telephone company and the cable company.

2I call this illustration the "eternal circle," because it shows a seemingly never-ending dependency-relationship between the three components.

Historically, the bottleneck in this circle has varied. At times, it has been the lack of CPU (and memory) capacity in the user's computer. At other times, it has been the lack of capacity in the network to support the capacity requirements of the users' applications.

Figure 1–7 shows the relationships with two-way arrows, which suggests that these three operations are interrelated and dependent upon each other. But which comes first? Does the application's requirement for more capacity lead to faster CPUs and/or the expansion of network bandwidth? Or does the introduction of more bandwidth encourage the development of faster computers and more powerful applications? There are no clear answers to these questions. Sometimes one pushes the other, and at other times the opposite occurs.

Figure 1–7 The eternal circle.

However, at this time in the telecommunications industry, we can state the following:

  • Within the optical network (the backbone or core network) the bottleneck is the "CPU," because its electrical-based architecture (in switches, routers, and bridges) cannot handle a large number of connected optical fiber WDM links that operate in the terabit range. Thus, the creation of all-optical photonic switches (PXCs) is a high priority in the industry.

  • At the edge of the network, and to the end user, the bottleneck is the "bandwidth," but not because of the optical fiber. The bottleneck is due to the continued use of the telephone-based copper plant, and the mobile phone links (and the very slow process of getting it upgraded).

  • The "applications" part of the Eternal Circle is a question mark to some people. If the network operators finally provide the bandwidth all the way to the mass market (the residence), will sophisticated three-dimensional, voice/video/data applications be developed to take advantage of the increased capacity? I believe the answer is a resounding yes, assuming the network operators can keep the price affordable to most households.

Expansion of Network Capacity

One of the more interesting changes occurring in the long-distance carrier industry in the United States is the extraordinary growth of bandwidth capacity. This growth is occurring due to the maturation of the WDM technology, and its wide-scale deployment. It is also occurring due to the aggressive deployment of fiber networks by the "non-traditional" carriers; that is, those carriers who have come into the industry in the last few years.

Figure 1–8 shows the growth of long-distance capacity since 1996, and projections through 2001. The shaded bars show total mileage, and the white bars show total capacity, in terabits per second.

Figure 1–8 Long-distance growth in the United States.

Some people question if this bandwidth will be used. Others see it as an opportunity to discount excess capacity, at the expense of the traditional carriers, who are enjoying healthy profits from their long-distance revenues. It will be interesting to see how the scenarios develop over the next few years. Some marketing forecasts state that this situation will lead to a "fire sale" of DS1 and DS3 lines.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020