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rates at 40 Gbps — and ultimately at 1 Tbps — this DWDM infrastructure enables seamless access to bandwidth-intensive multimedia applications. Capabilities of optical network elements such as optical add-and-drop multiplexers (OADMs) in provisioning transparent optical transmission functions and network management services are also examined. 3.25 UNDERSEA OPTICAL NETWORK SOLUTIONS Spiraling demand for high-capacity networks to support multimedia services and applications contributes to deployment of undersea optical networks. Initially imple- mented in the mid-1990s, undersea optical networks originally employed SONET/SDH infrastructures. Present-day undersea initiatives typically employ WDM and DWDM technologies for enabling oceanic transmissions at multigigabit and multiterabit rates over long distances. Representative initiatives in the underwa- ter optical network domain are now explored. 3.25.1 ALCATEL 3.25.1.1 SEA-ME-WE 3 Alcatel provisions network management operations for undersea network configu- rations such as SEA-ME-WE 3. Featuring ATM-over-WDM and SDH-over-WDM technologies, the SEA-ME-WE 3 configuration upon completion will extend over 38,000 kilometers and feature 40 landing points in 34 countries between the Euro- pean Union and Asia. Transmission rates ranging from 2.488 Gbps to 50 Gbps over two pairs of undersea fiber optic cabling will be enabled. Each optical fiber strand supports eight wavelengths or fiber optic channels. Each wavelength or channel supports multimedia transmission at 2.488 Gbps (OC-48 or STM-16). Network segments between Hong Kong and Korea are currently in operation. 3.25.2 AT&T AT&T employs WDM technology to provide communications services via a trans- Atlantic fiber optic ring network to landing points in the United States, Great Britain, and France. This undersea network also utilizes forward error correction (FEC) control mechanisms for enabling reliable transmission of multimedia applications at 10 Gbps. Infrastructure upgrades supporting transmission rates at 20 Gbps are in development. 3.25.3 FLAG (FIBER OPTIC LINK AROUND THE GLOBE) TELECOM FLAG (Fiber Optic Link Around the Globe) Telecom operates underwater networks that support SDH-over-DWDM technologies and administers network landing points in Italy, Egypt, Spain, Jordan, the United Arab Emirates, Saudi Arabia, Malaysia, India, Korea, Thailand, and China. FLAG Telecom gateways situated in Eastern Africa, the Asia-Pacific region, the United Kingdom, South America, the Middle East, Latin America, the European Union, and the United States are designed to enable worldwide connectivity. FLAG Telecom also supports interconnections of 0889Ch03Frame Page 143 Wednesday, April 17, 2002 3:04 PM © 2002 by CRC Press LLC undersea networks to terrestrial broadband networks such as the FLAG Europe-Asia fiber optic network and the GTS Trans-European DWDM Network. FLAG Telecom buries optical fiber cable below the seabed to eliminate disrup- tion to undersea habitats and to safeguard undersea networks from damage caused by strong harbor currents, adverse weather conditions, electromagnetic interference, and disruptions associated with congested shipping lanes. The FLAG Telecom under- sea fiber optic system supports rates at 2.488 Gbps (OC-48 or STM-16) for enabling high-speed multimedia transmission, fully protected voice services, and Internet broad- casts. Upon completion, the FLAG undersea DWDM network will interlink landing points in the United Kingdom and Japan via the Pacific Ocean, the South China Sea, the Indian Ocean, the Red Sea, the Mediterranean Sea, and the Atlantic Ocean. 3.25.3.1 FA-1 (Flag Atlantic-1) Trans-Atlantic Network As with other FLAG undersea initiatives, the FA-1 (Flag Atlantic-1) Trans-Atlantic Network employs laser-generated lightwaves for transmitting digital information via WDM and DWDM technologies. The FA-1 Trans-Atlantic Network features a dual terrestrial and undersea optical fiber infrastructure for interconnecting landing points in the United States, the European Union, the Asia-Pacific region, and the Middle East. In addition, the FA-1 Trans-Atlantic Network provisions 5 Tbps of total raw capacity and supports secure digital transmissions via an SDH-over-DWDM back- bone network at rates reaching 2.5 Tbps. 3.25.3.2 FL-A1 (FLAG ASIA) Segment Currently in development by FLAG Telecom, the FL-A1 (Flag Asia) segment is an undersea DWDM network that provisions services for international communications carriers. GTS expects to lease protected capacity on FL-A1 for enabling seamless connections at 400 Gbps and unprotected capacity at 800 Gbps in an area that extends from landing points in New York to the GTS Trans-European DWDM Network. 3.25.4 FRANCE TELECOM France Telecom employs an SDH-over-WDM optical infrastructure for fiber optic undersea networks that support high-speed, full-duplex voice, video, and data trans- mission, and provision on-demand bandwidth. France Telecom participates in the Americas II and Atlantis-2 undersea fiber optic initiatives. 3.25.4.1 Americas II Undersea Network The Americas II fiber optic undersea network links North America, South America, and the Caribbean region in a WDM configuration that extends over 8,000 kilometers. This system features four pairs of fiber optic cabling and a landing point in Martinique. Information transport at 40 Gbps is supported. 3.25.4.2 Atlantis-2 Undersea Network The Atlantis-2 WDM undersea fiber optic network fosters interconnections between landing points in Portugal, the Canary Islands, the Cape Verde Islands, Senegal, 0889Ch03Frame Page 144 Wednesday, April 17, 2002 3:04 PM © 2002 by CRC Press LLC Brazil, and Argentina. This configuration employs two pairs of fiber optic cabling. Each fiber optic strand supports rates ranging between 5 Gbps and 20 Gbps. The network extends to 12,000 kilometers. 3.25.5 GLOBAL CROSSING 3.25.5.1 Atlantic Crossing 1 (AC-1) and Atlantic Crossing 2 (AC-2) Undersea Networks Sponsored by Global Crossing, the Atlantic Crossing 1 (AC-1) trans-Atlantic DWDM undersea fiber optic network links landing points in Germany, the Nether- lands, the United Kingdom, and New York City in a fiber optic configuration extending to 14,000 kilometers. In a related initiative, Global Crossing also supports a 2.5 Tbps DWDM undersea network configuration called Atlantic Crossing 2 (AC- 2). The AC-2 undersea network interoperates with the AC-1 installation. 3.25.5.2 Mid-Atlantic Crossing and Pan American Crossing Undersea Networks Developed by Global Crossing, the Mid-Atlantic Crossing undersea fiber optic network interconnects landing points in the Caribbean region and the Eastern United States in a WDM configuration that extends to 7,500 kilometers. Also a Global Crossing project, the Pan American Crossing undersea WDM fiber optic network interconnects landing points in the Caribbean region, Central America, Mexico, and the Western United States in a configuration covering 8,900 kilometers. 3.25.5.3 Global Crossing Undersea Fiber Optic Network in Japan In Japan, Global Crossing supports implementation of a high-speed undersea fiber optic network equipped with DWDM technology that interlinks landing points in Tokyo, Nagoya, and Osaka in a configuration that extends to 1,200 kilometers. 3.25.6 IAXIS Iaxis supports construction of a 10,000-kilometer WDM network in the Mediterra- nean Sea that interlinks landing points in Africa, the European Union, and the Asia- Pacific region. 3.25.7 SOUTH ATLANTIC TELEPHONE/WESTERN CABLE/SOUTHERN AFRICA F AR EAST, PHASE 3 (SAT-3/WASC/SAFE) Currently in development, SAT-3/WASC/SAFE is an undersea fiber optic network that accommodates Africa’s expanding telecommunications requirements. SAT- 3/WASC segments support connections between landing points at sites in Senegal, Portugal, the Ivory Coast, Ghana, Nigeria, and Angola. A WDM Optical Layer enables transmission rates at 20 Gbps, with upgrades to 40 Gbps available. SAFE segments interlink landing points in South Africa, Mauritius, and Malaysia. 0889Ch03Frame Page 145 Wednesday, April 17, 2002 3:04 PM © 2002 by CRC Press LLC As with other undersea networks, SAT-3/WASC/SAFE implementation involves mapping the topography of the ocean bed with sonar prior to fiber optic installation. Aluminum sheaths protect optical fiber from shark bites. These sheaths are situated between depths of 1,000 meters and 3,000 meters. Moreover, fiber optic cabling at shallower depths is also encased in aluminum sheaths to prevent damage from rocks, fishing nets, and anchors. A satellite remote control and surveillance system for SAT- 3/WASC/SAFE aids in the identification of network faults. Upon completion, this network will support transmission over a maximum of eight fiber optic pairs for enabling a total rate of 80 Gbps. 3.25.8 TELECOM NEW ZEALAND, OPTUS, SOUTHERN CROSS CABLES, AND W ORLDCOM 3.25.8.1 Trans-Pacific Southern Cross Network Telecom New Zealand, Optus, Southern Cross Cables, and WorldCom sponsor the Trans-Pacific Southern Cross Network. Presently in development, this self-restoring, undersea fiber optic, long-haul configuration interlinks landing points in Australia, New Zealand, Fiji, Hawaii, and the West Coast of the United States in a terrestrial and undersea fiber optic network configuration. A high-speed, high-capacity config- uration, the Trans-Pacific Southern Cross Network employs SONET/SDH-over- WDM/DWDM technologies for provisioning an initial capacity of 40 Gbps on each fiber optic pair. Upon completion, the Trans-Pacific Southern Cross Network will enable transmission rates reaching 480 Gbps and transport high-quality, high-per- formance voice, video, and data signals in an area of coverage that extends to 30,500 kilometers. 3.26 SUMMARY The spiraling increase in the volume of information traffic transmitted across com- munications networks contributes to the development of terrestrial and undersea optical fiber network solutions for provisioning additional network capacity. The communications capacity of fiber optic cabling is immense. According to the NSF (National Science Foundation), a single strand of optical fiber possesses an accessible bandwidth approaching 100,000 Gigahertz (GHz). By comparison, the entire radio spectrum managed by the Federal Communications Commission (FCC) for enabling FM and AM radio and television programming, cellular telephony, and satellite services consists of approximately 60 GHz. In this chapter, representative SONET/SDH solutions in enabling dependable and reliable voice, video, data, and still-image transmission, and rapid access to bandwidth-intensive applications are described. Capabilities of SONET/SDH imple- mentations in fostering reliable tele-education and telemedicine programs, telecol- laborative research, and E-government activities are examined. Optical networks are evolving at a remarkable pace. Unprecedented demand for high-speed, high-capacity optical solutions contributes to the popularity of optical fiber networks that employ third-generation WDM and DWDM optical technologies 0889Ch03Frame Page 146 Wednesday, April 17, 2002 3:04 PM © 2002 by CRC Press LLC and the emergence of optical network configurations such as PONs, SuperPONs, APONs, and AONs. Distinguishing characteristics of these optical network config- urations are highlighted. Distinctive attributes of WDM and DWDM technologies, architectures, compo- nents, and solutions are introduced. The role of WDM and DWDM technologies in contributing to the development of a new Optical Layer that serves as a Sublayer of the Physical Layer or Layer 1 of the OSI (Open Systems Interconnection) Ref- erence Model is highlighted. Network services provided by third-generation WDM and DWDM technologies in supporting extendible, reliable, and dependable next- generation network configurations and provisioning access to bandwidth-intensive multimedia applications with differentiated QoS guarantees in the educational, cor- porate, medical, and governmental sectors are reviewed. Representative examples of terrestrial and undersea WDM and DWDM configurations in supporting ultrafast information transport and providing unprecedented bandwidth for next-generation Internet innovations and services are also examined. 3.27 SELECTED WEB SITES Advanced Research and Development Network Operations Center (ARDNOC). CA*net3 Optical Internet Backbone. Last modified on April 23, 2001. Available: http://www.canet3.net/optical/optical.html Advanced Technology Demonstration Network. ATDNet. Last modified on August 8, 2001. Available: http://www.atd.net/ Alcatel. Submarine Networks. Available: http://www.alcatel.com/submarine/ All-Optical Networking Consortium. Homepage. Last modified on July 30, 1997. Available: http://www.ll.mit.edu/aon/index.html Canadian Network for the Advancement of Research, Industry, and Education (CANARIE). CA*net3. Last modified on September 25, 2001. Available: http://www.canarie.ca/advnet/canet3.html European Commission. The ACTS Information Window. Available: http://www.de.infowin.org/ FLAG (Fiber Optic Link Around the Globe) Telecom. Overview. Available: http://www.flag.bm/index_e1.htm France Telecom. Welcome to France Telecom’s Marine Activities Website. Available: http://www.marine.francetelecom.fr/english/home.htm Global Crossing. The Expanding Network. Available: http://www.globalcrossing.com/network.html?bc = Network High-Speed Connectivity Consortium (HSCC). Home Page. Last modified on July 12, 2001. Available: http://www.hscc.net/ LightReading: The Global Site for Optical Networking. Available: http://www.lightreading.com/ 0889Ch03Frame Page 147 Wednesday, April 17, 2002 3:04 PM © 2002 by CRC Press LLC Massachusetts Institute of Technology Lincoln Laboratory Advanced Networks Group. BoSSNET (Boston-South Network). Available: http://www.ll.mit.edu/AdvancedNetworks/bossnet.html Metropolitan Research and Education Network. MREN: Advanced networking for advanced applications. Last modified on February 21, 2001. Available: http://www.mren.org/ Optical Domain Service Interconnect Coalition. Available: http://www.odsicoalition.com/index.asp PennWell Corporation. LIGHTWAVE. Fiber Optic Communications, Bandwidth Access, and Telecommunications. Available: http://lw.pennwellnet.com/home.cfm Wisconsin Bureau of Network Services. BadgerNet Overview. Last modified on August 20, 2001. Available: http://www.doa.state.wi.us/dtm/bns/overview/history.htm University Corporation for Advanced Internet Development (UCAID). About Abilene. Available: http://www.ucaid.edu/abilene/html/about.html U.S. Department of Defense Advanced Research Projects Agency (DARPA) Information Technology Office (ITO). Next-Generation Internet (NGI). Project List. Available: http://www.arpa.mil/ito/research/ngi/projlist.html U.S. Department of Defense Advanced Research Projects Agency (DARPA) Information Technology Office (ITO). Next-Generation Internet (NGI). SuperNet Testbed. Available: http://www.arpa.mil/ito/research/ngi/supernet.html 0889Ch03Frame Page 148 Wednesday, April 17, 2002 3:04 PM © 2002 by CRC Press LLC 4 Ethernet Networks 4.1 INTRODUCTION The popularity of Web entertainment, E-commerce, and distance learning, and the concurrent demand for ready access to Web applications in the local networking environment, contribute to the widespread implementation of Ethernet communica- tions networks. A flexible, reliable, scalable, and dependable technology, the Ethernet technology suite sustains intranet, extranet, and Internet connectivity in LAN (Local Area Network) environments and interoperates with wireline and wireless solutions. The Ethernet technology suite is defined by a series of specifications and sup- plements associated with the IEEE (Institute of Electrical and Electronics Engineers) 802.3 family of LAN standards. An Ethernet LAN supports operations in a delimited geographic area such as a classroom, a multistory office building, a factory, or a cluster of buildings on a university campus, and enables information exchange and shared workgroup applications over a common communications medium. The mul- tiservice Ethernet platform interworks with technologies that include Frame Relay (FR), FDDI (Fiber Data Distributed Interface), Fibre Channel (FC), DSL (Digital Subscriber Line), cable modem, WDM (Wavelength Division Multiplexing), and DWDM (Dense WDM). A conventional, in-place, 10 Mbps (Megabits per second) Ethernet platform can be readily upgraded to Fast Ethernet, Gigabit Ethernet, and ultimately 10 Gigabit (Gigabits per second or Gbps) Ethernet. As a result, institutions and organizations with in-place 10 Mbps Ethernet implementations that migrate to faster and more powerful Ethernet solutions preserve their investments in Ethernet equipment while gaining additional bandwidth capacity and infrastructure services. A ubiquitous LAN solution, Ethernet is the technology of choice for local network implementations in schools, colleges, universities, libraries, research cen- ters, scientific organizations, government agencies, corporations, and hospitals. As noted in Chapter 3, Ethernet is also an enabler of high-performance high-capacity metropolitan optical network solutions. (See Figure 4.1.) 4.2 PURPOSE Demand for scalable, reliable, dependable, and affordable networks in all types of environments contributes to Ethernet’s dominance in the LAN (Local Area Network) arena. This chapter provides an introduction to the distinctive attributes of Ethernet, Fast Ethernet. Gigabit Ethernet, and 10 Gigabit Ethernet technical solutions. Rep- resentative initiatives supported by the four Ethernets in tele-education, E-government 0889Ch04Frame Page 149 Wednesday, April 17, 2002 3:03 PM © 2002 by CRC Press LLC (electronic government), telehealthcare, and E-business (electronic business) envi- ronments are highlighted. In addition, capabilities of the Ethernet technology suite in enabling shared use of network resources and VPN (Virtual Private Network) implementations, advanced applications and Class of Service (CoS) assurances, and home phoneline network solutions are described. 4.3 FOUNDATIONS Robert Metcalf, then affiliated with the Xerox Palo Alto Research Center, is credited with originally demonstrating Ethernet capabilities in 1973. The term “Ethernet” was the name of the initial LAN product developed by Digital Equipment Corpo- ration (DEC), Intel, and Xerox (DIX) that Metcalf used. The word “Ether” referred to the wireline cabling that was employed. With the sponsorship of DIX, 10 Mbps Ethernet was adopted as the foundation for the IEEE 802.3 LAN standard in 1984. In 1995, Fast Ethernet was adopted as an extension to the Ethernet specification and officially called the IEEE 802.3u standard. Fast Ethernet sustains data transmis- sion via twisted copper pair, coaxial cable, and optical fiber in the local area at rates reaching 100 Mbps. The inability of Fast Ethernet to effectively handle the expanding volume of traffic carried by the LAN backbone and the ongoing need for increased capacity contributed to the emergence and standardization of Gigabit Ethernet. The Gigabit Ethernet standard facilitates transmission rates at 1000 Mbps or 1 Gbps. Gigabit Ethernet retains many of the same features as Ethernet and Fast Ethernet and therefore interworks with the already installed base of Ethernet and Fast Ethernet networks in diverse communications environments. A recent Ethernet innovation, 10 Gigabit Ethernet offers substantial performance enhancements in comparison to its Ethernet predecessors. The four Ethernets support operations, applications, and topologies that follow traditional Ethernet guidelines. Regardless of rates enabled, Ethernet networks FIGURE 4.1 An Ethernet/Fast Ethernet LAN configuration with multiple access points for enabling remote connections via dial-up service, the Internet, and WAN links. Local Server Ethernet Segment Switch Remote Node Remote Node 10Base-T Hubs 100 Mbps 10 Mbps WAN Internet Router Segment 1 Segment 2 Segment 3 0889Ch04Frame Page 150 Wednesday, April 17, 2002 3:03 PM © 2002 by CRC Press LLC effectively transmit traffic in localized environments. In addition, Ethernet config- urations work in concert with other protocols, technologies, and network architec- tures in supporting sophisticated levels of service and complex voice, video, and data applications that feature Class of Service (CoS) assurances. 4.4 ETHERNET TECHNICAL BASICS In the present-day environment, the IEEE 802.3 specification and its Annexes describe a suite of Ethernet systems that are capable of running at speeds of 10 Mbps, 100 Mbps, 1000 Mbps or 1 Gbps, and 10000 Mbps or 10 Gbps via diverse media. Ethernet technology is widely employed in present-day corporate, medical, academic, and home networking environments. In wireline configurations, Ethernet technologies transmit information via optical fiber, coaxial cable, and twisted copper pair or the same cabling used for the Public Switched Telephone Network (PSTN). Ethernet is also a popular enabler of hybrid wireline and wireless configurations employing satellite and microwave technolo- gies. The capabilities of wireless Ethernet configurations are examined in Chapter 9. 4.4.1 E THERNET F RAME F ORMAT According to the IEEE 802.3 LAN standard, the Ethernet frame is the basic unit of transport in an Ethernet network. This frame functions as an envelope for carrying data through the networking configuration. The Ethernet frame consists of several different fields. The frame begins with an eight-byte preamble for synchronizing operations and alerting the Ethernet NIC (Network Interface Card) to accept incoming data. The frame next features a six- byte destination address field, six-byte source address field, a two-byte type field, and a data field that contains a maximum of 1500 bytes. The Ethernet frame concludes with a four-byte frame check sequence field for verifying data integrity. Ethernet frames vary in length and size from 64-byte packets to 1514-byte packets. The Ethernet frame format is used consistently across Ethernet, Fast Ethernet, Gigabit Ethernet, and 10 Gigabit Ethernet platforms. 4.4.2 C ARRIER S ENSE M ULTIPLE A CCESS WITH C OLLISION D ETECTION (CSMA/CD) P ROTOCOL The Ethernet LAN specification describes a contention Media Access Control (MAC) protocol called Carrier Sense Multiple Access with Collision Detection (CSMA/CD). The CSMA/CD protocol defines the process by which the network allocates trans- mission rights among network stations or nodes that share a common media. In the present-day environment, CSMA/CD is a commonly used protocol in Ethernet networks with bus, tree, and star topologies. In moving forward with the Carrier Sense Multiple Access (CSMA) process, a network station or node seeking to transmit a packet first listens to the Ethernet medium in order to sense if the medium is busy. The Multiple Access process ensures that every network station is linked to the shared communications medium. In the 0889Ch04Frame Page 151 Wednesday, April 17, 2002 3:03 PM © 2002 by CRC Press LLC absence of signaling on the Ethernet medium, any network station can initiate the transmission process. Conversely, if a signal is detected, a network station withholds transmission until the medium is idle. Collisions occur when two or more network stations simultaneously initiate transmissions upon sensing a clear channel. Upon detecting a collision, the trans- mitting stations execute an algorithm that supports a back-off procedure. These network stations then wait until the medium is clear prior to initiating the retrans- mission process. In an Ethernet network, packet delivery is not guaranteed. As a consequence, Ethernet transport of packets to destination network nodes is catego- rized as “best-effort delivery” or “ordered chaos.” An Ethernet local network is also known as a CSMA/CD LAN. CSMA/CD originated with the implementation of the Aloha protocol in the Aloha radio network in the late 1960s. The Aloha protocol is a random access control method that led to the development of CSMA/CA (Carrier Sense Multiple Access/Collision Access) and subsequently to CSMA/CD. With CSMA/CA, information transmission occurs whenever a network station has a frame or information packet to transmit. If a frame does not reach its desti- nation, the frame is re-transmitted after a random period of time. If two frames collide, the data encapsulated in both frames are damaged or lost. The slotted Aloha version of the Aloha protocol minimizes the number of network collisions by assign- ing timeslots for each frame or packet to be transported. Developed by the University of Hawaii and the U.S. Department of Defense Advanced Research Projects Agency (DARPA), the Aloha radio network was a contention system that featured a shared channel, supported satellite transmissions, and enabled information transport in networks with ring topologies. 4.4.2.1 IEEE 802.3 CSMA/CD Working Group of the IEEE LAN and MAN Standards Committee The IEEE 802.3 Working Group of the IEEE LAN (Local Area Network) and MAN (Metropolitan Area Network) Standards Committee defines CSMA/CD specifica- tions for Ethernet installations. This Working Group also coordinates standards activities with the Fast Ethernet Alliance and the Gigabit Ethernet Alliance now known as the I0 Gigabit Ethernet Alliance (I0GEA). Vendors, computer manufac- turers, and network providers that promote the publication and adoption of IEEE 802.3 Ethernet standards typically participate in the Fast Ethernet Alliance and the Gigabit Ethernet Alliance 4.5 TECHNICAL FUNDAMENTALS Regardless of the speed supported, a typical Ethernet system consists of physical components that include network stations or network nodes; internetworking devices such as hubs, bridges, routers, and switches for interlinking network segments; repeaters for regenerating Ethernet signals; and NICs (Network Interface Cards). Network stations or nodes are linked to an Ethernet network with an Ethernet adapter or interface. This adapter performs MAC (Media Access Control) functions for 0889Ch04Frame Page 152 Wednesday, April 17, 2002 3:03 PM © 2002 by CRC Press LLC [...]... MultiProtocol-over-ATM Working Group clarifies MPOA operations 4. 8.3.2 Routing Information Protocol (RIP) The ATM Forum endorses the Routing Information Protocol (RIP) This protocol establishes links between ATM subnetworks and Ethernet and Fast Ethernet networks to support fast and dependable IP services 4. 8 .4 4.8 .4. 1 FAST ETHERNET COMPETITOR TECHNOLOGIES 100VG-AnyLAN 4. 8 .4. 1.1 100VG-AnyLAN Transmission The 100VG-AnyLAN... including T-1 networks for extending broadband metropolitan (metro) services to commercial buildings and SOHO (Small Office/Home Office) venues Extreme Networks also supports an Ethernet-over-T-1 installation that employs multilink, point-to-point connections for enabling multiple channel consolidation and supporting transmissions ranging from 1. 544 Mbps (T-1) to 6 Mbps in wider area installations 4. 6.5 10... installations 4. 6 .4. 1 3Com Solutions 3Com supports a Visitor and Community Network (VCN) System for provisioning 10 Mbps Ethernet services in condominiums, small- and medium-sized business establishments, hotels, and office buildings This VCN solution enables video-ondemand (VOD), high-speed, always-on Internet connections for Web browsing, and IP telephony 4. 6 .4. 2 Extreme Networks Extreme Networks provisions... 100BASE-T4, 100BASETX, and 100BASE-FX 4. 7.2 4. 7.2.1 FAST ETHERNET TRANSMISSION METHODS 100BASE-T 100BASE-T or Fast Ethernet employs four pairs of UTP (Unshielded Twisted Pair) Categories 3, 4, or 5 copper wires to facilitate baseband operations and transmissions at 100 Mbps over network segments that extend to 100 meters 100BASE-T subcategories include 100BASE-T2, 100BASE-T4, and 100BASE-TX 4. 7.2.1.1... supported © 2002 by CRC Press LLC 0889Ch04Frame Page 158 Wednesday, April 17, 2002 3:03 PM 4. 6.3.5 10BROAD-36 10BROAD-36 supports broadband Ethernet transmissions at rates of 10 Mbps via coaxial cable network segments that extend to 3,600 meters 4. 6 .4 10 MBPS ETHERNET MARKETPLACE 10 Mbps Ethernet interoperates with diverse technologies Vendors such as 3Com and Extreme Networks support Ethernet-over-VDSL... 0889Ch04Frame Page 171 Wednesday, April 17, 2002 3:03 PM 4. 14 4. 14. 1 ETHERNET VLANS (VIRTUAL LANS) VLAN CAPABILITIES Ethernet, Fast Ethernet, and Gigabit Ethernet switches enhance network performance and security and facilitate access to bandwidth-intensive multimedia applications These devices also enable network segmentation to support development and implementation of VLANs (Virtual Local Area Networks) ... Figure 4. 4.) 4. 8 4. 8.1 FAST ETHERNET STANDARDS ORGANIZATIONS AND ACTIVITIES FAST ETHERNET ALLIANCE The Fast Ethernet Alliance promotes development of Fast Ethernet solutions that are compatible with the CSMA/CD protocol endorsed in the original Ethernet specification This Alliance also supports the implementation of interoperable Ethernet and Fast Ethernet products such as 10/100 Ethernet switches 4. 8.2... (SLANs) 4. 6.3 .4 10BASE-F The letter “F” in 10BASE-F Ethernet specifications signifies fiber optic cabling 10BASE-F implementations support baseband transmission rates at 10 Mbps and employ optical fiber cabling to facilitate in -building point-to-point connections and SLAN (switched LAN) solutions Ethernet-over-fiber optic configurations employ 10BASE-FL, 10BASE-FP, and 10BASE-FP technologies 4. 6.3 .4. 1 10BASE-FL... 100VG-AnyLAN, Fast Ethernet dominates the present-day marketplace 4. 8 .4. 2 Fiber Data Distributed Interface (FDDI) 4. 8 .4. 2.1 FDDI Capabilities Initially standardized in the ANSI (American National Standards Institute) X3T9.5 specification released in 1989, the international FDDI specification is also known as ISO (International Standards Organization) 93 14 FDDI supports transmissions via fiber optic cabling In addition,... bridges, and switches foster FDDI interoperability with star and bus LAN topologies In addition, FDDI serves as a fiber optic backbone for LAN installations 4. 8 .4. 2.2 FDDI Transmission The maximum frame size supported by FDDI includes 45 00 bytes, with 44 78 bytes allocated for the payload or information field The remaining bytes, including a header field and a trailer field, ensure dependable information delivery . subnetworks and Ethernet and Fast Ethernet networks to support fast and dependable IP services. 4. 8 .4 FAST ETHERNET COMPETITOR TECHNOLOGIES 4. 8 .4. 1 100VG-AnyLAN 4. 8 .4. 1.1 100VG-AnyLAN Transmission The. http://www.arpa.mil/ito/research/ngi/supernet.html 0889Ch03Frame Page 148 Wednesday, April 17, 2002 3: 04 PM © 2002 by CRC Press LLC 4 Ethernet Networks 4. 1 INTRODUCTION The popularity of Web entertainment,. and office buildings. This VCN solution enables video-on- demand (VOD), high-speed, always-on Internet connections for Web browsing, and IP telephony. 4. 6 .4. 2 Extreme Networks Extreme Networks

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