LAN (Local Area Network)

Minggu, 03 April 2011

Bandwidth Controller Functions

Bandwidth Controller aims to regulate bandwidth for Internet use, for all the computers on the same network get the same bandwidth. When on a computer network consisting of several computers and use the same Internet network, when no Bandwidth Controller then use the Internet on every computer is uneven. For computers that do Download with a large size computer then the bandwidth will be transferred to computers that are downloading it, while another computer bandwidth will drop the (slowing)

Bandwidth Controller software placement is important, because with this software you can share Internet bandwidth to all computers with the same large (Evenly) so suitable for cafe business.

Controller bandwidth is not the same as Server, Server served only as a gate to open or close the path between the Provider with any other computer (Client), Server can block a client computer to not connect with the Internet, the server can also access a site close to the client computer, so that client computer can not access the site; Examples A server may block for the client computer can not access the site facebook.com. While the server is not able to share bandwidth.

Bandwidth Controller Functions:
Set the download and upload another computer for data traffic.
Priorities for the computer or multiple computers to ccess data on the network or Internet network.
Either block or filter the outgoing and incoming packets on a computer or group in control of both LAN network layer 3 and 7.
Activation limits and priorities for other computers, including activation by a certain time.

Bandwidth Controller can be regarded as limiting the software to another computer or to give priority to other computers can access data for Internet and local data

Bandwidth Controller can narrow or divide the speed of traffic on the network. In fact, this software can limit the maximum speed for another computer that is considered too much use of data traffic. Bandwidth Controller also has some very good features in relation to the needs of traffic within a network line.

Here are some of the ability of Bandwidth Controller:
Providing bandwidth usage limits iternet to multiple computers or computer groups by using the traffic data to the server.
Restrict or divide the traffic speed data such as distribution of the maximum or minimum of bandwidth usage
Restricting the use of Internet access to certain computers.
Set the time using the Internet, you can set the time of internet usage when the computer can use the internet and when the computer can not connect to the Internet.
Giving priority of a protocol such as giving priority access protocol VOIP users.
And the best feature is that it can display a list of computers which uses too much bandwidth, so can an administrator will continue to monitor the activity / activities of other computers on the network LAN.
Even Bandwidth Controller featuring Where a computer is ccess data by showing the connection of the server's IP number in the list of list bandwidth Controller.

The workings of Bandwidth Controller

Bandwidth Controller Software is installed or installed on a computer that has access data outside the network. For example, the computer as a server / gateway or router that uses two cards which ehternet 1 card to the internal LAN connection to connect to a network hub, and a more connected to the Internet network. So that all computer connections to the server computer can be arranged by Bandwidth Controller. Because all roads in and out must pass through the server then Bandwidth Controller can monitor other computers like to see where all the computers are connected, how many connections are made or how much bandwidth used by each computer.

Bandwidth Controller is easy to regulate how much the maximum speed of a computer to download or upload in real time on any computer or computer group. Either a computer or group can be restricted to download or upload speeds through computer servers.

Bandwidth Controller does not require specific software on the client computer and is quite attached to the server computer only. Because Bandwidth Controller organize and capture all data packets passing through the ethernet card. In this way, then an IT staff could have reduced the speed of the internet from one computer without interference from the owner. This is helpful when in a network line there is a staff who are too busy to download and retrieve the Internet data traffic so disturbing other workers in need.

Kamis, 31 Maret 2011

The subnet mask is the term information technology

The subnet mask is the term information technology in the English language that refers to the 32-bit binary number that is used to distinguish the network ID with the host ID, indicating the location of a host, whether on a local network or outside network.

for setting the subnet mask, you specify want to create a subnet with what class. I mean, its IP class. For example:

subnet mask: 255.0.0.0 <--- class A subnet mask subnet mask: 255.255.0.0 <--- class B subnet mask subnet mask: 255.255.255.0 <--- class C subnet mask * Class A subnet can be built as many as 256 x 256 = 65 536, with the total number who could be using that computer's IP on the network is 16,387,064 class A IP address. * subnet a class B subnet 256 can be constructed, with the total number of IP a computer on the network is 64 516 class B IP address. subnet mask IP addresses that follow. # IP address Setting up the IP address where mao IP class (A, B, C). For computer network with computer sum <256 computers, better IP pk class C. Saving network resources. NB: To check the configuration of IP address, subnet mask, gateway, open a command prompt, type "ipconfig". IP Address Subnetting Class A

Subnetting a class B IP address

Subnetting Class C IP Address

A subnet mask is usually expressed in dotted decimal notation (dotted decimal notation), as well as IP addresses. After all bits set as the network ID and host ID, the 32-bit value will be converted to dotted decimal notation. It should be noted, that although represented as a dotted decimal notation, the subnet mask is not an IP address.
Classes address Subnet mask (binary) Subnet mask (decimal)
Class A 255.0.0.0 11111111.00000000.00000000.00000000
Class B 255.255.0.0 11111111.11111111.00000000.00000000
Class C 255.255.255.0 11111111.11111111.11111111.00000000

Representation of prefix length (prefix length) of a subnet mask
Classes address Subnet mask (binary) Subnet mask (decimal) Length Prefix
Class A 255.0.0.0 11111111.00000000.00000000.00000000 / 8
Class B 255.255.0.0 11111111.11111111.00000000.00000000 / 16
Class C 255.255.255.0 11111111.11111111.11111111.00000000 / 24

Determining the Network address Identifier
P lamat 10000011 01101011 10100100 00011010 (131107164026)
Subnet Mask 11111111 11111111 11110000 00000000 (255255240000)
-------------------------------------------------- ----------------
Network ID 10000011 01101011 10100000 00000000 (131107160000)

Network Topology

Network Topology is, things that explains the geometric relationship between the basic elements making up the network, namely nodes, links, and station. Network topology can be divided into 5 main categories as below.

1. Bus Topology

This topology is the initial topology in use to connect computers. In this topology each computer is connected to a long cable with multiple terminals, and at the end of the cable must end with a terminator. This topology is rarely used in ordinary computer network because it has some shortcomings such as its probable collision data stream, if one device is broken or there is damage to one part of the computer network will not work immediately before the damage is solved.

This topology was originally used as a medium cable Coaxial introduction of data and information. But at this point in building this topology in computer network using fiber optic cable (fiber optic) but combined with other network topology to maximize performance.

2. Ring Topology

Or ring topology is often called a ring topology is a network topology where each computer connected to make a circle. With a sense that every computer that is connected into a network of inter-connected to two other computers to form a similar network with a ring.

The advantages of this topology is the cable used may be more savings. But the shortcomings of this topology is the network expansion will be difficult because every computer will interconnect.

3. Token Ring Topology

This topology is similar to the ring topology but making more in perfected. Can be viewed from the difference image.

In the picture clearly shows how the token ring connecting cable made a circle first and later will make terminals on each computer and other devices.

4. Star Topology

Or star topology is more often called a star topology. In this topology we have used the help of other tools to connect your computer network. Examples of tools in use here is the hub, switch, etc.

In one picture is clearly seen to function as a central hub connecting the computers that are interconnected. The advantage of this topology is very much at all of them easier to manage network admin, allows the addition of computers or terminals, ease of detecting defects and errors in the network. But with its many advantages in terms of topology this is not without flaws. Shortcomings include waste of cable, which centered on the hub of control sometimes so critical problems if in case of damage to the hub, then all the networks will not be in use.

5. Tree Topology

Topology tree or hierarchical topology also called and could also be called multilevel topology is the topology that can be used on the network in the storied office.

In the picture we can see the relationship between one computer to another computer with a branching hierarchy clear. central center or who are at the very top of an active central central while underneath is a passive central.

Jumat, 14 Januari 2011

VoIP voice quality is influenced by several parameters

Voice over Internet Protocol (also called VoIP, IP Telephony, Internet telephony or Digital Phone) is a technology that allows voice conversations remotely via the Internet. Voice data is converted into digital code and transmitted over the network which sends packets of data, rather than through traditional telephone analog circuits.

VoIP voice quality is influenced by several parameters: capacity bandwidth, packet loss and delay has occurred in the network. Bandwidth capacity is the availability of network resources in the form of bandwidth used to transmit data packets. Packet loss is a parameter that states the rate of errors that occurred during packet data transmission path from sender to receiver. Time delay is a parameter stating the timeframe required to send packages from sender to receiver.

One of the available VoIP applications is Skype. Skype is a [[software]] IP-based voice communication application via the Internet among users of Skype. When using Skype, the Skype users who are online will find other Skype users and began building a network to find other users. Skype has a variety of features that can facilitate the users. Skype is also equipped with SkypeOut and SkypeIn which allows Skype users to communicate with conventional telephone users and mobile phones.

Skype uses the HTTP protocol to communicate with the Skype server to authenticate the username / password and registration with the Skype directory server. Modified version of the HTTP protocol used to communicate with other Skype clients. The advantage of this application is owned by the availability of security services in the form of voice data transmission. Security services provided are as follows:
Privacy

Skype uses AES (Advanced Encryption Standard) 256-bit encryption key with a total probability experiment (brute-force attack) by 1.1 x E-77 times, while for the key exchange (key exchange) simetrik using 1024-bit RSA . User's public key to be certified by Skype server at login using 1536 or 2048 RSA certificate-bit. Skype automatically encrypts all data before it is transmitted over the Internet.
Authentication

Every Skype user has a username and a password. And each username has an e-mail address registered. To enter the Skype system, users must include a username and password pair. If users forget their password then Skype will change it and send the new password to your e-mail users who've registered. This approach is known as E-mail Based Identification and Authentication. Because Skype is a voice communication system, each user can directly identify his interlocutors through the vote.

VoIP Benefits
Lower costs for direct dial long distance. The main emphasis of VoIP is cost. With two locations that are connected to the internet then the conversation becomes very low cost.
Infrastructure utilizing existing data networks for voice. Useful if the company already has a network. If possible the existing network with a VoIP network can be constructed easily. Not required additional monthly fee for the addition of voice communication.
The use of smaller bandwidth than a regular phone. With the rapid advancement of technology, the use of bandwidth for voice had now become very small. Data compression technique allows voice only need about 8kbps bandwidth.
Allows combined with local phone network that already exists. With this form of VoIP network gateway can be connected with existing office PBX. Communication between the office can use a regular telephone
Various forms of VoIP networks can be merged into a larger network. The example is VoIP Rakyat Indonesia.
The variation of the use of existing equipment, eg from a PC connects to a regular phone, IP phone handsets

Weakness of VoIP
The sound quality is not as clear as the PSTN network. Represents the effects of voice compression with a small bandwidth then there will be reduction in sound quality compared to the conventional PSTN network. But if the internet connection used is broadband internet connection / broadband such as Telkom Speedy, it will be crystal clear sound quality - even more clearly than Telkom connections and not to falter.
There was a pause in communication. The process of changing data into sound, network lag, making the gap in communication by using VoIP. Except if you use a broadband connection (see point above).
Regulation of the Government of Indonesia to limit the use to be connected to a network owned by Telkom.
If not connected to the internet 24 hours to promise to be interconnected.
If using the internet and computers behind NAT (Network Address Translation), it takes a special configuration to make it run VoIP
There is never a guarantee of quality when VoIP through the internet.
Equipment is relatively expensive. VoIP equipment that connects between a VoIP PBX (IP telephony gateway) are relatively expensive. It is expected that with the popularity of VoIP is the price of the equipment will also start down the price.
Potentially cause tissue obstructed / Stuck. If the use of VoIP is increasing, then there is the potential of the existing data network to be full if not managed properly. Bandwidth settings are necessary for the company's network does not become saturated due to the use of VoIP.
Surviving without a coordinated network properly will cause chaos in the numbering system
[Edit]
Community VoIP

Community of users / developers of VoIP in the community, developed in 2000. Community early users / developers of VoIP is the "VoIP Merdeka". "VoIP Merdeka" (VM) is triggered by Onno W. Purbo. The technology used by the "VoIP Merdeka" (VM) is H.323 which is the beginning of VoIP technology. Central VoIP Merdeka in hosting in Indonesia Internet Exchange (IIX) for the support of some ISPs and Asossiasi Internet Network Operator (APJII). Area code "VoIP Merdeka" at that time unanimously determined to be 6288, of course without obtaining approval from the government.

In 2005, Anton Raharja et al of the ICT Center Jakarta began to develop new types of VoIP-based Session Initiation Protocol (SIP). SIP technology is a replacement technology is difficult to penetrate H.323 proxy server. In 2006, SIP VoIP infrastructure, known as VoIP Rakyat

Fiber optic cable is one type made of glass or plastic

Fiber optic cable is one type made of glass or plastic kind that are very smooth and smaller than a hair, and can be used to send light signals from one place to another. The source of light used is typically the laser. The cable is approximately 120 micrometers in diameter.

The development of fiber optic cable technology to date, have been able to generate attenuation (attenuation) of less than 20 decibels (dB) / km. With a track width (bandwidth) is large, so the ability to transmit the data become more and faster compared with using conventional cable such as UTP cable. Thus the fiber optic cable is suitable for use primarily in applications of data telecommunications systems. In principle, the fiber optic cable to reflect and refract some light propagating within it.

The efficiency of fiber optic cable is determined by the purity of the building blocks of glass. The more pure glass material, the less light is absorbed by the fiber optic cable.

Fiber optics is the most advanced media in terms of data transmission.
Cable FOR (fiber optic cable) made of glass wrapped in a protective skin that serves as a protector of a fragile glass FO.
Mode fiber optic cable consists of single mode and multi mode, which distinguishes the two is from the diameter glass fiber optic cable. The fiber optic patch is usually used as a liaison with the media converter. Fiber optic cable termination techniques exist that use glue technique apoxy fiber optic termination and splicing techniques. What distinguishes multimode fiber cable and multimode fiber optic is in terms of distance data transmission. Fiber optic cable single mode type can send data farther than the type of multimode fiber cable. For connection to a media converter fiber optic connector is required. Currently fiber optic cable is used to transmit Internet signals throughout the world. Optic optic cables are also widely used in communication media for sensors (fiber optic sensors.)

Terminating fiber optic cable (fiber optic)

Terminating fiber optic cable fiber optic / optical / optical / Optics / optical fiber optic cable.
Termination is in the process of installing a fiber optic connector / optical / Optics / optical fiber optic. This process can not be done arbitrarily, because the diameter of the fiber optic cable / optical / Optics / optical fiber optic is so small, much smaller than human hair.
Required to perform the termination tool kit called the termination kit. Fiber optic connector termination process / optical / Optics / optical fiber optic cable jacket stripping begins with the device known as a stripper, and core optical fiber / optical / Optics / optical fiber optic cut by means Scribe. Further core optical fiber / optical / Optics / optical fiber optic inserted into the connector, then bonded with epoxy glue. After drying, the epoxy will be heated in the oven, next to the optical fiber / optical / Optics / optical fiber optic polished with lapping film. To perform the termination, a terminator must work with precision and care, because the handle is a fiber optic cable / optical / Optics / optical fiber optic is very small, much thinner than human hair.

The process of connecting fiber optic cable / optical / Optics / optical fiber optic cable.
Usually the fiber optic cable / fiber optic / Fiber Optics / optical fiber / fiber optic cable wound on haspel. The length of fiber optic cable / optical / Optics / optical fiber optic cable in a cable haspel depending on the size and haspel. There haspel which can accommodate 2000 m cable fiber optic cable / optic cable / cable Optics / optical cable fiber optic cable.
Because the fiber optic cable / optical / Optics / optical fiber optic cable called for long distance (to reach tens or hundreds of kilometers, it is necessary to process the connection, a process called splicing. Tools to make the connection of fiber optic cable / fiber optic cables / fiber cables Optics / optical fiber cable / fiber optic cable called a fusion splicer.

Progress Technologies Fiber Optic Cable (Fiber Optic):
Fiber optic cable (fiber optic cable) is one type of cable network that could send data packets to hundreds of kilometers through the medium of light. Compared with other types of cable, fiber optic cable (fiber optic cable) is most rapid in tranfer data packet transmission and fiber optic cable (fiber optic cable) can reach more than 100 kilometers.
Experts in the world is hoping to increase the speed and range of types of fiber optic cable (fiber optic cable) this. To be able to create a fiber optic cable (fiber optic cable) this good, the experts continue to conduct research with the most pure glass materials and strive to create a core diameter as small as possible. The smaller the diameter of the core of a fiber optic cable (fiber optic cable), then the fiber optic cable (fiber optic cable) will be able to send data farther and faster. Fiber optic cable (fiber optic cable) are also included types of cables that are resistant to electromagnetic interference which causes the fiber optic cable (fiber optic cable) can send data at higher speeds compared with other cable types. Fiber optic cable (fiber optic cable) does not carry electrical signals, such as other cables using copper wires as UTP cable. Instead, the signal representing the bit is by fiber optic cable (fiber optic cable) is converted into the form of light.

Fiber Optic Cable Can Reach Hundreds of Kilometers:
Until now, experts are still divided over fiber optic cable (fiber optic cable) in two types, namely fiber optic cable (fiber optic cable), known as fiber optic cable (fiber optic cable) and single mode fiber optic cable (fiber optic cable ) multi-mode. Fiber optic cable (fiber optic cable) type single mode can reach a greater distance and only send one signal at a time. While multimode fiber cable capable of sending different signals at the same time, transmit data at a different angle of refraction at the same time. Single mode cable can reach hundreds of kilometers while multimode cable is usually only reaches 550 meters or less to reach speeds 1000MBps.
Connector fiber optic cable (fiber optic cable) consists of many types, there are three types of connectors are most often used to apalikatin world and technology industry, namely fiber optic cable connector ring-shaped ST model, the connector fiber optic cable (fiber optic) models square-shaped SC connector and fiber optic cable (fiber optic cable) square-shaped LC model but small compared with fiber optic cable connector type SC. In applications in the field, the use of fiber optic cable (fiber optic cable) has to be tailored to the needs for speed and distance of the field, of course, must be supported also by the active devices and passive devices in accordance with the type of fiber optic cable (fiber optic cable) is. Active devices and passive devices that do not match the type of fiber optic cable (fiber optic cable) that will be installed, will result in fiber optic networks (optical fiber cable) is not working at all.

Fiber Optic Cables (Fiber Optic) Is the Internet Backbone Network Around the World:
At this present time, fiber optic cable (fiber optic cable) or fiber optic cable (fiber optic cable) has reshaped the information technology industry. It's hard to imagine what might be the Internet network can be developed, as now, without creation of fiber optic cable (fiber optic cable). In the event of a magnitude 7.2 earthquake that shook Taiwan ritcher scale and caused a tsunami that damaged fiber optic cable (fiber optic cable) to the internet and the landing station in Taiwan, a very serious impact on Indonesia's Internet connections, including connections Speedy made through broadband. It is estimated that the entire Internet connection to access Web sites overseas, especially in the U.S. susceptible to interference. From this incident, we came to know, that backbone Internet networks around the world were using a fiber optic cable (fiber optic cable). Imagine if the entire fiber optic cable (fiber optic cable) to a backbone Internet network that connects between the continents was cut off. Yes all internet connections in the world will die completely. Fiber optic cable (fiber optic cable) appeared to provide the greatest role to make the Internet can be used around the world.

Fiber optic cables (fiber optic) was applied to the long-distance telephone technology and industrial automation with remote control:
Fiber optic cable (fiber optic cable) is also applied to long-distance phone technology and industrial automation with remote control.
When the fiber optic cable (fiber optic cable) to replace copper (copper) as long distance calls and internet traffic that indirectly impact on the reduction of production costs. To understand how a fiber optic cable (fiber optic cable) work, for example try to imagine a plastic straw or a length of flexible plastic pipe are large. Imagine the pipe has a hundred yards long and you look inside of one side of the pipe. A hundred yards over there a friend turn on the flashlight and directed into the pipe. By because of the inside of pipes made of glass material is perfect, then the torch light will be reflected on the other hand, although the form of bent or twisted pipe can still be seen the reflection of light at the end. If for example a friend lit a torch light to live and die like Morse code, then you and your friends can communicate through a pipe. Such was the basic principle of fiber optic cable (fiber optic cable) or commonly known as the fiber optic cable (fiber optic cable)

Jumat, 03 September 2010

Local area network providing data transmission

Local area network providing data transmission functions through different types of physical networks. Local area network operates at Layer 1 (physical layer) and 2 (data link layer) in the OSI reference model that works in synergy to carry out the task of forming data communication with a good design of your network environment. For more details, reference the OSI model this problem you can read in more detail in my article the other problems the OSI reference model.

Local area network (LAN) consists of computer, network interface card (NIC), networking media, network traffic control devices, and other network peripheral devices. LAN allows a business office that uses computer technology to share an efficient, such as files, printers, and allows communication of information such as e-mail, telephone VoIP, Skype, and other.

Local Area Network is designed to do the following:
Operate within the limits of geographic areas
Allows any user to access a wide bandwidth media
Providing full-time connectivity to local services
Connecting two adjacent tool-limited cable media / wireless

Local area network consisting of high-speed network infrastrucktur in one single location that is used to transmit application data and other data services. Local area network technology that is widely used on Ethernet technology that is used is because its cheap budget; easy to use and easy in maintenance and its ability to scale up to a Gigabite-speed network.

Any network device that is used on the network infrastructure local area network? network devices that operate at Layer 2 Data Link is the Bridge; Switch and ATM switches. Switch is a switching device is purely working on layer 2 Ethernet which allows more efficient use of bandwidth. This switch devices can localize the impact of the collision (collision) and data contention data (data that were all fighting street - mutually in two-way streets) in a network. This can be achieved by studying the device address (MAC address) dynamically in the local area network and only to deliver a data gram to the address of devices are eligible to receive only - according to the recipient address if the letter is written. What about Bridge? Bridge is the original definition of the functions that can be done by the switch. While ATM ATM switch is a device that has the ability to switch functions. While local area network devices that operate at Layer 1 is the hub or concentrator or repeater.
What are the Design a common local area network?

This above picture is a diagram of local area network with a small scale only consists of several client computer as a data server that also functions as a print server; Wins or even as a control as well. Simple measure of local area network is usually used in SOHO - small office home office.

This above picture is a local area network with medium size which can consist of three or more switches are mounted on one or more networks between buildings. We see that the system redundancy is not applied in this medium-scale networks.

Local area network which can luck far more complicated than the above diagram which is a large-scale local area network where the switch-2 is configuration such a way in a network with redundancy system by activating all the spanning tree protocol on switch-2 is so manual tuning of all switch.

Why none of the three hubs in the form of a series on local area network? Hub is no longer popular today, but more importantly is the reason that the hub is a device that has an ancient network of the most intelligent even though not able to use local area network bandwidth efficiently. For repeater hub that serves as many ports to share a limited bandwidth is shared among all devices connected, and form one collision domain and one broadcast domain - essentially in a single bandwidth. Things like this is what ultimately caused the number of data collision (crash data), timeout in the terminal and also the number of re-transmission of data.

Therefore, all local area network switch which is supposed to use much higher would increase the flow of Ethernet networks and far to reduce the data collision on a local area network. therefore, the following is the standard recommended by the switches used in local area network.
To connect desktop computers to use the minimum speed 100Mbps switch.
Use speed 1 Gigabite switch for server connections or inter-switch connections (up links).
Must support a command line switch for the Telnet utility; ie snmp-based management.
Supports spanning tree protocol.
Supports Virtual LAN (VLAN).
Supports tuning of STP per VLAN protocol.
Supports aggregation technology

VLANs can create a network segment can easily be made for management reasons or reasons of security. VLAN also allows high-density LAN switches are built using the same hardware. Some switches can also connect to each other in a transparent inter-VLAN using VLAN trunking protocol.

In this simple diagram above, the segmentation of local area network using a switch that supports VLANs. In our previous scenario, local area network at the department of Geology, Accounting and Workshop segmented using VLANs.

Selasa, 03 November 2009

Wi-Fi

(Wireless Fidelity) is a wireless connection such as mobile phones using radio technology allowing users to transfer data quickly and securely. Wi-Fi not only be used to access the Internet, Wi-Fi can also be used to create wireless networks in the company. Therefore, many people associate with Wi-Fi "Freedom" for Wi-Fi technology gives the user the freedom to access the Internet or transfer data from the meeting room, hotel rooms, campus, and café-café that marked Wi-Fi Hot Spot. Also one of the advantages of Wi-Fi is practical, not have to bother installing network cable. For the problem depends on the speed of the signal obtained.

Wi-Fi service offered by each Hot Spot vary, some offer free access as well as in airport executive lounges, which requires a user to become one of the ISP subscribers that offers Wi-Fi facilities and there were also offers card pre-paid. Whatever your choice for how to access the Wi-Fi, the most important is the existence of Wi-Fi, you can work anywhere and anytime that you do not need to always be stuck in your office to complete each task Mobile phone market (mobile) or dual mode capable GSM cellular network access and wireless Internet networks Wi-Fi (wireless fidelity) continue to increase. Juniper Research is a research project the dual mode mobile phone market in 2012 reached U.S. $ 68 billion.
Currently demand devices that can facilitate user activity to communicate through a network of voice over internet protocol (VoIP) both from the corporate and consumer continued to show growth.

Wifi uses radio frequency waves to transfer data to be sent are divided into several protocols such as 802.11a, 802.11b, 802.11g and 802.11n is the latest to use in the office and the cafe-cafe is frequently used protocols 802.11a/b/g . Due to transfer using radio frequency waves of data sent can easily be captured dijangkauan user Access Point.

One of the WiFi network security protocol used by the first generation of cafes and offices in general, actually, a wired LAN network more secure because there are no protected structures such as Wifi cable which utilizes radio frequency waves that can be captured by all users who are in the range of Access Point tersebut.dan WEP network is one of the security protocol of the easiest in translucent.

Why are easily penetrated, because the encryption key for this system is a static key using RC4 encryption easily in the crack by hackers who easily stole the data packets are sent over the air by using the tools, free tools scattered on the internet and forums, Wifi discussion forum.