While many new technologies might be considered in this review of new telecommunications technologies, this paper will be restricted to a consideration of those likely to have a major impact on corporate networks and communications.
OPTICAL NETWORKS, ATM TECHNOLOGY AND GIGABIT ETHERNET PRIVATE NETWORKS
Optical Networks
A small band of researchers expect that optical fiber amplifiers will revolutionize communications. Optical amplifiers and optical switches are now being installed in many networks, providing an opportunity to utilize the latent fiber bandwidth and provide an enormous increase in backbone capacity. All-optical, or lightwave-to-lightwave networks will become a reality in the near future. The need to transmit using lightwaves over fiber optic backbones and convert lightwaves to electrical signals for switching and transfers to end points in the network will soon become a thing of the past.
OPTICAL NETWORKS, ATM TECHNOLOGY AND GIGABIT ETHERNET PRIVATE NETWORKS
Optical Networks
A small band of researchers expect that optical fiber amplifiers will revolutionize communications. Optical amplifiers and optical switches are now being installed in many networks, providing an opportunity to utilize the latent fiber bandwidth and provide an enormous increase in backbone capacity. All-optical, or lightwave-to-lightwave networks will become a reality in the near future. The need to transmit using lightwaves over fiber optic backbones and convert lightwaves to electrical signals for switching and transfers to end points in the network will soon become a thing of the past.
Today, major communications networks are already using substantial lightwave devices in their high-speed networks. The managers of these networks foresee the day in the not distant future when network links will go "lightwave to lightwave" without much conversion to other forms. In addition, these networks can use new compression and modulation technologies to add more capacity to their fiber optic backbones, raising capacity by a factor of nearly ten over the next few years.
As a consequence, telephone companies are likely to offer large corporations substantially greater speed connections to their networks, with 2.4 gigabits per second being the most likely. In addition, the price of such connections, now $200,000 per month or more, will probably decline to about $10,000 by early in the next decade, a twenty-fold decline in price over just four or five years. Such a change would certainly be revolutionary. It could also herald a shift in network connection devices from electronic to lightwave, making communications even cheaper and less complex.
The main issue these carriers face in the coming years is how costly it will be to divide high-speed drops into links that bring communications to phones and desktops. At present, this conversion in office buildings is likely to be quite expensive, slowing the economic impact of the advantages of lightwave technology. If rapid technological innovation takes place in this arena, it could accelerate the creation of very inexpensive broadband services, first to businesses and later to consumers.
Asynchronous Transfer Mode (ATM) Technology
Prior to the recent interest in optical networks, Asynchronous Transfer Mode (ATM) technology was considered to be the major technology that would shape the future of communications. Many long distance firms, including AT&T, Sprint, and MCI, plus Internet Service Providers UUNet and PSINet, have adopted ATM technology for high speed communications that can offer direct access to customers. The advent of optical networks, plus competition from Gigabit Ethernet and less expensive frame relay services, may result in ATM losing out as a viable technology. Many vendors of ATM equipment have begun to shift to optical switching technologies.
ATM, when first proposed, seemed to be a remedy for many communications problems. It could alleviate bottlenecks at the desktop and deliver vast amounts of information across long distances. ATM is a switched, connection-oriented technology with a fixed cell size, making it an inherently reliable, scaleable technology that can speed data from one desktop to another or across national networks. The Achilles heel of ATM has been the high cost of its deployment and the slow speed it brings to the desktop, only twenty-five Megabits per second (Mb/s) at a time when Gigabit Ethernet will soon offer users 1000 Mb/s. This has retarded its deployment.
Nevertheless, due to its high 155 Mb/s speed, many corporate network backbones have adopted ATM technology. In addition, long-distance phone companies have favored using the technology, with some using it at 622 Mb/s. These networks have responded to the immediate demand for speed that users needed.
Now, the future of ATM seems more unpredictable. In some environments, such as corporate networks, it may continue a rapid pace of deployment. In national long-distance networks, ATM no longer seems to be the technology of choice, given the significant advantages of optical switched networks.
Gigabit Ethernet
Gigabit Ethernet will relieve congestion problems in communications networks used for corporate data, Local Area Networks (LANs). The bottlenecks are present because the speed of external network connections and desktops has increased dramatically, but the ability to send complex graphics documents and use videoconferencing in LANs has not improved at complementary speed. Thus, there is a growing speed bottleneck in data networks.
Gigabit Ethernet is a new standard that will let corporate network users send packets of data at 1,000 Megabits per second (Mb/s) through campus networks. These networks originally functioned using the Ethernet standard at ten Mb/s. The new standard, which should be official in March 1998, builds on the Fiber Channel, which offers 800 Mb/s throughput that can be accelerated by boosting the signaling rate to 1.25 Gigabits per second (Gb/s). Commercial Gigabit Ethernet products are likely to be adopted in large numbers in 1999.
As a consequence, telephone companies are likely to offer large corporations substantially greater speed connections to their networks, with 2.4 gigabits per second being the most likely. In addition, the price of such connections, now $200,000 per month or more, will probably decline to about $10,000 by early in the next decade, a twenty-fold decline in price over just four or five years. Such a change would certainly be revolutionary. It could also herald a shift in network connection devices from electronic to lightwave, making communications even cheaper and less complex.
The main issue these carriers face in the coming years is how costly it will be to divide high-speed drops into links that bring communications to phones and desktops. At present, this conversion in office buildings is likely to be quite expensive, slowing the economic impact of the advantages of lightwave technology. If rapid technological innovation takes place in this arena, it could accelerate the creation of very inexpensive broadband services, first to businesses and later to consumers.
Asynchronous Transfer Mode (ATM) Technology
Prior to the recent interest in optical networks, Asynchronous Transfer Mode (ATM) technology was considered to be the major technology that would shape the future of communications. Many long distance firms, including AT&T, Sprint, and MCI, plus Internet Service Providers UUNet and PSINet, have adopted ATM technology for high speed communications that can offer direct access to customers. The advent of optical networks, plus competition from Gigabit Ethernet and less expensive frame relay services, may result in ATM losing out as a viable technology. Many vendors of ATM equipment have begun to shift to optical switching technologies.
ATM, when first proposed, seemed to be a remedy for many communications problems. It could alleviate bottlenecks at the desktop and deliver vast amounts of information across long distances. ATM is a switched, connection-oriented technology with a fixed cell size, making it an inherently reliable, scaleable technology that can speed data from one desktop to another or across national networks. The Achilles heel of ATM has been the high cost of its deployment and the slow speed it brings to the desktop, only twenty-five Megabits per second (Mb/s) at a time when Gigabit Ethernet will soon offer users 1000 Mb/s. This has retarded its deployment.
Nevertheless, due to its high 155 Mb/s speed, many corporate network backbones have adopted ATM technology. In addition, long-distance phone companies have favored using the technology, with some using it at 622 Mb/s. These networks have responded to the immediate demand for speed that users needed.
Now, the future of ATM seems more unpredictable. In some environments, such as corporate networks, it may continue a rapid pace of deployment. In national long-distance networks, ATM no longer seems to be the technology of choice, given the significant advantages of optical switched networks.
Gigabit Ethernet
Gigabit Ethernet will relieve congestion problems in communications networks used for corporate data, Local Area Networks (LANs). The bottlenecks are present because the speed of external network connections and desktops has increased dramatically, but the ability to send complex graphics documents and use videoconferencing in LANs has not improved at complementary speed. Thus, there is a growing speed bottleneck in data networks.
Gigabit Ethernet is a new standard that will let corporate network users send packets of data at 1,000 Megabits per second (Mb/s) through campus networks. These networks originally functioned using the Ethernet standard at ten Mb/s. The new standard, which should be official in March 1998, builds on the Fiber Channel, which offers 800 Mb/s throughput that can be accelerated by boosting the signaling rate to 1.25 Gigabits per second (Gb/s). Commercial Gigabit Ethernet products are likely to be adopted in large numbers in 1999.
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