Wireless Local Loop

Wireless Local Loop Wireless Local Loop Abstract-A local loop connects a subscriber to the service providers switch, this connection is usually a wire; typically copper wire. Advanced studies on the capabilities of copper wire as a transmission medium has made it possible to use the local loop to offer services other than the basic voice service. This technology known as digital subscriber line technology (DSL) utilizes the existing copper wires to provide high speed data services. Optical fibre is a better option particularly for its large bandwidth but cost restricts its use as a local loop. Wireless local loop eliminates the need for wires as the subscribers equipment is wirelessly connected to the providers network. Wireless local loop (WLL) is a popular alternative as it has been deployed in both developed and developing nations because of its advantages. With an ever increasing demand to access the internet, the wireless local loop has evolved seeking to meet such demand. This paper looks at the several wireless local loop technologies as well as its prospects and future as a medium for broadband wireless services. Keywords: Wireless Local Loop, Internet, Broadband INTRODUCTION The local loop refers to the circuit terminating at the subscribers premises connecting the subscriber equipment to the switch of the telecommunications provider. It is the last lap of the providers infrastructure over which services are delivered to the user, hence, the term â€Å"last mile† is also used to refer to the local loop. Copper wires have been the principal candidate for the local loop providing voice service for telephony. However, digital subscriber line technology (DSL) makes it possible to use existing copper wires to offer services other than voice such as data, video, and multimedia services. One form of digital subscriber line technology (DSL), asymmetric digital subscriber line (ADSL) is the most commonly used today. Optical fibre has a lot of advantages over copper wire and that makes it an excellent choice for local loop but its cost is prohibitive. Wireless local loop also known as radio local loop uses radio signals to complete the last lap to the users premises. Wireless local loop is particularly suited to remote locations providing access to providers infrastructure and in areas where the terrain makes it impossible to lay cables. Wireless local loop offers a number of advantages over its wireline counterpart. 1) Fast deployment 2) Low installation cost 3) Low maintenance cost 4) High system capacity There are several wireless local loop (WLL) technologies available, hence, the technology deployed for a particular area will depend on the population density and service needs of the users. The rest of the paper is organized as follows, in section II, the wireless local loop architecture is considered. Section III presents the wireless local loop technologies followed by the wireless local loop for broadband services in section IV. Section V concludes the paper. WIRELESS LOCAL LOOP SYSTEM ARCHITECTURE The wireless local loop architecture is shown in figure 1. The fixed subscriber unit (FSU) is an interface between subscribers wired devices and wireless local loop network. The wired devices can be computers as well as telephones. The fixed subscriber performs channel coding and decoding, modulation and demodulation, and transmission/reception of signal via radio. The base transceiver system (BTS) performs channel coding/decoding, modulation and demodulation as well as transmission and reception of signal via radio. The base transceiver system is also referred to as the radio port (RP). A base station controller (BSC) controls one or more base transceiver systems (BTSs) and provides an interface to the local exchange (switch) in the central office [22]. WIRELESS LOCAL LOOP TECHNOLOGIES A. Microcellular based systems These systems provide low delay, low power and high quality services in a small coverage area. Compared with the cellular based wireless local loop, more base stations are required to cover the same service area. They are typically operated at 800MHz, 1.5GHz, 1.8GHz, and 1.9GHz frequency bands [77]. 1) Personal access communication system (PACS) Personal access communication system (PACS) is a low power radio system for both personal communication system applications and for fixed wireless loop applications. Personal access communication system is optimized to provide basic capabilities to support wireless local loop and additional capabilities to support mobility. The service capabilities of personal access communication system include voice, fax, voiceband data, and wireless digital data. The basic personal access communication handset can handle user with vehicle speeds up to about 50km/hr []. The personal access communication system architecture is shown in figure 2. The radio port (RP) function as radio frequency (RF) modems. Personal access communication system (PACS) uses time division multiple access (TDMA) on the uplink and time division multiplexing (TDM) on the downlink. The personal access communication system protocol supports switching to alternate channels when one radio port (RP) is busy [36]. 2) Personal handyphone system (PHS) Personal handyphone system is a low range personal communications services (PCS) technology that was developed in Japan to support very high density pedestrian traffic and wireless local loop. It is built on a foundation of digital cordless technology and microcell architecture [26]. Personal handyphone system (PHS) personal stations consist of handheld units that can operate as simple cordless phones, as transceivers for communications with other personal stations, or as mobile terminals to access the public switched telephone network (PSTN). The mode of operation must be selected by the user [26]. 3) Digital enhanced cordless telecommunications (DECT) Digital enhanced cordless telecommunications (DECT) is a radio interface standard developed in Europe mainly for indoor wireless applications [26]. Digital enhanced cordless telecommunications is a flexible digital radio access standard for cordless communications in residential, corporate, and public environment. In Europe, digital enhanced cordless telecommunications utilizes the 1880-1900 MHz frequency range. The DECT radio interface is based on the Multicarrier/Time division multiple access/Time division duplex (MC/TDMA/TDD) radio access methodology. Basic DECT frequency (1800-1900 MHz) is allocated to 10carrier frequencies, and the time is organized in frames. Each frame lasts for 10ms and consists of 24 timeslots separated into two fixed parts [37]. The fixed part (FP) consists of three entities; radio fixed port, central system, interworking unit. The radio fixed port terminates the air interface protocol. The central system provides a cluster controller functionality managing a number of radio fixed ports. The interworking unit provides all the necessary function for the DECT radio system to interwork with the attached wireline network; which can be: the public switched telephone network (PSTN), and the packet switched public data network [36]. B. Cellular based systems These systems are characterised by large power, high mobility and relatively low data rate over a large area. Cellular wireless local loop technologies are primarily used to expand the basic telephony services. Typically, they operate in the mobile frequency bands at 800-900 MHz, 1.8-1.9 GHz, and sometimes at 450 MHz or 1.5 GHz. For relatively sparsely populated rural and even urban settings, wireless local loop technologies based on existing cellular systems can be economical and rapidly deployed [77]. 1) Time division multiple access (IS-136/GSM) Time division multiple access (TDMA) is a multiple access technique which divides a channel into a number of timeslots. For TDMA system, there are two prevalent standards: North American telecommunications/electronics industry association (TIA/EIA) IS-136 and European telecommunications standards institute (ETSI) global system for mobile telecommunications (GSM). The IS-136 standard uses Ï€/4-Quadrature phase shift keying (Ï€/4-QPSK) modulation scheme while the GSM standard uses Gaussian minimum shift keying (GMSK) modulation. Also the channel bandwidth of the two systems is different (30 kHz for IS-136 and 200 KHz for GSM). GSM has a frame length of 4.615 ms instead of 40 ms for IS-136 [26]. Although GSM currently dominates mobile digital cellular and provides high quality voice, there has been little activity in using GSM as a wireless local loop platform. Being designed to handle international roaming, it carries a large amount of overhead that makes it unwieldly and costly for wireless local loop applications [36]. 2) Code division multiple access (IS-95/W-CDMA) Code division multiple access (CDMA) is a multiple access technique that employs spread spectrum technique. CDMA (IS-95) is a direct sequence spread spectrum (DSSS) system where the entire bandwidth of the system 1.25 MHz is made available to the user. The bandwidth is many times larger than the bandwidth required for transmitting information [26]. IS-95A standard has been TABLE 1 SUMMARY OF WIRELESS LOCAL LOOP SERVICES developed for a digital cellular system with direct sequence (DS) CDMA technology, operating at 800MHz band. IS-95 based CDMA wireless local loop can support two rate sets. A code channel (traffic channel) operates at a maximum of 9.6 kbps with the rate set 1 or 14.4 kbps with rate set 2. IS-95B offers high speed data services through code aggregation. In IS-95B systems, multiple codes (up to eight codes) may be assigned to a connection [22]. In CDMA systems pseudo-noise (PN) sequences are used for the different user signals with the same transmission bandwidth [26]. Wideband code division multiple access (W-CDMA) in comparison with narrowband CDMA systems (IS-95) use higher chip rate for direct sequence spread spectrum and, thus, spread its information into wider spectrum bandwidth (typically, equal to or over 5 MHz). Thus, data rate per code channel in W-CDMA can be higher than that in narrowband system. The wireless local loop standard defines several options for voice codecs: 64 kbps PCM, 32 kbps ADPCM, 16 kbps LD-CELP, and 8 kbps conjugate structure algebraic-code-excited linear prediction (CS-ACELP) [22]. CDMA based systems offer higher capacity and flexibility compared to other digital standards [36]. C. Satellite based systems These systems provide telephony services for rural communities and isolated areas such as islands [26]. These systems can be either of technology designed specifically for wireless local loop applications or of technology piggybacked onto mobile satellite systems as an adjunct service. Satellite technology has been used to provide telephony to remote areas of the world for many years. Such systems provide an alternative to terrestrial telephony systems where landlines are not cost effective or where an emergency backup is required [77]. A user can access the public switched telephone network (PSTN) via satellite indirectly from a wireless local loop facility through a small satellite terminal and a geostationary earth orbit (GEO) satellite. A very small aperture terminal (VSAT) terminal usually includes a 0.6-2.4 m dish antenna and a transceiver radio (outdoor unit) as well as a set of baseband and intermediate frequency (IF) subsystems (indoor units). In hybrid architectures, the VS AT is connected to a wireless local loop base station through the local switching exchange [24]. D. Proprietary systems These systems are considered proprietary because they are not available on the public wireless networks and are typically customized for a specific application. They generally do not provide mobility. Proprietary systems are, therefore, positioned to provide basic fixed wireless telephony. WIRELESS LOCAL LOOP FOR BROADBAND SERVICES For services requiring large bandwidths, such as video on demand, broadband wireless systems are suitable because of their higher frequency ranges. A. Local multipoint distribution systems (LMDS) Local multipoint distribution systems (LMDS) is a radio based access technology with cellular architecture offering flexible high capacity connections to private users and organizations [8]. Depending on the particular spectrum allocation policy, operation of LMDS systems take place at millimetre waves (typically 28 GHz in the United States and 40 GHz in Europe), enabling the exploitation of more than 1GHz operational bandwidth. This allows a plethora of multimedia services at data rates of hundreds of megabits per second [2]. Interactive LMDS has a point to multipoint downlink and a point to point uplink. The capacity of the return channel is determined by the needs of the individual user [8]. B. Worldwide interoperability for microwave access (WiMAX) Worldwide interoperability for microwave access (WiMAX) is a wireless communication technology capable of providing very high data rates over a large area. According to standards, WiMAX can support up to a 75 Mb/s data rate (single channel) and cover up to 30 miles [6]. The technology can provide fast and cheap broadband access to areas that lack infrastructure such as rural areas [4]. WiMAX technology supports two network modes: point to point (PMP) and mesh. A PMP network is designed primarily to provide for providing last mile access to the service provider, it consists of a base station (BS) and subscriber stations (SSs) and both uplink and downlink channels are shared among the subscriber stations. PMP mode requires all subscriber stations to be within the transmission range and clear line of sight (LOS) of the base station. The mesh network, on the other hand, is a multihop ad hoc network in which all nodes act as relaying routers in addition to their sender and receiver roles [1]. CONCLUSION The advantages of wireless local loop over the wired loop especially in the areas of fast deployment and installation cost continue to make it an attractive option for rural areas and difficult terrains. As with most wireless communication systems, the quality versus coverage area compromise remains an issue. However, the emergence of broadband wireless systems promises quality service over a considerable area, though, cost is a limiting factor. The wireless local loop market is expected to continue to grow in developed countries to compete with wired loop providers and in developing countries to connect many that are without service. REFERENCES [1] D.G. Jeong, and W.S. Jeon, â€Å"Current and future services using wireless local loop systems,† International Journal of Communication Systems, vol 13, pp. 289-301, 2000. [2]A.R. Noerpel, and Yi- Bing Lin, â€Å"Wireless local loop: Architecture, Technologies and Services,† IEEE Personal Communications, pp. 74-80, June 1998. [3] N. Cotanis, and B. Jabbari, â€Å"Wireless local loop radio systems,† Computer Networks, vol 31, pp. 343-352, 1999. [4] I.S. Barbounakis, P. Stavroulakis, and J.G. Gardiner, â€Å"General aspects of digital technologies for wireless local loops,† International Journal of Communication Systems, vol 13, pp. 187-206, 2000. [5] Th. Zahariadis, â€Å"Evolution of the wireless PAN and LAN standards,† Computer Standards and Interfaces, vol 26, pp. 175-185, 2000. [6] R. Conte, â€Å"Satellite rural communications: telephony and narrowband networks,† International Journal of Satellite Communications and Networking, vol23, pp. 307-321, 2005. [7]A. Nordbotten, â€Å"LMDS and their Application,† IEEE Communications Magazine, pp. 150 -154, June 2000. [8] A.D. Panagopoulos, P.M. Arapoglou, J.D. Kanellopoulos, and P.G. Cottis, â€Å"Intercell Radio Interference studies in Broadband wireless networks,† IEEE Transactions on Vehicular Technology, vol 56, No. 1, pp. 3-12, January 2007. [9] K. Lu, Y. Qian, H. Chen, and S. Fu, â€Å"WiMAX Networks: From Access to Service Platform,† IEEE Network, pp. 38-45, May/June 2008. [10] Z. Abichar, Y. Peng, and J.M. Chang, â€Å"WiMAX: The Emergence of Wireless Broadband,† IT Pro, pp. 44-48, July/August 2006. [11] K. Lu, Y. Qian, and H. Chen, â€Å"A Secure and Service-Oriented Network Control framework for WiMAX Networks,† IEEE Communications Magazine, pp. 124-130, May 2007.

Literary Analysis on Revelation Essay

Flannery O’Connor short story entitled â€Å"Revelation† was swayed by her personal upbringing in the South. She lived in the time where people from the South were very intolerant and narrow-minded towards people who had a different lifestyle and who were of a different race. Because Southerners believed people who did not live up to their wealth or status were inferior, it offered O’Connor the exact descriptions she wanted for the characters in this story. The main character in this story, Mrs. Turpin, is extremely prejudice and uses many terms of racial terminology. All of the characters in this story are well-known by their physical looks, and some are well-known by the racial terms used in the story. Mrs. Turpin said that the higher class women were â€Å"well-dressed and pleasant. † Another time she refers to a poor woman as â€Å"white trashy† and a teenage female as â€Å"ugly. † We are able to understand the lifestyle of the South that Flannery O’Connor was a part of in her childhood by her choice of words in this story. An example, when Mrs. Turpin would talk to her black laborers. There seems to be a major and minor social divergence in the story. The minor conflict is between the â€Å"white trash† woman and Mrs. Turpin; the problem stems from Mrs. Turpin thinking that she is in a higher class than this particular â€Å"white-trash† woman and most people. Mrs. Turpin is disgusted because the â€Å"white-trash† woman interrupted Mrs. Turpin’s conversation with someone else. In the story we are given the image that not only is the woman â€Å"white-trash† but she is uneducated and unintelligent. This is another example made clear to the readers of the background of O’Connor because the character is not given a real name but a disparaging title. The major conflict of this story occurs with the teenage girl and Mrs. Turpin. The conflict is not given away at one point in the story but gradually develops between the two women with many different facial expressions given by the teenager. Mrs. Turpin says that the girl gave her, â€Å"The ugliest face she has ever seen anyone make. † The action that occurs because of the conflict is something the readers did not see coming, which makes the story an even better read. The teenage girl hits Mrs. Turpin in the face with a book while she is in conversation with someone else. With this action, O’Connor was able to use an unfortunate finale for this story. Mrs. Turpin was confident in who she was as a person; she believed that she was merely good and could not understand why she is not liked. The story ends with all of Mrs. Turpin’s questions being unanswered and that leaves her with a sadness that is insoluble. Through the use of the conflicts created in the story there is the element of astonishment, a sad ending, and an authentic plot. The characters of this story are bullied and seem to be descriptions of lower intellect. On the contrary, Mrs. Turpin is supposed to appear to be of common intellect. The conduct of Mrs. Turpin really emulates the image O’Connor was given in the South. Mrs. Turpin is a very nice individual and extremely sociable and she observed the people around her and started conversations with anyone who would listen. Another characteristic of Mrs. Turpin is her plausibility, she seems to be this way because her actions exemplify a believable person. O’ Connor makes Mrs. Turpin to be the exact model of a â€Å"Southern Citizen† with the same attitude of a Southerner. O’Connor did a great job of using many literary devices, mainly symbolism, which helped her emphasize the theme of this story. Mrs. Turpin is extremely disliked by teenager from the beginning of the story all the way to the end of the story. The teenagers dislike for Mrs. Turpin propagates as the story continues and then seems to explode at the end which resulted in the action of hitting Mrs. Turpin. The book being thrown at Mrs. Turpin possibly symbolizes the distinctive types of social classes; the well dressed woman Mrs. Turpin converses with is a educated and high standard individual; and the â€Å"white-trash† woman is a uneducated and a low class individual. Another literary device used in this story is foreshadowing. Foreshadowing was seen by the teenage girl making facial expressions towards Mrs. Turpin. These actions showed a struggle between the two women. As the story continues the increase of these disrespectful actions foreshadows a disagreement between Mrs. Turpin and the teenager. In conclusion, foreshadowing as well as symbolism are the most important literary devices used by Flannery O’Connor in â€Å"Revelation. †

Childhood Memory

I am an international college student from Vietnam, and have been through twelve grades with lots of memories. One thing I could say is the interval time between my sixth and eighth grade was the time that I cherish the most. It is not only because it was my most successful time with a bunch of fabulous achievements I obtained, but also because literally it was my great pleasure to be instructed by a very thoughtful teacher. She was my Mathematics teacher, and her name is Mrs. Nguyen. I did enjoy most of her lectures in class. Thanks to being taught by a great teacher, Mathematics gradually became my most favorite subject. At that time, Vietnamese teachers received just a small amount of salary every month due to the government did not have much money. They could have a good life if they live alone, and only spend money for their own. However, if they have a family, their husband or wife needs to have much better income to run the house and nurture their children. My teacher and her husband both do educational job. As a result, they do not have good income enough to run their house and to pay tuitions for their kids. Therefore, those who had the same situation like this usually opened extra classes at their home for a little income. The government prohibited teachers to give extra lectures at their home because they worried that if teachers give lectures at home, students would get bored of listening lectures in class. Childhood Memory As a child everything was so much more simple. Day after day I only had one objective on my mind, and that was to go outside and have as much fun as I possibly could before the sun went down and it became dark, that was when I had to be home. My cousins lived right next to me so i can always remember going outside and swimming in our swimming pool, and then we would go over to our grandmothers house for lunch, she lived on the other side of my house right next door, I will never forget going over their amd smelling the freshly baked cookies she always made us.There are alot of things i can remember from my childhood but everytime I think back this one seems to always stand out the most. I will never forget the early morning that my dad woke me up on my birthday. He woke me up and told me to get ready because we had to go. I remember asking him over and over again why I was up so early, and where in the world do we have to go its my birthday what about when all my friends come over. H e told me to not worry because he had a special suprise for me, I was so excited but I couldn't think of what the suprise could be.Driving in the car felt like it was taking forever, I was so tired i fell back asleep in the back seat. Once we got there my dad woke me up again but this time when i opened my eyes i saw my cousin michael and my uncle donny standing right next to my dad. I remember asking what is going on and thats when my dad showed my the fourwheeler he bought me. I couldn't have been any happier at that moment I was jumping up and down overwhelmed with joy. e put the fourwheeler on my uncles trailer but there was already one on it, thats when my cousin michael told me that his dad got him one too. I was so happy because we did everything together, nobody could sperate us. I couldn't thank my father enough on the way home, a fourwheeler was my dream I always wanted to have one they looked like so much fun all of the my older friends and cousins had one not to mention all the video games that I played with them. I couldn't believe that I finally had one now all I needed to do was learn how to ride it.This was one of my biggest challenges because nobody ever showed me how. When we finally got home my dad and my uncle took both fourwheelers off of the trailer and my dad showed me what to do how to use the gas, turn and how to stop with the brake. He turned the fourwheeler on for me and I sped away having no clue what I was doing, my cousin followed right behind me but he already knew how to ride because his brother had a fourwheeler and he taught him what to do. We rode all the way to the fields in my backyard behind the apple orchard.Right before the field there's a hill that has a deer feeder on it close to the woods my dad hunts in, i decided to try and drive up the hill I guess i wasn't ready to do something that experianced because when I got halfway up the hill I stalled the fourwheeler and hit the back brake and the fourwheeler flipped over and I fell off rolling down the hill the fourwheeler landed on my hand. My dad came running down to me and picked me up because I was screaming thinking my hand was broken, I always over exaggerated everything when I was younger.I went up to the house and put ice on my hand because it was really swollen. That ended my day because when my mom came home she was so worried she didn't want to ride my fourwheeler anymore because she thought it was too dangerous. I tried to tell her that it was an accident and I just did something I shouldn't have tried yet. She told me I could ride it again if i waited for my hand to heal, but of course I didn't listen to anything my parents told me because I was a wild child.So the very next day I was back out riding again with my cousin but this time we took it a little bit easier and went slow and I wouldn't dare attempt the hill again. My mom was ferious when she found out that I was riding when I wasn't suppose to be. I was bound and determined to b e the better than my cousin someday but I doubted it because he was two years older than me and he was always bigger than me so he had an advantage because we had the same fourwhellers and i was a little bit to small for it.Everyday we would wake up at the same time around eight in the morning and we both would meet at my barn where we kept the fourwheelers and we would go up to the house and fill up our tanks with gas and go ride in the fields behind my house and across the street. we would come home at dinner time so filthy, we would be covered in mud from head to toe but we didn't care at all because we were kids just having the best time of our lives. Now that I reflect upon my childhood I realize that I do not regret any choices that I made because that's what made me happy.I had alot of fun as a child and I miss every second of it, I didn't have a worry in the world. Now that I am getting older and about to graduate from high school I know that those days are over. At this poi nt in my life I need to get down and stay focused and determined to live a successful life, I feel that if I put my mind to it I will be able to do it. Just like how determined I was to be better than my cousin everyday I practiced, and I soon became much better doing things that he still to this day can not do. My childhood was perfect and I wouldn't change anything about it, these memories will live on forever with me.

What is Plato trying to say in the Allegory of the Cave - Free Essay Example

Sample details Pages: 3 Words: 882 Downloads: 4 Date added: 2019/08/12 Category Philosophy Essay Level High school Tags: Allegory Of The Cave Essay Did you like this example? When he is approaching nearer to being and his eye is turned towards more real existence, he has a clearer vision (Plato, 2). Platos Allegory of the Cave can be interpreted in many different ways. It can be used to describe a variety of governments and its influence on the people, yet it can also be used in a religious sense as well. Don’t waste time! Our writers will create an original "What is Plato trying to say in the Allegory of the Cave?" essay for you Create order Even though Plato is writing from a non-Christian point of view, the Allegory of the Cave still serves as an illustration of a Christian Truth, that being those who are bonded to sin and darkness have difficulty pursuing righteousness and light, yet those who chose to seek the brighter light outside will benefit ones sanctification. At the beginning of the allegory, Plato describes the setting of the cave. The underground cave contains a mouth openly facing the light, which reaches along the cave. Those who are walking in the cave are bound by chains. The bindings are attached to their legs and necks, and while being forced to look only onward, it prevented the turning of their heads to see what was beyond the cave. On the other side, a blazing fire was used to cast the shadows of figures that were cast upon the walls of the cavern. The captives were only able to see those shadows, which they believed were their reality. The first part of the allegory is the bindings and the shadows. The cave that the people were in was a prison to them, and those in the cave have been enslaved since their childhoods. The prisoners are bound by chains, which made the prisoners unable to move. The shadows were cast upon the wall that the prisoners were forced to face. Since these shadows were the only thing the prisoners saw, they couldnt comprehend that there was a truer and greater reality waiting for them on the outside of the cave. If one was to attempt to look onward to the light outside, then he would experience severe suffering, for the light outside was so blinding. The prisoners were so used to the shadows, and the reality that they were forced to see, that they couldnt comprehend the light outside. These shadows were just a mere disguise, camouflaging the prisoners from what was real and true. Those who are bonded to sin have shadows in their own lives. They cannot see what is righteous and genuine, since th ey arent opening themselves up to the idea that the reality they see is simply an illusion. Sinners choose to only see the fake reality that is brought forth to their attention, while those who belong to God are able to see past the illusions, and look towards Christ. There is much more to life that meets the eye. However, the prisoners were forced to only see what was in front of them, because the shackles prohibited them from seeing a true reality. One day, a man came into the cave and released one of the prisoners. When his chains were broken, the captive, now living in freedom, walked along the side of the cave, watching the other prisoners. He noticed how the shadows on the walls were not real, and they were just the reflections of figures that were cast upon the wall. He saw how the prisoners were unable to see anything but the fake realities set forth for them. Once the man reached the mouth of the cave, he stepped out of the cave to see true light and sun for the very first time. His first step into the light brought him into a state of blindness, for he lived his entire life in the darkness of the cave. The power of true light was so overwhelming for him, that the reality that he once knew vanished into thin air. This man is an example of how those who are bound to sin are stuck living in the fake reality set up for them. Conversely, when they understand that they can live in the shadows no more, they are able to live a free life in the light, and that righteousness that they are stepping into makes them into a completely changed person. Their reality that they believed to once be true, is true no more. Everything they once lived for has absolutely no meaning, for they have found righteousness by pursing the light. The man who walked out of the cave and into the light left behind his old life, and his interpretations of his old reality, and moved toward living in a true reality. He stepped toward the light, hoping that the bondage he was once enslaved to is no more. By turning to the light, he is now able to live in a true life without sin having a hold onto him, just like how the freed man isnt bound to anymore more chains. In the bible, Isaiah 42:6-7 states, I, theLord, have called you to demonstrate my righteousness. I will take you by the hand and guard you, and I will give you to my people, Israel, as a symbol of my covenant with them. You will open the eyes of the blind. You will free the cap tives from prison, releasing those who sit in dark dungeons. This verse means