The International Telecommunication Union (ITU) has put together a framework for 3G mobile communications systems that are capable of bringing high-quality mobile multimedia services to a worldwide mass market based on a set of standardized interfaces.

Known as International Mobile Telecommunications-2000 (IMT-2000), this framework encompasses a small number of frequency bands, available on a globally harmonized basis, that make use of existing national and regional mobile and mobile-satellite frequency allocations.

IMT-2000 is the largest telecommunications project ever attempted, involving regulators, operators, manufacturers, media, and information technology (IT) players from all regions of the world as they attempt to position themselves to serve the needs of an estimated 2 billion mobile users worldwide by 2010.

Originally conceived in the early 1990s when mobile telecommunications provided only voice and low-speed circuit-switched data, the IMT-2000 concept has adapted to the changing telecommunication environment as its development progressed. In particular, the advent of Internet, intranet, e-mail, e-commerce, and video services has significantly raised user expectations of the responsiveness of the network and the terminals and, therefore, the bandwidth of the mobile channel.

Over the years, mobile telecommunications systems have been implemented with great success all over the world. Many are still first-generation systems—analog cellular systems such as the Advanced Mobile Phone System (AMPS), Nordic Mobile Telephone (NMT), and the Total Access Communication System (TACS). Most systems are now in the second generation, which is digital in nature. Examples of digital cellular systems include Global System for Mobile (GSM) communications, Digital AMPS (DAMPS), and Japanese Digital Cellular (JDC).

Although both first- and second-generation systems were designed primarily for speech, they offer low-bit-rate data services as well. However, there is little or no compatibility between the different systems, even within the same generation. The spectrum limitations and various technical deficiencies of second-generation systems and the potential fragmentation problems they could cause in the future led to research on the development and standardization of a global 3G platform.

The ITU and regional standards bodies came up with a “family of systems” concept that would be capable of unifying the various technologies at a higher level to provide users with global roaming and voice-data convergence, leading to enhanced services and support for innovative multimedia applications. The result of this activity is IMT-2000, a modular concept that takes full account of the trends toward convergence of fixed and mobile networks and voice and data services.

The 3G platform represents an evolution and extension of current GSM systems and services available today, optimized for high-speed packet data-rate applications, including highspeed wireless Internet services, videoconferencing, and a host of other data-related applications. Vendor compliance with IMT-2000 enables a number of sophisticated applications to be developed.

For example, a mobile phone with color display screen and integrated 3G communications module becomes a general-purpose communications and computing device for broadband Internet access, voice, videotelephony, and videoconferencing. These applications can be used by mobile professionals on the road, in the office, or at home.

The number of Internet Protocol (IP) networks and applications is growing fast. Most obvious is the Internet, but private IP networks (i.e., intranets and extranets) show similar or even higher rates of growth and usage. With an estimated billion Internet users worldwide expected in 2010, there exists tremendous pentup demand for 3G capabilities.

3G networks will become the most flexible means of broadband access because they allow for mobile, office, and residential use in a wide range of public and nonpublic networks. Such networks can support both IP and non-IP traffic in a variety of transmission modes, including packet (i.e., IP), circuit- switched (i.e., PSTN), and virtual circuit (i.e., ATM).

Goals of IMT-2000

Under the IMT-2000 model, mobile telephony will no longer be based on a range of market-specific products but will be founded on common standardized flexible platforms that will meet the basic needs of major public, private, fixed, and mobile markets around the world. This approach should result in a longer product life cycle for core network and transmission components and offer increased flexibility and cost-effectiveness for network operators, service providers, and manufacturers.

In developing the family of systems that would be capable of meeting the future communications demands of mobile users, the architects of IMT-2000 identified several key issues that would have to be addressed to ensure the success of the third-generation of mobile systems.

High Speed Any new system must be able to support highspeed broadband services, such as fast Internet access or multimedia-type applications. Users will expect to be able to access their favorite services just as easily from their mobile equipment as they can from their wire line equipment.

Flexibility The next generation of integrated systems must be as flexible as possible, supporting new kinds of services such as universal personal numbering and satellite telephony while providing for seamless roaming to and from IMT-2000-compatible terrestrial wireless networks. These and other features will greatly extend the reach of mobile systems, benefiting consumers and operators alike.

Affordability The system must be as affordable as today’s mobile communications services, if not more so. Economies of scale achievable with a single global standard will drive down the price to users.

Compatibility Any new-generation system has to offer an effective evolutionary path for existing networks. While the advent of digital systems in the early 1990s often prompted the shutting down of first-generation analog networks, the enormous investments that have been made in developing the world’s 2G cellular networks over the last decade make a similar scenario for adoption of 3G systems untenable.

Differentiation In coordinating the design of the IMT-2000 framework, the ITU was mindful of the need to preserve a competitive domain for manufacturers to foster incentive and stimulate innovation. Accordingly, the aim of IMT-2000 standards is not to stifle the evolution of better technologies or innovative approaches but to accommodate them.

Spectrum Allocations

The 2500- to 2690-MHz band was identified by the 2000 World Radio Conference (WRC-2000) as candidate spectrum for 3G systems, along with the 806- to 960-MHz and 1710- to 1885-MHz bands. The WRC-2000 results allow countries flexibility in deciding how to implement 3G systems. The conference recognized, however, that in many countries the frequency bands identified for 3G systems might already be in use by equally vital services.

In the United States, the 2500- to 2690-MHz band is currently used by the Instructional Television Fixed Service (ITFS) and the Multipoint Distribution Service (MDS), which are experiencing and are expected to see significant future growth, particularly in the provision of new broadband fixed access to the Internet. Given the ubiquitous nature of ITFS/MDS, the FCC found that sharing of this spectrum for 3G does not appear feasible.

Further, the FCC found that reallocating a portion of the 2500- to 2690-MHz band from incumbent services for new 3G mobile wireless services would raise significant technical and economic difficulties. The 1710- to 1755-MHz band is now used by federal government operations and is scheduled for transfer to the private sector on a mixed-use basis by 2004. The 2110- to 2150-MHz and 2160- to 2165-MHz bands are currently used by the private sector for fixed microwave services.

The FCC identified these bands several years ago for reallocation to emerging technologies. The 1710- to 1850-MHz band would be the preferred choice for 3G services. This would partially harmonize U.S. spectrum allocations with those in use or planned internationally. Harmonization would permit economies of scale and reduce costs in manufacturing equipment, as well as facilitate international roaming.

Parts of the 1710- to 1850-MHz band also could be used to harmonize with 2G GSM systems, which are currently used extensively throughout the world and are expected to transition eventually to 3G systems. Other parts of the 1710- to 1850-MHz band could be paired with the 2110- to 2150-MHz band to achieve partial harmonization with spectrum recently auctioned in Europe and elsewhere for 3G systems.

Although decisions have not yet been finalized on allocating these bands to 3G wireless communications at this writing, it looks as if there is general agreement that this is the direction that will be pursued. In addition, the FCC is committed to making spectrum available for new advanced wireless services in the United States, as is the World Radio Conference at the international level.

Radio Interface Technology

A key ingredient of the IMT-2000 framework is the air interface technology for 3G systems. For the radio interface technology, the ITU considered 15 submissions from organizations and regional bodies around the world. These proposals were examined by special independent evaluation groups, which submitted their final evaluation reports to the ITU in September 1998.

The final selection of key characteristics for the IMT-2000 radio interfaces occurred in March 1999, which led to the development of more detailed ITU specifications for IMT-2000. The decision of the ITU was to provide essentially a single flexible standard with a choice of multiple access methods, which include CDMA, TDMA, and combined TDMA/CDMA— all potentially in combination with Space Division Multiple Access—to meet the many different mobile operational environments around the world.

Although 2G mobile systems involve both TDMAand CDMAtechnologies, very little use is currently being made of SDMA. However, the ITU expects the advent of adaptive antenna technology linked to systems designed to optimize performance in the space dimension to significantly enhance the performance of future systems.

The IMT-2000 key characteristics are organized, for both the terrestrial and satellite components, into the radio frequency (RF) part (front end), where impacts are primarily on the hardware part of the mobile terminal, and the baseband part, largely defined in software. In addition to RF and baseband, the satellite key characteristics also cover the architecture and the system aspects.

According to the ITU, the use of common components for the RF part of the terminals, together with flexible capabilities that are primarily software defined in baseband processing, should provide the mobile terminal functionality to cover the various radio interfaces needed in the twenty-first century as well as provide economies of scale in their production.

U.S. proposals submitted to the ITU for consideration as the radio interface technology in the IMT-2000 framework included wideband versions of CDMA, of which there are three competing standards in North America: wideband cdmaOne, WIMS W-CDMA, and WCDMA/NA. All three have been developed from 2G digital wireless technologies and are evolving to 3G technologies.

Early on,WIMS W-CDMAand WCDMA/NA, however, were merged into a single proposed standard and, along with wideband cdmaOne, were submitted to the ITU for inclusion into its IMT-2000 family-ofsystems concept for globally interconnected and interoperable 3G networks. Also submitted to the ITU was a separate proposal for a TDMA-based radio interface. Eventually, all these proposals were accepted by the ITU and included in the IMT- 2000 family of standards.

IMT-2000 addresses the key needs of the increasingly global economy—specifically, cross-national interoperability, global roaming, high-speed transmission for multimedia applications and Internet access, and customizable personal services. The markets for all of these exist now and will grow by leaps and bounds through the next millenium. IMT-2000 puts into place standards that permit orderly migration from current 2G networks to 3G networks while providing a growth path to accommodate more advanced mobile services.

When it comes to computer networks, the wireless access point from Linksys is the preferred choice of those who want the best wireless broadband connection that is easy to install and configure. It should be understood that a wireless access point or WAP allow other communication devices to connect wirelessly to a network. This would include favorite portable, smart phones, GPS devices or any other device that uses Wi-Fi, Bluetooth or any other related technology. Homes, schools and offices that want to establish a computer network used to rely on routers to create a cable network. While cable networks are still the champion when it comes to speed and efficiency, a wireless network is easy to configure and offers total freedom to any computer network.

They are not cheap wireless routers on the market that can be too slow for demanding Internet user. However, the Linksys wireless access point is designed to be used with a Linksys wireless router or other brands to provide a fast and reliable connection. The quality of the router is equally important as that is where the main connection (also called Ethernet) will be. It is also important to know that a wireless access point may be similar to a wireless router, but both are equally important in establishing a quality home or office.
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Nearby Multipoint Distribution Service (LMDS) is a two-way millimeter microwave technological innovation that operates in the 27- to 31-GHz array. This broadband service permits communications providers to offer a range of substantial-bandwidth solutions to homes and companies, including broadband Internet accessibility.

LMDS offers greater bandwidth capabilities than a predecessor technology called “Multichannel Multipoint Distribution Service” (MMDS) but has a maximum range of only 7.five miles from the carrier’s hub to the customer premises. This assortment can be extended, even so, via the use of optical fiber backlinks.

LMDS offers tremendous bandwidth—enough to support 16,000 voice conversations in addition 200 channels of tv programming. Figure L-two contrasts LMDS with the bandwidth available about other wireless providers. Aggressive Local Trade Carriers (CLECs) can deploy LMDS to entirely bypass the neighborhood loops of the Incumbent Regional Trade Carriers (ILECs), eliminating entry costs and steering clear of services-provisioning delays.

Because the service entails setting up devices in between the provider’s hub spot and client buildings for the microwave hyperlink, LMDS fees far significantly less to deploy than installing new fiber. This makes it possible for CLECs to really economically provide customer traffic onto their present metropolitan fiber networks and, from there, to a nationwide backbone network. The method amid several CLECs is to provide LMDS to entrepreneurs of multitenant workplace buildings and then install cable to each and every tenant who subscribes to the service.

The cabling goes to an on-premises switch, which is operate to the antenna on the building’s roof. That antenna is aimed at the services provider’s antenna at its hub area. The line-of-sight wireless link between the two antennas provides a broadband “pipe” for many voice, data, and video applications. Subscribers can use LMDS for a assortment of high-bandwidth applications, like tv broadcast, videoconferencing, LAN interconnection, broadband Internet accessibility, and telemedicine.

LMDS operation demands a apparent line of sight between the carrier’s hub station antenna and the antenna at each customer place. The highest array between the two is 7.five miles. However, LMDS is also able of running with out getting a direct line-of-sight with the receiver. This characteristic, extremely desirable in created-up urban regions, might be attained by bouncing signals off buildings so that they get close to obstructions.

At the receiving area, the data packets arriving at distinct periods are held in queue for resequencing prior to they are handed to the application. This scheme does not perform effectively for voice, however, because the delay resulting from queuing and resequencing disrupts two-way conversation. At the carrier’s hub location there is a roof-mounted multisectored antenna.

Every single sector of the antenna gets/transmits signals in between by itself and a distinct client place. This antenna is really little, some measuring only 12 inches in diameter. The hub antenna brings the multiplexed visitors down to an indoor switch that processes the info into 53-byte Asynchronous Transfer Mode (ATM) “cells” for transmission above the carrier’s fiber network.

These individually addressed cells are converted back to their native format just before heading off the carrier’s network to their appropriate destinations—the Internet, Public Switched Phone Network (PSTN), or customer’s remote place. At each and every customer’s area, there is a rooftop antenna that sends/receives multiplexed traffic.

This site visitors passes by way of an indoor network interface unit (NIU) that gives the gateway among the RF (radio frequency) elements and the in-creating equipment, this kind of as a LAN hub, Non-public Branch Exchange (PBX), or videoconferencing method. The NIU contains an up/down converter that changes the frequency of the microwave signals to a reduced intermediate frequency (IF) that the electronics in the workplace gear can manipulate much more effortlessly (and inexpensively).

In May 1999, the FCC held the last auction for LMDS spectrum. More than one hundred firms certified for the auctions, bidding versus each and every other for licenses in select basic buying and selling locations (BTAs). The FCC auctioned two sorts of licenses in each industry: An “A-block” license permits the holder to provision 1150 MHz of spectrum for distribution among its customers, even though a “B-block” license permits the holder to provision 150 MHz.

Most of the A-block licenses in the most significant BTAs had been won by key CLECs, while the B-block licenses had been taken by smaller organizations, Internet service providers (ISPs), universities, and authorities companies. The licenses are granted for a 10-year time period, following which the FCC can consider them back again if the holder does not have support up and running.

Improvement Heritage

Bernard Bossard is generally recognized as the inventor of LMDS. Bossard, who had labored with microwaves for the military, believed that he could make stage-to-multipoint video clip work in the 28-GHz band. Not interested in sending substantial-driven, low-frequency signals over long distances, Bossard targeted instead on sending reduced-powered, large-frequency signals above a quick distance. The consequence was LMDS.

In 1986, he received funding and shaped CellularVision with his economic backers. CellularVision then spun off the technical rights to the technological innovation into a separate subsidiary, CT&ampT, that licenses it to other businesses. CellularVision was awarded a pioneer’s choice license by the FCC for its role in building LMDS. CellularVision began running a industrial LMDS in metropolitan New York, offering video clip programming to subscribers in the Brighton Beach location.

In 1998, CellularVision changed its name to SPEEDUS.COM. The organization has a network operations center and recently has been expanding the quantity of running cells in the New York place and now statements a lot more than 12,000 residential and company subscribers. Pace services is delivered by way of 14 completely practical Web broadcast stations in operation under SPEEDUS.COM’s FCC license covering metropolitan New York.

Pace subscribers are ready to browse the Net utilizing the company’s Velocity modem able of downstream speeds of up to 48 Mbps, which is 31 periods more quickly than a complete T1 line. In the SPEEDUS.COM method, cable programming is downlinked from satellites to the company’s head-conclude facility, where local broadcast transmissions are also received. At the company’s grasp handle area, the programming signals are then amplified, sequenced, scrambled, and up-converted to 28 GHz.

The Pace.COM transmitters and repeaters then broadcast a polarized FM signal in the 28-GHz band above a radius of up to three miles to subscribers and to adjacent cells for transmission. A6-inch-square, extremely directional, flat-plate, window- , roof- , or wall-mounted antenna receives the scrambled signal and delivers it to the addressable settop converter, which decodes the signals. The subscriber receives 49 channels of substantial-high quality video and audio programming, including shell out-per-view and premium channels.

Over 100 firms personal licenses for LMDS. XO Communications (previously acknowledged as Nextlink) is a single of the largest single holders of LMDS licenses in the United States, obtaining invested above $ 800 million in this kind of systems, mostly through the acquisition of other firms that held LMDS licenses. XO is a CLEC and is making use of LMDS to feed traffic to its fiber networks. Its technique to building out a city is to install fiber. In places in which that will get as well prolonged or in which permits are too difficult to come by, XO will use, in this buy, LMDS, Digital Subscriber Line (DSL), and ILEC amenities.

Potential Difficulties

A prospective dilemma for LMDS customers is that the signals can be disrupted by hefty rainfall and dense fog—even foliage can block a signal. In metropolitan locations wherever new construction is a simple fact of existence, a line-of-sight transmission route can vanish practically overnight. For these reasons, a lot of details technologies (IT) executives are leery of trusting mission-crucial applications to this wireless engineering.

Service companies downplay this scenario by claiming that LMDS is just 1 regional entry choice and that fiber links are the way to go for mission-vital applications. In fact, some LMDS companies give fiber as a backup in case the microwave back links experience interference. There is controversy in the business about the economics of the stage-to-multipoint architecture of LMDS, with some authorities declaring that the organization design of heading after lowusage customers is essentially flawed and will never justify the services provider’s expense of equipment, set up, and provisioning.

With an overabundance of fiber in the ground and metropolitan location Gigabit Ethernet services coming on the web at a competitive price, the time for LMDS may have arrive and gone. In addition, newer wireless technologies like free-air laser maintain a considerable speed benefit more than LMDS, as does submillimeter transmission in the 60- and 95-GHz bands. Yet another difficulty that has beset LMDS is that the key license holders have gotten caught up in economic problems, some declaring Chapter eleven personal bankruptcy.

These carriers constructed their networks rapidly, incurring enormous financial debt, without having lining up customers fast plenty of. This technique labored effectively as long as the money markets ended up prepared to continue funding these firms. But once the capital markets dried up in 2000, so did the wireless providers’ coffers and their instant prospective customers. The unsure foreseeable future of these financially strapped carriers has discouraged numerous companies from even hoping LMDS.

Fiberoptics is the main transmission medium for broadband connectivity nowadays. Nevertheless, of the estimated four.6 million commercial buildings in the United States, 99 percent are not served by fiber. Businesses are at a aggressive downside in today’s details-intensive earth except if they have accessibility to broadband entry services, such as highspeed Web accessibility.

These businesses, which includes many information-intensive higher-technology organizations, can be served adequately with LMDS. Regardless of the fiscal problems of LMDS companies, the technological innovation has the prospective to turn out to be a important portion of the international accessibility marketplace, which will consist of a combine of many technologies, including DSL, cable modems, broadband satellite, and fiberoptic techniques.

The Maritime, or Marine, Radio Solutions have advanced from the earliest practical makes use of of radio. In 1900, just 6 years right after Marconi demonstrated his “wireless” radio, devices had been currently being installed aboard ships to allow them to acquire storm warnings transmitted from stations on shore. Right now, the very same principle applies in utilizing equally shipboard and land stations in the marine services to safeguard daily life and property at sea.

The two types of stations are also employed to support marine navigation, commerce, and personal company, but this sort of uses are secondary to security, which has global priority. The Marine Radio Providers contain the Maritime Mobile Services, the Maritime Mobile-Satellite Services, the Port Operations Support, the Ship Motion Support, the Maritime Fixed Service, and the Maritime Radio determination Service.

• Maritime Cell Service is an internationally allotted radio services delivering for safety of life and residence at sea and on inland waterways.
• Maritime Cell-Satellite Services provides frequencies for public correspondence in between ships and public coast stations as effectively as between aircraft and public coast stations and coast earth stations. The transmission of public correspondence from aircraft must not lead to interference to maritime communications.
• Port Operations Support supplies frequencies for intership communications relevant to port operations in coastal harbors, permitting the vessel targeted traffic to be managed a lot more efficiently while protecting the marine atmosphere from vessel collisions and groundings.
• Ship Movement Services gives frequencies for communications relating to the operational handling of the movement and the safety of ships and, in emergency, to the security of persons.
• Maritime Fixed Service supplies frequencies for communications gear set up on oil drilling platforms, lighthouses, and maritime schools.
• Maritime Radiodetermination Services offers frequencies for figuring out placement, velocity, and other qualities of vessels.

Together, shipboard and land stations in the Marine Providers are meant to serve the needs of the entire maritime neighborhood. The Federal Communications Commission (FCC) regulates these services the two for ships of U.S. registry that sail in worldwide and foreign waters and for all marine activities in U.S. territory.

For this and other factors, the rules make a distinction between compulsory consumers of marine radio for security at sea and noncompulsory uses for reasons other than security. In addition, policies about domestic marine communications are matched to needs of the U.S. Coast Guard, which monitors marine distress frequencies constantly to shield lifestyle and residence in U.S. waters.

Arelatively new category of wireless communication uses laser, occasionally named “free-space optics,” operating in the near-infrared area of the light spectrum. Employing coherent laser light, these wireless line-of-sight backlinks are utilized in campus environments and urban regions where the set up of cable is impractical and the functionality of leased lines is also slow.

Laser back links between web sites can be operated at the full local area network (LAN) channel velocity. And in contrast to microwave transmission, laser transmission does not require a Federal Communications Commission (FCC) license, and info traveling by laser beam can not be intercepted.

The lasers at every single area are aligned with a easy bar graph and tone lock method. Fiberoptic repeaters are used to connect the LANs to the laser units. Alternatively, a bridge equipped with a fiberoptic to attachment unit interface (AUI) transceiver could be utilized. Connections to and from the laser are created utilizing regular fiberoptic cable, defending info from radio frequency interference (RFI) and electromagnetic interference (EMI).

Monitors can be connected to the laser models to supply operational position, this kind of as signal strength, and to put into action neighborhood and remote loop-back diagnostics. The cause that laser items are not used very frequently for company applications is that transmission is impacted by atmospheric situations that generate such results as absorption, scattering, and shimmer. All a few can minimize the sum of light energy that is picked up by the receiver and corrupt the info getting sent.

Absorption refers to the capacity of different frequencies to pass through the air. Absorption is determined mostly by the h2o vapor and carbon dioxide content material of the air along the transmission path, which, in turn, is dependent on humidity and altitude. The gases that sort in the ambiance have a lot of resonance bands that let certain frequencies of light to pass.

These transmission windows arise at several wavelengths, this kind of as the visible light variety. An additional window happens at the close to-infrared wavelength of about 820 nanometers (nm). Laser goods tuned to this window are not significantly impacted by absorption. Scattering has a a lot better effect on laser transmission than absorption. The atmospheric scattering of light is a function of its wavelength and the amount and dimensions of scattering particles in the air.

The optical visibility along the transmission route is immediately associated to the number and dimensions of these particles. Fog and smog are the major conditions that tend to restrict visibility for optical-infrared transmission, followed by snow and rain. Shimmer is brought on by localized variations in the air’s index of refraction. This is caused by a blend of components, such as time of day (daytime warmth), terrain, cloud cover, wind, and the peak of the optical route over the resource of shimmer.

These situations trigger fluctuations in the received signal stage by directing some of the light out of its meant route. Beam fluctuations may possibly degrade method overall performance by generating short-term signal amplitudes that strategy threshold values. Signal fades beneath these threshold values result in error bursts.

Vendors have taken actions to mitigate the results of absorption, scatter, and shimmer. For example, this kind of techniques as frequency modulation (FM) in the transmitter and an automatic gain management (AGC) in the receiver can minimize the effects of shimmer. Also, selecting an optical path several meters over heat sources can drastically minimize the results of shimmer.

Nonetheless, all of these distorting circumstances can differ significantly within a quick time span or persist for long intervals, requiring onsite expertise to continually good-tune the system. A lot of businesses merely can not chance regular or extended durations of downtime whilst the essential compensating changes are becoming made. As if all this ended up not enough, there are other possible difficulties to contend with, this sort of as thermal window coatings and the laser beam’s angle of incidence, each of which can disrupt transmission.

These difficulties are becoming conquer with more recent lasers that operate in the 1550-nanometer (nm) wavelength. A1550-nanometer delivery technique is powerful enough to go via windows, can supply signals below the fog blanket, and is protected plenty of that it does not blind the informal viewer who occurs to search into the beam. Up to 1 Gbps of bandwidth is obtainable with these systems—the equivalent bandwidth ability of 660 T1 lines.

There is also a distance limitation related with laser. The hyperlink generally can’t exceed one.5 kilometers (km), and one kilometer is favored. With 1550-nanometer programs, the sensible distance of the hyperlink is only 500 meters.

Despite its restrictions, laser, or free of charge-room optics, can present a important last link between the fiber network and the conclude user—including as a backup to a lot more typical techniques, these as fiber. Free-space optics, unlike other transmission technologies, are not tied to specifications or expectations development. Vendors just attach their gear into existing fiber-based networks and then use any laser transmission approaches they like. This encourages innovation, differentiation, and pace of deployment.