Smart cards

A smart card is similar to a magnetic stripe card but contains a microprocessor chip. The first smart cards were prepaid telephone cards, which operated on stored prepaid values. They have moved on from this to be used for things such as library cards, credit cards, student cards, and electronic purses.

Today, there are three smart card types with different access methodologies.

Contact cards
With a contact smart card, the user inserts it into a reader in order to access the information on it. The data is then transferred once physical contact is made. The reader supplies power to the chip in the card through the contacts. These cards are used in financial applications such as store-value, debit, and credit cards because of their reliability and the high power available to the microchip processor. Contact cards are slower and require more servicing than contactless cards.

Contactless cards
Contactless cards communicate with the card reader using radio frequency technology. They are implanted with a radio antenna. No physical contact is required with the reader. Contactless smart cards are suitable for application in fast paced transactions. Proximity, close-coupled, and vicinity cards are sub-types of contactless cards. Vicinity cards are used in industrial tagging, car-park access, and library book tagging. Contactless cards cannot support encryption techniques and are expensive to manufacture. (more…)

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Mobile IP is becoming more important for the average consumer and for businesses. Mobile IP standards are improving, as are the services offered by service providers. Because of this, more efficient services and applications are available to mobile users. In business, key employees can be kept up to date with critical information, which results in improved customer service and, ultimately, in improved customer relations. Mobile IP allows consumers to communicate and to avail of a variety of services, such as instant messaging and SMS alerts to their cellular phones with, for instance, the latest traffic reports or sports results.

With the development of large open networks – networks with access to the Internet, and other private and public networks – threats to security have increased and more security vulnerabilities have been discovered. The technical knowledge required to hack a network has become more widely available and hacking tools are more user friendly.

Because of the way Mobile IP operates, the transfer of information is vulnerable in terms of security. The registration process in itself is vulnerable because, typically, mobile computers are connected to the network via wireless links. When mobile nodes on foreign networks register with their home networks via wireless links, they are vulnerable to attacks such as passive eavesdropping and active replay. This means that authentication mechanisms in Mobile IP registration need to be particularly strong. For example, service providers need to authenticate messages sent between foreign agents and home agents to ensure only legitimate customers are provided with service and to enable billing.

Threats to Mobile IP

Specific threats to Mobile IP include the following: (more…)

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Mobile IP is a standard communications protocol, developed by the Internet Engineering Task Force (IETF) and designed to allow mobile-device users to move from one network to another while maintaining their permanent IP address.

Mobile IP is an enhancement of the Internet Protocol (IP). It allows for Internet traffic to be forwarded to mobile devices, also called mobile nodes, when they are connecting through networks other than their home network. In wireless computing, Mobile IP is the technology that enables a user to receive information, such as e-mails and files directly to one’s laptop, without the sender’s knowledge of the serving network IP address.

It is predicted that wireless access will soon become the dominant means of connecting to the Internet. As it becomes more common, mobile users will expect similar levels of connectivity and service quality to wireline users, and Internet protocols will need to be further developed to meet the technological challenges ahead. Mobile IP, as it currently stands, presents a problem in terms of performance and scalability. (more…)

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After getting know the router on internet connectivity, there are another Communication technologies that we need to understand was bandwidth.

In analog systems, bandwidth is the difference between the highest-frequency and the lowest-frequency signal components of a transmission channel. Frequency is measured as the number of cycles per second, or Hertz (Hz). In digital systems, bandwidth indicates the data transmission in bits per second (bps), and the standard prefixes are used to indicate values such as a thousand bps (Kbps), a million bps (Mbps) and a billion bps (Gbps).

So bandwidth is a measure of the amount of data that can travel over a communication system in an allotted time frame. It may be referred to as data throughput or line speed. Bandwidth is directly proportional to the rate of communication, meaning that the greater the bandwidth, the faster the communication.

Common communications technologies

There is a wide range of networking technologies in use today. These include cable modems, digital subscriber line (DSL), Integrated Services Digital Network (ISDN), regular telephone lines, satellite connections, and wireless connections. (more…)

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One of the primary purposes of a network is to increase productivity by linking computers and computer networks, so that people have easy access to information regardless of differences in time, place, or type of computer system.

Components of a network

Because companies have adopted networks as part of their business strategy, they typically subdivide and map corporate networks to the corporate business structure. In the figure, the network is defined based on the grouping of employees (users) into a main office and various remote access locations.

A main office is a site where everyone is connected via a LAN and where the bulk of corporate information is located. A main office can have hundreds or even thousands of people who depend on network access to do their jobs. It may have several LANs, or it may be a campus that contains several buildings. Because everyone needs access to central resources and information, it is common to see a high-speed backbone in a LAN as well as a data center with high-performance computers or servers and networked applications.

A variety of remote access locations connect to the main office or each other using WAN services as follows: (more…)

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