Mayans, Incas, And Aztecs Essay - 1586 Words

In 2012 everyone was convinced that the world was going to come to an end, there is one civilization that we can put the blame on, the Mayans. There were many myths and legends that come from the 3 major civilizations that we’ve all learned about; Mayans, Incas, and Aztecs. The Mayans, Incas, and Aztecs built great and legendary civilizations in Mexico, Central America, and South America and with understanding these three we get a better understanding of the early life in these places. The first of these three is the Maya civilization. Tracing back to the Mayans we go back approximately 3,000 years ago. They were centered in the lowlands Yucatan Peninsula where they lived in farming villages that is now what we call Guatemala. The Mayans set a high standard for pottery, architecture, mathematics, artwork, hieroglyphics, calendar making, and more... One of the most notable things they achieved were the many Mayan ruins, the Mayans built enormous and elaborate stone temples, stela, and other stone structures within their cities. It was unknown for some time how exactly they managed to quarry and move these large stones due to the fact at the time it was not known what tools they possessed or how they were transported because the Maya did not use the wheel. Many of the large structures in ancient Maya cities in Central America were constructed from limestone blocks. It was important to determine the process by which the Maya built these structures, and the effort put forth, inShow MoreRelatedMayans, Aztecs, And Incas Essay1540 Words   |  7 PagesThe Aztecs, Mayans, and Incas were civilizations that settled in Central and South America thousands of years ago. There are vastly similar to each other, but also very different. They each had their own ways of growing their civilizations into what they needed to be successful. They had their own cultures and ways of life, but the ideas of each of them similarly came together in one way or another. The Mayan civilization was located in Central America on the Yucatan peninsula and down into theRead MoreIncas Versus The Aztecs And Mayans Essay1315 Words   |  6 PagesIncas versus the Aztecs and Mayans The incas rose in 1438, they fell in 1533. They suffered the attacks of Spanish conquerors such as Spaniard Francisco Pizarro (1475-1541) and the spread of small box. At the peak of power the civilization extended 4,000 km (2,500 miles) and included 16 million people. They were extremely advanced, had an army, laws, roads, bridges, and tunnels. Inca’s were the most advanced civilization because of their government, agriculture, architecture and technology comparedRead MoreThe Decline Of The Mayan, Aztec, And Inca Empires837 Words   |  4 PagesThe Decline of the Mayan, Aztec, and Inca Empires From 250 A.D. to the late 1500’s A.D., three civilizations, the Mayans, the Aztecs, and the Incas controlled Central and South America. Their decline happened for many different reasons. The Spanish conquistadors was one of the most common and deadliest, due to their advanced weapons and diseases they brought. It seems that wherever the Spanish went, bad things always happened. Innocent people were killed for no reason, cities were massacred andRead MoreEssay about Mayan, Inca, and Aztec Civilizations788 Words   |  4 PagesMayan, Inca, and Aztec Civilizations The Mayan, Inca, and Aztec civilizations each originated from Latin America. The Mayans lived in southern and central Mexico, other Mayans lived in Central America in the present day countries of Belize, Guatemala, and ancient Honduras. The Incas lived along the long coastal strip, and in the high peaks and deep fertile valleys of the Andes Mountains, and along the edges of the tropical forest to the east; this would be the country of Peru, Ecuador, ChileRead MoreRoom 1 - The Magnificent Mayans1213 Words   |  5 PagesMagnificent Mayans Culture Artifact 1: Ceramic Bowl Picture/Source: Ceramic Bowl (Britannica 1) Description/Source: This artifact shows a ceramic bowl that was used by the Mayans in everyday life for pottery making and used in everyday art. Artifact 2: Ruins from a Mayan Temple Picture/Source: Ruins from a Mayan Temple (Britannica 1) Description/Source: The ruins from the temple show religion in Mayan culture because this is where the Mayans went as a place of worship. Artifact 3: Mayan SculptureRead MoreEconomy in Early American Civilizations: Maya, Aztecs and Inca865 Words   |  4 Pagessocieties were very similar. One of these societies, the Mayans, lived in southern Mexico and northern Central America from the 3rd to the 10th century CE, and they relied on the trade of goods such as obsidian and crops such as cacao beans. Another American civilization was the Aztec civilization. They were located in the Valley of Mexico around the 13th to 16th century CE, and they used slash-and-burn farming to plant crops to trade. The Inca Empire existed from the 13th to the 16th century CE alongRead MoreThe Aztecs Werelocated In Mexico, Built On A Series Of1180 Words   |  5 PagesThe aztecs were located in Mexico, Built on a series of islets in Lake Texcoco , and was divided in four cities. Itzcoatl successor Montezuma who took power in 1440 By the early 16th century founded in 1428. (found in the 13th century) Mexico-Tenochtitlan, commonly known as Tenochtitlan was a Mexica located on an island in Lake Texcoco, in the Valley of Mexico.Aztec Economy Trade and Currency. the aztec trade everything, it was really important to them they relied heavily on agriculture and farmingRead MoreIvilizations of the Americas: Mayan, Aztec, and Incan Civilizations786 Words   |  4 Pagesin 1539. The three most advanced civilizations were the Mayans, the Aztecs, and the Incas. All three civilizations made major accomplishments, all being added upon and used by other civilizations. For example, the Mayans had created a calendar with three hundred sixty-five and a quarter days. The Incas had created terrace farming to create better and a larger amount of crops. All of these civilizations have impacted the world today. Mayans developed a complex calendar with hieroglyphics as depictedRead MoreMayan, Aztec, Incan Dbq768 Words   |  4 PagesThe Mayan, Aztec, and Inca civilizations brought major accomplishments to the world today. These accomplishments established them as advanced societies during their time without the influence of Europe, Asia, and the Middle East. Some of these accomplishments ranged from agriculture to architecture and on to writing and trade. Such as, the Mayans with their agriculture system of chinampas and there monumental temple/pyramids, the Aztecs with their trading in the city of Tenochtitlan, and the IncasRead MoreDbq 9: Civilizations of the Americas1258 Words   |  6 PagesCivilizations of the Americas The Mayan, Aztec and Incan civilizations each contributed major accomplishments to the world today. These accomplishments established them as advanced societies during their time. The Incans built a large road system, devised a complex irrigation system and developed their own language. The Mayans constructed the largest structure known until modern times, made drastic accomplishments in mathematics, studied astronomy and formed a calendar. The Aztecs built well-organized cities

How to Help an Attention-Seeking Child in the Classroom

Its not uncommon for children in the classroom to do things to get your attention. Too much attention-seeking can be disruptive, causing trouble and creating distractions. The attention-seeking child will often interrupt a lesson by blurting something out. Their desire for attention is almost insatiable, so much so that the child often doesnt seem to care whether the attention they receive is positive or negative. In many cases, it doesnt even seem to matter how much attention you give them. The more you give, the more they seek. Causes of Attention-Seeking Behavior The attention-seeking child is in need of more attention than most. They seem to have something to prove and dont take as much pride intrinsically as they do extrinsically. This child may not have a sense of belonging. They may also suffer from low self-esteem, in which case they will need some help building their confidence. Sometimes, the attention-seeker is simply immature. If this is the case, adhere to the interventions below and the child will eventually outgrow their craving for attention. Interventions As a teacher, it is important to remain calm in the classroom even in the face of frustration. The attention-seeking child will always present challenges, and you must deal with them in an even-handed way. Remember that your ultimate goal is to help the child become confident and independent. When a childs attention-seeking becomes disruptive, sit down with them and explain that you have a number of children to work with each day. Provide them with a period of time that is just for them. Even a two-minute period before or after recess (a period where you can devote your attention exclusively to them) can be very helpful. When the child begs for attention, remind them of their scheduled time. If you stick with this strategy, you will find that it can be quite effective.Promote intrinsic motivation by asking the child to describe what they like about their work or how they performed. This is a great way to encourage self-reflection and help the child build confidence.Always commend the child on their improvement.During the childs special time, take time to boost their confidence by offering some inspiring words.Provide the child with responsibilities and a leadership role from time to time.Never forget that all children need to know that you care about them and that they ca n contribute in a positive way. It took the child a long time to become an extreme seeker of attention. Be patient and understand that it will take some time for them to unlearn this behavior.Remember that students, especially young students, dont always know what appropriate behavior is. Take time to teach them about appropriate interactions, responses, anger management, and other social skills. Use role-play and drama to help students understand other peoples feelings and perspectives.When you notice bullying, take the students involved aside and ask the bully to apologize directly to the victim. Hold students accountable for their harmful behavior.Have a zero-tolerance policy in place that is well understood.As much as possible, recognize and reward positive behavior.

Expected Pattern of Development from Birth to 19years Free Essays

Expected pattern of development from birth to 19years AgePhysicalCommunication and intellectualSocial,emotional and behavioural 0-3 monthsGross- waves arms and brings hands together over body. Fine-clasps and unclasps handsThrough crying and physical contact. Smiles back when they see a smiling face. We will write a custom essay sample on Expected Pattern of Development from Birth to 19years or any similar topic only for you Order Now . Babies may stop crying after they are picked up or by hearing a familiar voice. By 3 months they get excited when its time to feed 3-6 monthsGross-rolls over from back to front and moves head to watch others Fine-reaches for a toy and moves it from one hand to anotherEnjoys rhymes and action songs. Uses sounds to gain attention. Can laugh showing a range of feelings. Stops crying when talked to and reaches out to be held. 6-12 monthsGross-sits unsupported and likely to be mobile e. g. rolling or crawling. by 12 months may stand alone briefly. Fine-grasps objects with index finger and thumb. Starts to babble and enjoys looking at books. They also watch and copy adults. Is affectionate towards family and primary carers but discriminates between strangers and family. plays peek-a-boo. 1-2 yearsGross-may walk holding onto furniture, by 2 years will walk unaided. Fine-uses spoon to feed, can hold own cup and will start to scribble. Also read: Child Development Not Following Expected Pattern Waves bye-bye, fingers point to objects to draw attention to adults. Less babbling and more recognisable words e. g. â€Å"no†,†come†Cries when left with someone they don’t know. keen to explore as they become more confident. Also interested in other children but does not play cooperatively. 2-3yearsGross-uses sit and ride toys and able to run. At this stage they are able play on slides. Fine-draws circles and turns pages in books. Points to pictures of familiar objects and names them. Start to recognise shapes. Starting to use sentences or putting words together. Playing imaginatively e. g. on the home corner. Shows kindness Begins to understand anger and feelings. Gets frustrated when they don’t get what they want. Separation from carers remains an issue for some unless they know who they staying with. 3-4yearsGross-walks upstairs with alternate feet. Runs backwards and forwards. throws a ball. Fine-draws face with features washes and dries hands with help. Use language to say how they are feeling because speech is understandable most of the time. Can name some colours and can verbally count to 10. constantly asks questions. Listens attentively to age appropriate stories. Start to understand the consequences of own behaviour. Can express their thoughts resulting in decrease in tantrums. Seeks approval from adults. 4-5 yearsGross- aims and throws ball, walks in a line. Climbs ladders, tree and playground equipment. Fine-draws a person with head, trunks and legs. Memory develops which allows recall of songs and rhymes. Imagination develops. Start to understand symbols e. g. writing and reading. Aware of others emotions and gender roles. Will follow basic rules and seeks play with peers in groups. Attends to own toilet needs 5-6 yearsGross- runs quickly and able to avoid obstacles. throws a ball to a partner and catches it. Fine-has control of pencil to form letters. Colours in pictures. Attention span increases and the development of vocabulary extends communication. Most children know the alphabet and can name upper case and lower case. Enjoy a joke. Physical care needs are developed. Understand the rules of games. Often has one or two focused friendships. 6-7yearsGross-hops skips and jumps confidently, balances on a beam and uses wheeled toys e. g. roller skates. Fine-cuts out shapes accurately. ties and unties shoelacesShows reasoning skills but still using trial and error learning. Able to carry adult like conversations. Uses appropriate verb tenses, word order and sentence structure. Have strong friendships. Develops self help skills e. g. wiping up spills. Uses language rather than tantrums or physical aggression to express displeasure. 7-12 years Gross- Increased coordination skills which allow more concentration on games like football/netball. Fine-skills are refined allowing work like model making and typing. Able to reason and use logic to solve problems. Show creativity in role play. Begins to use information form one situation and transfer to another. Some are keen to show inappropriate behaviour to gain attention from adults and admiration from other children. 12-19 yearsPuberty begins for boys between 14-17 years and for girls between 13-16 years. May became sexually active Gross-stamina increases which allow for them to walk for longer distances and take part in energetic sports. Fine -increase of strength in hands enables movement such as twisting lids of jars. Question sources of information e. g. parents,books and teachers. Start to change physically and hormones affect their mood. Making a transition from dependence on family to independence. How to cite Expected Pattern of Development from Birth to 19years, Essay examples

Internet Essay Example For Students

Internet Essay Emanuel HALAPCIUCRuxandra ICAInternet-ul si (r)evolutia comunicatiilorFac. Management, anul II, gr.126Cuprins: ? Internetul aparitie, scurt istoric? E-business, afacerea sec. 21? Nevoia de viteza si noile tehnologii de comunicatie? Mobilitate maxima: cu Internetul la plimbare? Tendinte pentru viitorul apropiat? Bibliografie Acum 4 decenii se lansa cu mare pompa primul satelit de comunicatii, Echo 1. La acea vreme, evenimentul capta atentia intregii lumi. Azi, lansarea unui satelit e ceva banal. Anul trecut, IRIDIUM (reteaua globala de telefonie mobila) declara ca mai are de lansat doar citiva sateliti, pentru a fi operationala in orice punct de la suprafata Terrei. Un exemplu sugestiv despre cum a evoluat societatea informationala Si totusi, lansarea lui Echo 1 este un eveniment exceptional. Pentru ca a deschis un nou univers: transmiterea aproape instantanee a informatiei din orice punct de pe glob, in orice punct de pe glob. Practic a redefinit conceptul de comunicatii. Si din 1960 incoace, acest concept se modifica de la o zi la alta. Ceeea ce ieri era idee revolutionara, miine va fi deja demodat. Permanent se impun noi standarde, in care cuvintele cheie sunt:mai rapid, mai eficient, mai ieftin. Si principalul respnsabil este INTERNET-ul. Internetul aparitie, scurt istoricEmbrionul Internetului se numeste ARPANET, si a aparut in 1969. A fost creat de ARPA(initialele vin de la Advanced Research Project Agency), faimosul proiect al Departamentului de Aparare al SUA. Scopul sau era pastrarea controlului asupra armelor atomice in cazul unui atac nuclear. ARPANET-ul a fost conceput initial ca o retea la nivel restrins, intre centrele de cercetare academice, industriale sau guvernamentale. Primele noduri ale retelei au fost Stanford Research Institute, Ucla, UC-Santa Barbara si Utah University. Oamenii de stiinta au realizat insa potentialul urias pe care-l avea acest sistem de transmitere a datelor in dezvoltarea industriei comunicatiilor. Intr-adevar, treizeci d e ani mai tirziu de la inventarea primei masini electronice de calcul, reteaua mondiala de calculatoare interconectate cuprindea deja peste o suta de mii de computere. Si numarul acestora creste zi de zi, intr-un ritm exponential. Pentru a se ajunge insa la asemenea performante, Internetul a suferit o serie de modificari, menite sa-l faca cit mai accesibil unui numar cit mai mare de utilizatori. Merita aici mentionata dezvoltarea primului program WWW(initialele de la worldwide web), in anul 1990, care stabilea o orientare grafica pentru retele. Un an mai tirziu, fisierele worlwide web devin accesibile pe Internet. Tot in 1990, apare primul sistem de cautare a fisierelor pe Internet, numit Archie. Odata cu aparitia www, asistam la un adevarat boom al Internetului. Noua interfata grafica permite practic oricui stie sa citeasca acces la un urias volum de informatie. Astfel ca, in 1992 numarul conectate la Internet depaseste un milion. De asemenea, pentru facilitarea manevrarii datelor, au aparut pe parcurs o serie de protocoluri si standarde de transmisie a datelor. Astfel, in 1971 se stabilesc standardele pentru doua tipuri de procese fundamentale: Telnet, pentru conectarea mai multor calculatoare la retea, si FTP(file transfer protocol), pentru transferul de fisiere intre calculatoare. In 1979, se infiinteaza Usenet, primul sistem de transmitere a informatiilor pe retea intre diferite grupuri de lucru. Nu in ultimul rind, trebuie mentionata suita de protocoale Transmission Control Protocol si Internet Protocol, cunoscuta azi ca standardul TCP/IP. Si zi de zi, apar noi si noi standarde, care fac din Internet un instrument mai atractiv si usor de utilizat. Practic asta a fost se cretul succesului. E-business, afacerea sec. 21Prima forma de comunicare pe Internet, intre 2 utilizatori, a fost e-mail-ul. Desi pentru multi pare o gaselnita recenta, e-mail-ul are venerabila virsta de 28 de ani. Fata de posta clasica, succesul e-mail-ului se datoreaza faptului ca nu trebuie sa te deplasezi pina la posta ca sa-l expediezi. Si ajunge aproape instantaneu la destinatie.posta electronica este astazi un mijloc zilnic de comunicare in afaceri, permitind ca datele si mesajele sa fie transmise instantaneu clientilor, furnizorilor etc. Insa asta a fost numai inceputul. Conceptul de e-business a redefinit modul de a face afaceri. Unul din pionierii e-biz-ului a fost Jeff Bezos. Fondatorul Amazon-ului, cel mai mare magazin on-line din lume, a profitat de faptul ca in anii 1992-94, Internetul cunostea un ritm de dezvoltare de circa 300% pe an. Initial deschis intr-un depozit, astazi Amazon.com este cunoscut oricarui aproape web-surfer. Secretul succesului? Faptul ca iti poti face cumparaturile de acasa, folosind cartea de credit, ca nu ai parte de vinzatori care sa te bata la cap, ca poti cumpara la orice ora din zi si din noapte, ca poti alege orice produs, mai ieftin ca la orice magazin sau supermarket. Pe cine n-ar tenta? Raspunsul ti-l poate da oricare din zecile de mii de oameni care cumpara zilnic de la Amazon. Astazi Bezos este unul dintre cei mai bogati oameni din lume. O performanta realizata in numai 4-5 ani. Si nu putini sunt cei care I-au urmat modelul. Astazi firme de renume ca Ford Motors, General Electr ic, Nike, si lista ar putea continua la nesfirsit, au magazine online. Rezultatele nu s-au lasat asteptate: crestei ale vinzarilor cu 20-30%. Mai mult, Ford si Toyota au promovat concepte de genulautomobilul in trei zile, prin care clientul primeste in cel mult 72 de ore masina pe care o doreste, de la dealer-ul cel mai apropiat. Pe deasupra, cu numai citeva click-uri de mouse, iti poti alege culoarea, echipamentele optionale, instalatia audio pe care o doresti etc. In prezent, un magazin online nu mai este un lux, e o necesitate. Concurenta e necrutatoare. Sintagma e-business or out of business e mai valabila ca oricind. Internetul este cu siguranta afacerea secolului 21. Furnizorii de servicii Internet inregistreaza cel mai mare suuces. AmericaOnLine, unul din primii ISP(Internet service provider), si cel mai mare ca numar de clienti, se situeaza astazi in topul firmelor americane. E de ajuns sa mentionam ca la inceputul acestui an, in luna februarie, AOL a preluat colosul mediati c TimeWarner, contra sumei de 195 miliarde USD. O firma infiintata de numai 5 ani a reusit sa preia un gigant ce dateaza din anul 1920. AOL este exemplul perfect pentru american dream: o firma infiintata intr-un garaj, de 2 tineri cu putini bani dar cu idei, reuseste sa atinga o cifra de afaceri anuala de cateva miliarde de dolari. Si am putea continua cu portalurile Yahoo, Altavista, Prodigy, Lycos etc. Firmele Internet-related fac legea pe pietele bursiere din intreaga lume. Anul acesta, scaderea pretului la actiunile Microsoft, cu 15,37 USD intr-o singura zi(30 martie 2000), a declansat un adevarat seism pe Nasdaq. Bursa nord-americana a inregistrat cea mai mare pierdere din istoria sa, de 349,15 puncte. O alta afacere de proportii ce are ca suport de desfasurare Internetul este e-banking-ul. De ce sa te mai duci pina la banca, sa stai la cozi interminabile si sa pierzi o groaza de timp pentru a depune sau retrage bani, cand o poti face comod, de acasa. Banca iti ofera la orice o ra din zi si din noapte situatia contului tau, iti poate sugera cele mai avantajoase posibiltitati de-a-ti plasa banii, sau ce suma maxima poti sa scoti din cont. Si asta pe gratis, si fara sa depinzi de amabilitatea unei casierite plictisite. Nimic mai simpluIn acelasi mod, poti fi un jucator redutabil la bursa fara sa fie nevoie sa iesi din casa. Poti cumpara sau vinde actiuni instalat comod in fotoliul tau de-acasa. Si pe orice piata bursiera din lume care permite tranzactii online. Si numarul celor care inca nu o fac este din ce in ce mai mic. Pentru ca oriunde e vorba de afaceri, Internetul face legea. Iti ofera viteza si mobilitate, restul depinde de tineNevoia de viteza si noile tehnologii de comunicatieUn element vital in modul in care va evolua afacerea ta online este aspectul magazinului tau. Pagina de web este vitrina magazinului, e cartea de vizita. Oricit ar fi de competitive ar fi produsele si/sau serviciile, nu le poti vinde daca nu exista clienti. Si singurul mod de a-ti atrage clientii este o interfata prietenoasa, atragatoare. Toate acestea inseamna insa sunete, animatii si alte aplicatii multimedia, ce au rolul de a atrage, de a face potentialul client sa-ti viziteze magazinul. Multimedia inseamna insa volum mare de informatie care trebuie sa se incarce la fiecare accesare a site-ului, ceea ce se traduce printr-un timp mare de asteptare. Apare astfel riscul ca potentialul cumparator sa se plictiseasca sa astepte, si sa incerce la alte magazine, care-I vor consuma mai putin timp si nervi. Dar daca scopul site-ului este tocmai promovarea de aplicatii multimedia, ca in cazul unei companii de film, care-ti prezinta tralier-e ale celor mai recente filme, sau al unei formatii muzicale, care, pentru a stirni interesul, in mod obligatoriu trebuie sa contina imagini si sunete? In plus, clientul tau trebuie sa vada ce cumpara. O fotografie a produsului pe care-l vinzi trebuie sa existe, chiar daca ea este de dimensiunea unui timbru. Cu prea putina inf ormatie, nu atragi clientii. Cu prea multa, ii alungi. O solutie ar fi atunci cresterea vitezei de transfer a informatiei. Viteza e cuvintul cheie in Internet. Internetul este eficient atita timp cit iti permite transfer al datelor la viteza mare, si cu distorsiuni cit mai mici. Altminteri cauti alte servicii, mai eficiente. De la lansarea lui Echo 1 in 1960, suprematia in comunicatii au detinut-o comunicatiile via satelit. Problema au constituit-o in schimb terminalele. Nu oricine isi permite o antena parabolica pentru emisia/receptia de la si inspre satelit. Problema s-a pus deci in sensul ca un grup cit mai mare de beneficiari sa aiba acces cit mai rapid la o singura antena. Si daca toata lumea este de acord ca cele mai eficienta cale de transmisie a datelor este transmisia prin satelit, problema vitezei apare la bucla finala, cum este denumita conexiunea de la centrala(ISP) la utilizatorul propriuzis. S-au dezvoltat in acest sens o serie de noi tehnologii. Unele au incercat sa i mbunatateasca reteaua deja existenta, altele au preferat orientarea spre modalitati noi de transmitere a datelor. Reteaua clasica o constituie chiar reteaua de telefonie fixa, care are avantajul unui cost redus de intretinere, in conditiile unei viteze rezonabile de transmisie. Sau asta cel putin pina acum citiva ani. Astazi modemul calsic nu mai satisface pretentiile din ce in ce mai mari ale consumatorilor de web. Prin constructie, linia telefonica nu suporta in mod normal mai mult de 56 kilobytes pe secunda. Insa si aceasta valoare este aproape imposibil de atins, datorita faptului ca pe o linie telefonica nu exista un singur utilizator, ci mai multi. O prima solutie, putin mai scumpa dar mai rapida a fost ISDN(integrated solutions for digital networking), care permite viteze de pina la 128 kb/sec. Serviciul combina serviciile de transmisie de voce si date prin aceeasi pereche de fire telefonice, astfel incit computerele se pot conecta direct la reteaua telefonica, fara a-si conv erti in prealabil semnalul in semnal audio analog. Aceasta integrare ofera o gama larga de posibilitati, care includ transmisii de voce, date, fax si switching. Cel mai important aspect pentru utilizatorii de ISDN este acela ca ofera o imbunatatire semnificativa a vitezei de acces, cu o crestere relativ minora de cost. In plus, pentru ca ISDN utilizeaza reteaua telefonica existenta, aceasta tehnologie este disponibila atit pentru firme, cit si pentru utilizatori individuali. Italian Renaissance Arts Affect On Persuasive EssayO alta tendinta in evolutia Internetului este mobilitatea maxima. Accesul la retea in orice punct de pe glob devine o necesitate pentru tot mai multi oameni. Internetul la purtator este un concept care reinventeaza telefonia celulara. Primii pasi in acest sens au fost laptop-urile, care impreuna cu un telefon mobil permiteau o conexiune Internet decenta. Un urmator pas a fost aparitia hand-heldurilor PDA (Personal Digital Assistants). Aceste dispozitive sunt un inlocuitor de succes al laptop-urilor si notebook-urilor, avind avantajul dimensiunilor mult mai reduse. Un PDA cu un minimodem incorporat si un telefon celular, iata primul model al Internetului de buzunar. Exista si PDA-uri mai avansate, care nu mai necesita nici macar telefonul mobil. Un exemplu in acest sens il constituie device-ul Palm VII, lansat cu un urias succes acum un an in SUA. Acesta dispune de un modem incorporat si un minibrowser care permit conectarea nonstop la Internet, contra unui abonament lunar (9 USD/luna). Din pacate, serviciul este disponibil numai pe continentul nord-american, extinderea lui la nivel global fiind considerata inca prea scumpa de catre Palm, compania care a lansat acest serviciu. O alternativa mai ieftina, care prinde din ce in ce mai mult teren, pare a ramine astfel reteaua de telefonie GSM. Ideea a fost implementarea browser-ului Internet direct in telefonul mobil. Se elimina astfel necesitatea laptop-ului sau a PDA-ului, ceea ce reduce costurile. Un browser este un client software proiectat sa permita accesul unui dispozitiv la servicii Internet, in combinatie cu un server de retea adecvat. Apare aici insa o problema. Popularele standarde de Internet HTML, HTTP, TLS si TCP sunt ineficiente si greoaie cind sunt folosite in retele mobile, intrucit presupun transmiterea unei mari cantitati de text. Continutul standard al unei pagini de Web HTML nu poate fi afisat eficient pe ecranele minuscule ale telefoanelor mobile sau pagerelor, iar navigarea intre mai multe ecrane este foarte dificila. HTTP si TCP nu sunt optimizate pentru intreruperile generate de iesirea unui utilizator de GSM din cimpul de acoperire sau pentru largimea de banda foarte limitata. Exista servicii fara fir care folosesc totusi protocoalele Internet clasice, insa aceste servicii sunt in general scumpe, lente si greu de folosit. Standardul de securitate TLS(Transport Layer Security) presupune un schimb intens de date intre client si server, ceea ce, in conditiile comunicatiilor mobile, se traduce printr-un raspuns foarte lent pentru utilizator. Solutia pentru toate aceste probleme este un nou protocol, de dicat comunicatiilor mobile: WAP(Wireless Application Protocol). Avantajul WAP este ca poate fi folosit in diverse tipuri de retele fara fir, si nu numai pentru GSM. Mai mult, include un mediu pentru aplicatii programate in WML(Wireless Markup Language), compatibil cu orice sistem de operare existent, de la Palm OS, la EPOC, Windows CE, FLEX- OS, OS/9, Java OS, etc. In termeni simpli, srandardul WAP este alcatuit din doua elemente: un mediu si un protocol de aplicatii. Mediul de aplicatii consta din WML, descris mai sus, si bazat pe XML(eXtended Markup Language) care permite programatorilor sa defineasca interfata cu utilizatorul independent de dispozititvul care o va afisa, si un limbaj de programare, WML-script, care permite inglobarea logicii executabile in aplicatiile proiectate. Modelul de protocol WAP este similar cu cel WWW. Acest lucru prezinta multe avantaje in comunitatea dezvoltatorilor de aplicatii, incluzind un model de programare si o arhitectura similare. Evident, pentru a se putea incadra in caracteristicile mediului wireless, WAP a trebuit sa fie modificat si adaptat. Intr-o retea tipica WAP, clientul comunica cu doua servere. Adresa de proxy translateaza apelul WAP in apel WWW, permitind astfel clientului sa trimita apelul la serverul web. Daca serverul raspunde direct cu o informatie de tip WAP(de exemplu in format WML), proxy-ul preia informatia direct de la server. Totusi, daca informatia este trimisa in continut WWW, (de exemplu in format HTML), atunci se va utiliza un filtru pentru a translata informatia in WML, sau in alt format recunoscut de WAP. Utilitarele de WAP sunt interactive si bazate pe un sistem de meniuri. Exista terminale care suporta grafica, icon-uri, seturi de fonturi, iar tendinta este de a asigura un ecran cit mai cuprinzator pentru telefonul celular WAP-ready. Telefoanele de ultima generatie pot fi programate manual, folosind meniul aparatului. In viitorul apropiat, acest proces va putea fi simplificat considerabil prin trimiterea unui mesaj SMS, iar setarile vor fi ajustate automat. In acest domeniu, virful de lance il reprezinta colosii telefoniei mobile clasice: Nokia, Motorola si Ericsson. Motorola a lansat recent modelul Timeport, care pe linga cardul SIM mai poate citi si cardul bancar. Avem astfel de-a face cu primul telefon WAP-able cu care putem face cumparaturi pe Internet. Ericsson a ajuns deja la al treilea produs de acest gen. Nokia a lansat deja o suita de aplicatii WAP proprii, care se bucura de un real succes: serviciul de cotatii online, serviciul de stiri realizat in colaborare cu CNN, etc. Tendinte pentru viitorul apropiatPentru urmatoarele luni, se prefigureaza o adevarata explozie a comunicatiilor fara fir. In intreaga lume, ritmul de crestere a numarului de utilizatori de telefonie mobila este, in medie, de circa 1000% pe an. Iar WAP se prefigureaza a fi noul standard in telefonia mobila. Iridium, reteaua globala de telefonie prin satelit, se extinde rapid. Chiar daca momentan tehnologia este mai scumpa decit GSM-ul uzual, avantajele sale sunt indiscutabile: viteza mare de transfer, acoperire la nivel planetar, suport pentru WAP. Iar costurile vor scadea odata cu cresterea numarului abonatilor. Integrarea comunicatiilor la nivel planetar prin Internet este cuvintul de ordine in ITC. Bibliografie:? business week? pc magazineReferinte:? www.ibm.com? www.motorola.com? www.orange.com? www.iridium.com? www.ericsson.com? www.nokia.com? www.3com.com? www.palm.com? www.cnn.com? www.ge.comBusiness