♥♥IT Consultant ?♥♥

An IT consultant works in partnership with clients, advising them how to use information technology in order to meet their business objectives or overcome problems. Consultants work to improve the structure and efficiency and of an organsiation\'s IT systems.
IT consultants may be involved in a variety of activities, including marketing, project management, client relationship management and systems development.
They may also be responsible for user training and feedback. In many companies, these tasks will be carried out by an IT project team. IT consultants are increasingly involved in sales and business development, as well as technical duties.

with IT at the heart of the organization, not only for transfer of the billions of purchases made through its reach, but also for the decision making prospects of its owner/customers, namely the banks that both use and own the service. All in all, these lively discussions show how radical decentralization works with technology and suggests that other organizations of the “here and now” can benefit from revisiting their information sharing services.

Common Impact seeks an IT Consultant to design technology solutions to meet our nonprofit
clients’ needs. For the past eight years, Common Impact has built the leading model that connects skilled
professionals from global companies to high-potential local nonprofits; the IT Consultant will be
responsible for facilitating these connections while helping Common Impact grow its own systems and
operations to new geographies. This is an exciting opportunity, reporting to our Managing Director, for an
experienced architect to design technical solutions for nonprofits’ greatest challenges, to join Common
Impact’s talented team, and to grow a proven model of social impact.

INTERNET
The Internet is a global system of interconnected computer networks that use the standardized Internet Protocol Suite (TCP/IP). It is a network of networks that consists of millions of private and public, academic, business, and government networks of local to global scope that are linked by copper wires, fiber-optic cables, wireless connections, and other technologies. The Internet carries a vast array of information resources and services, most notably the inter-linked hypertext documents of the World Wide Web (WWW) and the infrastructure to support electronic mail, in addition to popular services such as online chat, file transfer and file sharing, online gaming, and Voice over Internet Protocol (VoIP) person-to-person communication via voice and video.

TECHNOLOGY
Our schools thrive on information. In the ever-changing world filled with new technology, our teachers and students require the right information, from the right sources, today. Having direct access to industry information gives the competitive edge needed to succeed. Student performance can be improved when the enhancement of teaching and learning using technology is adopted as the norm.
Technology is the need of the day. The technological advancements have made society take a leap towards success. Every technological reform is a small step towards advancement. Every new invention in technology is a step towards progress of mankind. Centuries ago, hardly anyone would have even dream of working on a computer. Generations of the yesterday years would have hardly imagined being able to communicate with people on the other side of the globe. But there were some intelligent minds to dared to dream of such revolutionary discoveries and they made the \'impossibles\' possible. Ours as well as our future generations are lucky to be able to witness the technological reforms. We are fortunate enough to lead a life of luxury and comfort. Since ours are the times of technology, why not let the technological reform spread far and wide? Why not make the masses aware of the new technology? Why not equip the entire society with the knowledge of the new inventions in technology? Computers can offer livelier explanations of various subjects. The Internet is an ocean of information, which can be harnessed for the rendition of information in school.

Innovation refers to a new way of doing something. It may refer to incremental, radical, and revolutionary changes in thinking, products, processes, or organizations. A distinction is typically made between invention, an idea made manifest, and innovation, ideas applied successfully

Infrastructure
Infrastructure is the basic, underlying framework or features of a system or organization. Can be defined as the basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function. The term typically refers to the technical structures that support a society, such as roads, water supply, sewers, power grids, telecommunications, and so forth. Viewed functionally, infrastructure facilitates the production of goods and services; for example, roads enable the transport of raw materials to a factory, and also for the distribution of finished products to markets. In some contexts, the term may also include basic social services such as schools and hospitals.

Inorder for the internet connectivity to be improved and as an IT CONSULTANT, I would suggest the following.

DSL TECHNOLOGY

DSL (Eng. Digital Subscriber Loop) - a digital subscriber loop, the family of broadband access to the Internet technology. The standard data reception speed fluctuates between128 Kbps up to 24,000 Kbps, depending on the applied DSL technology and its level.
The commercial success of DSL and similar technologies is reflected in the fact that in the last decades, as electronics is becoming faster and cheaper, the costs of digging out pits for the new wiring have remained unchangeably high. All of the DSL technologies use highly complex algorithms for converting the digital signal, overcoming the inseparable limitations of wires` strands. Recently costs of a similar installation would have been incredibly high but thanks to VLSI technology, costs of installation of DSL in the already existing local terminals, with DSLAM multiplexer on one end and a DSL modem on the other, requires a smaller amount of expenditures that could arise at the same route and distance, when installing a new optic fiber.
DSL technology is used in majority of apartments and minor offices, the proper filters enable simultaneous operation of voice services and of DSL. DSL modem can use the same subscriber`s line that the communication devices based on POTS technology use, turning faxes and analogue modems on. At the same time, only one DSL modem can use the subscriber`s line. The standard method of making DSL available to many computers in the same premises is using a router, which connects the DSL modem and local Ethernet or Wi-Fi net. The channels of dispatch and receipt streams are used to obtain connection between the subscriber and Internet services supplier.

DVB-S TECHNOLOGY
DVB-S is currently one of the most popular methods of satellite access to the Internet. As every connection, DVB-S has its drawbacks and advantages resulting directly from its physical construction and laws that manage it. Major advantages include:

- Global reach - the technology in-question, given application of proper layout of the satellites on the orbits (rose or polar) provides practically global reach, including areas on greater latitudes (poles). Unfortunately, geostationary orbits, which provide access in areas on moderate latitudes (Europe etc.) are currently used in commercial solutions.

- flexibility - it is obvious that the technique consists in wireless radio transmission, in consequence of which, the client is independent of all types of cables connecting him to the operator. As a result, it allows for application of portable (operating without movement but with the possibility to move them) and mobile (with operation in movement option) access terminals, which conditions the flexibility through adjustment of the system for clients` needs.

There are a few problems connected with this kind of access. First of all, the operator must guarantee constant access to his network (constant access to services and incessant rendering of the given service). He is also obliged to provide proper quality of the services (QoS) and constant control of this parameter. Failure to fulfill these conditions may force today`s client with high expectations (ex. a bank) to use services offered by a different operator. The next problem is the maximal radiation power of the receiving-dispatching system (EIRP), which is strictly determined by Telecommunication Regulatory Offices in the given country. The remaining, rather important aspects include: right capacity of the system and provision the necessary bandwidths in proper frequency ranges.
A crucial feature of the teleinformatic system are minor delays in transmission. As it was mentioned before, construction of the link itself (precisely distance between the satellite and Earth) introduces certain limitations connected with the speed of propagation of the electromagnetic wave in free space. The picture below presents the possible orbits on which satellites can be located. Logically, the shortest transmission delays will take place in case of units placed closer to Earth. Theoretic transmission delays for individual orbits are:
- LEO (Low Earth Orbit) - from 2 to 50ms
- MEO (Medium Earth Orbit) - from 30 to 70ms
- GSO (GeoStationary Orbit) - approx.120ms
- HEO (High Eliptical Orbit) - undetermined value due to far too great changes of the distance from Earth in time function

The satellite access systems usually operate in two frequency bands: Ku (10-18GHz) and Ka (18-31GHz). Ka band was divided into two sub-bands: dedicated to the `downward` link (satellite-terminal) - 19.7-21.2 GHz and to the `upward` link (terminal-satellite) - 29.5-31 GHz. Moreover, application of the so-called V band(40-75GHz) is also planned in communication via satellite. Multi-access to the system is realized in MF-TDMA (Multi Frequency Time Division Multiple Access) system, which consists in separation of particular tome spaces for the user in a given (one of many) frequency band (3 transmission dimensions - time, frequency and level of the signal)

OPTICAL-FIBER TECHNOLOGY
FITL (Fiber In The Loop) - Fiber in the Loop system
the latest offer of world telecommunication concerns are fiber in the loop systems which enable common realization of various telecommunication and TV services. Such type of systems includes FITL system. FITL enables construction of a common network for rendering services to telephone and TV subscribers with limitation or complete elimination of hitherto used copper wires. FITL systems constantly try to live up to forever growing requirements towards public telephone network operators. Apart from provision of basic telecommunication services, such as telephone connectivity, more and more is said about the possibility to render services out of the basic range, such as multimedia services: video on demand, videoconferences, video telephone, quick access to the Internet, electronic shopping and so on. FITL system widely uses the fiber technique, recognized and tested in cable transmission lines. It assumes application of optical carriers, mainly in main or distributive part of a classic access network. Depending on location of the optical network unit, ONU, three types of network architecture can be distinguished: FTTB (Fiber To The Building), FTTC (Fiber To The Curb) or FTTH (Fiber To The Home). Name of a given architecture describes the place of location of ONU. All of these solutions can use the transport part of a telecommunication network to obtain access to the group of services, which is also based on the optical-fiber cable.
Reference models for FITL architecture

FITL system consists of the following elements:
a) OLT (Optical Line Termination) - termination of the optical line, sometimes called HDT (Host Digital Termination),
b) ONU (Optical Network Unit) - optical network unit,
c) ODN (Optical Distribution Network) - optical distribution network.

OLT, optical line termination, is a type of access net contact point with the access point to telecommunication services (depending on configuration of the network, it can either be an access group or directly the service group. ex. the telephone exchange). Physically the connection between OLT and one or more of the optical network units is realized via ODN on one or two optical fibers, depending on the applied transmission method (possible duplex, diplex or simplex). ONU, delivers application information of the given telecommunication service between ODN and the subscriber and the other way around. The contact point of the user with the access network is subscriber`s plug.

FTTC, FTTB, FTTH Architectures Specification
Depending on location on ONU module in the access net, three FILT network architectures are distinguished:
a) FTTC - Fiber To The Curb,
b) FTTB - Fiber To The Building,
c) FTTH - Fiber To The Home.

It must be noted, however, that the above specifications determine the level of penetration of an optical-fiber medium into the access network. Transmission from ONU to the subscriber is based on classical access net, i.e. traditional copper strand using one of the available xDSL transmission techniques. All of the above-mentioned solutions provide a sufficient band for present and future interactive, distribution, narrow- or broad-band applications.

WIRELESS LOCAL AREA NETWORK TECHNOLOGY
WLAN - Wireless Local Area Network - is at present probably the most popular and the most often used wireless way to access the Internet by the net users. However, this solution is not one of those that guarantees top quality of the services (QOS) but the price one must pay investing in the devices totally makes up for this drawback. The equipment, especially the 2,4 GHz, is relatively cheap and is still getting cheaper. That is why it is willingly used by minor Internet providers to solve the last-mile problem.
The IEEE 802.11 standard is promoted by the Local and Metropolitan Area Networks Standards Committee, IEEE Computer Society. Before it was approved in June 1997, it was preceded by six draft versions. Only its final shape was recognized by both IEEE and ISO/IEC standards. It enabled a big group of producers and salesmen to develop a wide range of devices for ISM (Industrial, Scientific and Medical) and UNII (Unlicensed National Information Infrastructure) bands on general release.

At present a few standards of WLANs are dominant. The most popular ones are the following: 802.11a, 802.11b and 802.11g. Due to this a few physical layers are defined, which give the designer the possibility to chose one of them, depending on the system requirements and future users� needs. The IEEE 802.11 standard defines two lowest layers of the wireless computer network model operating with the throughput in the radio linkup to 2 Mbit/s. It presumes two types of radio interface: operating within 2,4 GHz band and one using the IR. The original specification of IEEE 802.11 was characterized by low bandwidth and problems with co-cooperativeness.

802.11b specification, published in 1999, determined a new PHY layer which guarantees a greater bit speed with application of DSSS (Direct Sequence Spread Spectrum) in 2,4 GHz range. Devices operating in this standard can dispatch data with speed up to 11 Mb/s. 802.11a specification was presented in 2001 and it defines PHY layer operating in 5 GHz band. The maximum bandwidth was increased up to 54 MB/s, thanks to, among others, application of a new modulation method, OFDM (Orthogonal Frequency Division Multiplexing). 802.11g is the latest PHY specification, operating in 2,4 GHz range and using OFDM spectrum dispersing technique.

WLAN TOPOLOGY
a) The temporary net ad-hoc in the group of 802.11x standards is called IBSS net (Independent Basic Service Set). In order to created IBSS at least two devices are required (ex. computers) equipped with wireless network adapter cards. Such a web is not connected to a wireless net and, therefore, data exchange with the framework net is impossible (ex. access to sources, ex. Internet). Ad-hoc net does not require application of access points.
b) Dependent net (BSS - Basic Service Set) uses devices called access points, Aps. Their task is to reinforce and regenerate received signals, to manage movement and provide access to the wireless part of the infrastructure. The reach of a dependent network is limited to one access point within which the mobile station may move without breaking the connection.
c) Compound network (ESS - Extended Service Set) is created when at least two BSS sub-networks are connected to LAN; it is the most developed example of a combined network which can be successfully used for creating vast, combined, local computer networks.

WiMAX TECHNOLOGY
WiMAX is a wireless access to the Internet technology whose aim is to provide broadband access to the network to end users, mainly in cities. It is based on the American IEEE 802.16 and European standards ETSI HiperMAN. WiMAX is an alternative to wireless networks, especially in areas where telecommunication network structure is poorly developed. WiMAX provides optimal solutions of the so-called last-mile problem, i.e. leading the link to its end user. Both standards (European and American) make creation of many base stations` configurations possible, which, in consequence, may cause a situation in which devices made by different producers may not co-operate with each other. That is why WiMAX`s task is to standardize the method of devices` configuration - to solve this problem. The discussed solutions are supposed to guarantee the possibility of co-operation of the devices both with and without direct optical visibility of the aerials and they also give operators the possibility to extend their range of access to the Internet services with mobility by creating competitive solutions (VoIP) for mobile networks. Solutions described in the hereby article refer to 802.16 standard and that is why it is worth to begin with presentation of the standards in-question. It was created from 1999 and, as one may expect, many versions of it have hitherto been created. At the moment two of them are valid:

- 802.16-2004 finished in 2004, it offers access to the network for terminals that are not on the move.
- 802.16e finished in 2005, it offers access to the network for terminals that are either stationary or on the move. Certification of devices that comply with this standard should begin in 2007. As I have already mentioned, the technology does not require direct visibility of the aerials, therefore it uses the NLOS model of radio waves propagation ( Non Line of Sight). Application of such a model created certain problems for the standard creators, the most important one being extension of reach of the system. Given lack of optical visibility, multiway propagation takes place, which means that many various signals reach the terminal, signals with various delay times, disturbed signals and with polarity different than in the direct signal. These phenomena cause a considerable decrease of the received power. That is why, in order to improve the system parameters, a number of solutions such as those presented below was applied:

OFDM (Orthogonal Frequency Division Multiplexing): It is a multiplexing technique in which every data portion is sent on a separate available subcarrier, into which the available spectrum is divided, i.e. the data stream is divided into many parallel smaller sub-streams. The subcarriers, each of which transmits one sub-stream, are orthogonal towards each other. In other words, they do not disturb each other despite the fact that they overlap. This solution is resistant to multiroad propagation and in case of degradation of one of the subcarriers, the whole data stream is not lost, only the part transmitted on the given subcarrier. Basing on OFDM, a whole OFDMA method can be created, used optionally in the upward connection, in which every user is allocated with a specific number of subcarriers out of the total number of subcarriers for transmission.
Division into sub-channels: such division is optional in the upward link. Without the division into sub-channels, construction of price-effective terminals would be difficult to realize. For example, if the terminal wanted to transmit in the same way as the base station, then it would require great power amounts and complex broadcasting systems which would result in higher expenses. Reduction of terminal`s transmitter`s power to ex. 25% of the base station transmitter`s power can be achieved in two ways: either by using all of the subcarriers and reducing power of each of them by 75% or by using division into sub-channels, i.e. transmit on every fourth subcarrier with the same power as the base station. Both solutions require the terminal to transmit with equal power. The second solution is obviously far better and its only drawback is fourfold reduction of the upward link`s speed. However, thanks to this, the terminal may transmit with far lower power than the base station and therefore, its costs decrease.

Application of aerial techniques:
- AAS: such aerials make it possible to direct the aerial beam in a given way. During the signal transmission light from the reflector may be directed at a given user. During the transmission, AAS can direct beams only in the direction from which the transmission comes.
- MIMO: application of numerous aerials for signal transmission at both ends of the radio connection (i.e. in the terminal and in the base station). This contributes to considerable speed increase.
- Adaptor modulation. This technique consists in the choice of the right modulation, depending on the distance between the terminal and the base station. The greater the distance, the more susceptible the signal is to degradations. Therefore, modulations more resistant to disturbances are used at the expense of lower transmission speed.
Others:
-Separation of transmission and receipt
-Proper detection and transmission errors correction techniques
-Power steering

VOICE OVER IP-INTERNET TELEPHONY
VoIP (Voice over Internet Protocol) is a technology used for sending sound via network based on IP protocol, which is e.g. Internet. It allows for integration of telephony and data transmission into one net thanks to treating sound as an ordinary stream of data. This technology is more and more often perceived as an alternative to casual telephone networks due to its numerous advantages. VoIP enables making phone calls also to subscribers who do not have Internet and use traditional telephone network or a mobile.

The basic principle of the technology\'s operation is relatively simple, namely the speech signal is transferred to digital representation, it undergoes compression with a proper codec and then it is divided into packets and sent via IP protocol. Many new technologies are used here, including logical elements and special protocols. Logical elements are necessary for, among others, managing notifications and storing information on it, routing packets etc. New protocols are mainly signal protocols, which means that they are used for making connections and multimedia sessions, determining user\'s location, translation of addresses, negotiations of parameters of the notification link, disconnecting and managing notifications, billings and realizations of safety mechanisms. At present two main protocols are used for VoIP, namely H.323 and SIP.

H.323 Protocol
The first version of the protocol was adopted over 10 tears ago, namely in 1996, the second one in 1998. It belongs to the family of H.32x protocols, which describe multimedia connections inside various networks:
H.320 - narrow-band digital networks ISDN
H.321 - broad-band digital networks ISDN and ATM
H.322 - packet networks with guaranteed band
H.323 - packet networks with no guaranteed band
H.324 - analogue POTS networks

All of these protocols support various sets of audio and video codecs, depending on the band made available in the network. They can operate with transmission control (TCP) or without it (UDP), where in VoIP connections no control protocols are used due to additional delays. H.323 supervises the process of sending multimedia data in packet networks, performing this task in real time. Components of H.323 precisely define how particular components of the system, operating according to the protocol, initiate multimedia sessions and how working posts exchange compressed audio and video data between themselves. H.323 supervises processes of sending multimedia data in packet networks, performing this task in real time. Architecture of telephone IP network, base on H.323 standard, consists of four basic elements: terminals, gatekeepers, gateways and MCU (Multipoint Control Units).
Terminals are clients who have the possibility of initiation and receiving notifications. They are also used for sending and receiving two-way stream of data. A terminal can be both, software operating on a PC and a special device designed for this purpose. All terminals should make carrying out a telephone conversation possible, while data or video service is optional.
Gatekeepers manage the so-called zone, which is a collection of terminals, gateways and MCU. H.323 standard divides the net into these zones. Notifications inside a net are managed by a gatekeeper. Inter-zone notifications can engaged many gatekeepers. A gatekeeper, when present in the net, supervises the course of all telephone conversations carried out in a zone. Its basic tasks are the following: control of the available band, routing notifications, receiving, refusing notifications in a zone, translation of addresses and user authorization. Gatekeeper is also an interface to other H.323 networks. A \"gatekeeper\" is an optional element of the network but if it is present in a given subnetwork, then the terminals can use it.
A gateway is responsible for connecting the telephone IP network to other types of network. For example, a gateway can connect H.323 network with SIP, PSTN (Public Switched Telephone Network) or ISDN networks. The gateway must provide an interface of real time between various transmission formats and communication procedures. Moreover, it is responsible for establishing and disconnecting connections in both connected networks. The gateway must therefore have mechanisms converting various formats at its disposal and it must operate networks based on various technologies. MCU runs conferences in which at least three end points participate. An MCU unit manages conference resources, runs negotiations between end points (agreeing on, for instance, the method of encoding audio and video data) and it can steer streams of packets containing multimedia data. MCU consists of two basic elements: Multipoint Controller (MC) and optionally a few Multipoint Processors (MP). MC is responsible for exchange of information and for negotiation of communication parameters between the end points, it runs H.255.0 signaling MP is among others responsible for mixing various multimedia data, format translations and eventual redistribution of streams from users.

What is very often possible is integration of network elements in one physical device. For example, functionality of a gatekeeper can be combined with functionality of a gateway and an MCU or an MCU can be built into the terminal so as to make conference connections possible without additional devices.


LINUX ROUTER FOR SMALL ISP
Everything takes place in Linux environment (distribution practically does not matter but personally I recommend Slackware). I presume that people reading this article are equipped with basic knowledge on compilations, patching and software installation in Linux systems and that they are familiar with basic principles of working with packet filter iptables and a tool for queuing tc. The following elements influence the system so that it manages the band properly:

- linux kernel in version 2.6.15.x
- patch to linux kernel -2.6.14-imq6.diff
- patch to kernel esfq-kernel.patch
- latest iptables (1.3.5 currently)
- patch for the iptables iptables-1.3.0-imq1.diff
- ipp2p module for iptables
- packet iproute2
- patch for iproute2 esfq-iproute2.patch

I suggest installation of the software in the above-stated order. Kernel 2.6.x is much more stable than series 2.4.x. The above configuration was tested by me on a big group of routers (10 ) and it has been working perfectly well. Needles to say, in Linux, you can only limit the output movement from a given interface with tc (Traffic Control). What we need then is a virtual mediation interface (the so-called IMQ) to which the Input movement should be redirected (the so-called Input). Thanks to such an operation, the input movement could be limited as output movement from a virtual IMQ. Obviously, queuing of solutions can be done without IMQ but I do not recommend this method because it is based up feigning packets, which makes later classification and prioritization impossible. I need to say a few more words on the interfaces. No network card based on Realtek\'s chipset should be used (especially RTL 8319), as they are devices designed for working posts and they lose work stability when there are more connections, which is manifested in an increase of the \'pings\' and in many other awkward phenomena. Instead of them I recommend cards based upon Intel Pro or 3com.
Another aspect is the ESFQ mechanism (Enhanced Stochastic Fair Queuing) for the WAN router. In comparison to the traditionally used SFQ mechanism, it enables just division of links with a view to connections from the source and target address (hash src, hash dst - upload, download to WAN). Thanks to this, we are able to make WAN interfaces totally independent from LAN interfaces. Briefly speaking - no queuing is necessary for LAN, the whole movement will be justly separated between them. All of the above solutions refer obviously to HTB mechanism (Hierarchic Token Bucket).


Information Technology in Education, effects of the continuing developments in information technology (IT) on education. The pace of change brought about by new technologies has had a significant effect on the way people live, work, and play worldwide. New and emerging technologies challenge the traditional process of teaching and learning, and the way education is managed. Information technology, while an important area of study in its own right, is having a major impact across all curriculum areas. Easy worldwide communication provides instant access to a vast array of data, challenging assimilation and assessment skills. Rapid communication, plus increased access to IT in the home, at work, and in educational establishments, could mean that learning becomes a truly lifelong activity—an activity in which the pace of technological change forces constant evaluation of the learning process itself.



References:
http://en.wikipedia.org/wiki/Internet
http://www.speedtest2.com/