In Multicasting, the information is sent to only the destined recipients.   It is like the TV or radio transmission system in which only those terminals receive the information who have tuned themselves to receive it.

It is the bandwidth-conserving technology that reduces the traffic load over the network.  The ideal applications that uses the multicast technology includes video conferencing, stock quotes, distance learning, weather updates, video streaming, news and other distributed software applications in the LAN/WAN network.  IP multicasting mechanisms depends upon the two protocols i.e. group management protocol and the routing protocols. 

Group Management protocols establish the multicast groups and the routing protocols routes the traffic to the destination. Multicast routing protocols makes the distribution tree for the data forwarding in the network. It is an ideal solution for the distribution applications in the TCP/IP based LAN/WAN networks.

Though it has been successful in many businesses but it is not extensively deployed and used by the average users.  Special addressing scheme is assigned while implementing the IP multicasting.  These addresses are assigned from the Class D i.e. 224.0.0.0 to 239.255.255.255.  The typical multicast applications include the following.

• For better bandwidth utilization.
• Less Router/Hosts Processing.
• When sending the same data to the multiple receivers is required.
• When the recipient address is unknown.
• When a one-to-many communication systems model is required.

• Enhanced performance.
• Optimized performance.
• One-to-many communication system.

1. IEEE 802.11.
a. 802.11a
b. 802.11b
c. 802.11g
2. HiperLAN/2.
3. Bluetooth.
4. HomeRF
5. Infrared

Wide Industry support, the operating system support, easy installation and the flexibility has made the WLAN a popular choice of the business and home users.  There are different vendors that are manufacturing the various WLAN products.  The major vendors include Cisco, Lucent, Motorola, 3Com, Apple, D-Link and Nortel etc.
There are the many standards in the WLAN and the most popular standard are Wi-Fi and HomeRF.

Advantages of WLAN

WLAN provides numerous benefits to the home and corporate users. Some of the key benefits include the following.

• WLAN technologies can be used to create temporary network for a specific period of time.
• It provides the access to the internet at the public places.
• WLAN can be a part of an existing network and it can connect two physically different networks (in two separate buildings) be establishing a wireless link.
• WLAN technology is a perfect solution for the places where wired network is not possible.
• It provides the mobility, scalability, flexibility and the ease of management.
• WLAN can coexist with the wired Ethernet networks.
• Wireless networking is supported by different wireless standards like 802.11, 802.11b, 802.11a, 802.11g, 802.11n and the 802.11g is the most popular WLAN standard.
• WLAN provides the more productivity, expandability, convenience and the easy deployment at very low cost.

PayPal

PayPal is the largest online payment network. PayPal provides the free and instant online payment service to the selected countries. It is the preferred payment system for the buyers and sellers throughout the world. After getting an account with the PayPal you can send and receive payment online to everyone on your email address.  It is headquartered in California, USA and was founded in 1998.  Through your PayPal account you can transfer your money to your bank account or your credit card.  The PayPal supports different currencies like USD, JPY, CAD, NOK, EUR, SEK, GBP and DKK etc.

2CO

2CO is an excellent payment processor system that enables you to sell your products online or buy products and services online.  It supports thousands of the products to be sold online.  After making account with 2CO, you get robust account management, multiple shipping options, support several currencies and automate the online shopping.  2CO is also known as 2Checkout and it supports more countries than the PayPal.

WorldPay

WorldPay is the leader in the online payment processing systems.   It facilitates the customers to accept the payments via internet, email, phone and fax.  It has variety of payment methods and support multiple currencies and countries.

MoneyBookers

MoneyBookers is another excellent payment method and everyone from the supported countries can join it for free.  After getting account with the Money Booker, you can fund your account, send money online at the receiver’s email address, shop online and receive money.  With MoneyBookers you can send and receive the payment in seconds. It supports local currencies in approximately 30 countries.  There is no setup cost and it accepts almost every major credit card.

E-Gold

E-Gold is a digital gold currency and it allows you the trade or transfer the ownership of the gold between the users.  It is an account based payment system that enables the people to trade or uses the gold as money. E-Gold is used for the payrolls, bill payments, e-commerce, business-to-business payments, person to person payments and donations.

Security Risks and Safety Tips

While these payment processors have made the payment systems easier for everyone but there are some security concerns that can’t be compromised.  There are many security risks are involved in the online payments if your system, email address, merchant account are the e-commerce site is unprotected.  First you need to protect your system against the hackers, spyware, adware, malware and the intruders.
 Install an up-to-dated antivirus, anti spyware and firewall to your system.
Update your operating system with the latest patches and hot fixes.  Never do a purchase from the untrustworthy e-commerce websites.  Check the authenticity, user’s feedback about that particular shopping website.  Never send your sensitive information such as credit card numbers, bank accounts details and other sensitive information to anyone via emails. Use secure browser’s with https requests and make sure that the e-commerce website supports SSL (secure socket layers). In case of any misuse, immediately contact your credit card issuing company or bank.

By using the RIP as gateway host computer sends its entire routing table (that contains the information about all the hosts) to the nearest host.  The nearest host sends this information to its nearest host and so on.  In this way all the connected hosts get updated with the latest information.  RIP is useful for the small networks and it has considered as obsolete as it has been replaced by other protocols such as OSPF (Open Shortest Path First) and IS-IS. 

RIP sends the routing update messages to the adjacent hosts at the regular intervals.  When a router receives some information that includes some changes it updates it’s routing table to reflect new changes. 

After a router updates itself with the latest changes or information it frequently sends this updated information to the adjacent routers till all the routers gets updated.   It supports maximum 15 routers/hopes in a network and it is considered as the best solution for the small homogeneous networks.

It uses the hop counts to measure the distance in the networks.  Every RIP router sends updates to the next hops after every 30 seconds.

It runs at the network layer of the OSI layers model.  A standard RIP packet includes the version, route tag, IP address, subnet mask, next hop and the command.  Configuring a Cisco Router for RIP requires few configuration steps.

You need to enable the RIP routing protocol on the Cisco router and identify the network. The basic RIP configurations on the Cisco router include the following commands.

As a network administrator you need to deal with the security related issues in your network such as patch management, assessing security vulnerabilities, network auditing, services management and network monitoring. 

To detect the vulnerabilities in your network, you need an excellent scanning tool.  Following list provides the best network scanning tools.

GFILAN Guard Network Security Scanner allows you to detect, assess and troubleshoot and vulnerabilities in your network.  Being a network administrator, you often need to deal with multiple security related issues and GFI LAN Guard Network Security Scanner provides you the solution for multiple security vulnerabilities and threats.

GFI LAN Guard NSS scans the network based on the 15,000 known vulnerabilities.  It allows you to scan your networks across multiple platforms.  It provides the customized report of the scans across your whole computer network.

Advanced IP Scanner 1.5  
Advanced IP Scanner is a fast LAN scanner for the Windows based computers.  With this software you can have the detailed information about your network computers in a very short time.  It provides you the multiple functions such as remote shutdown, wakeup and others.  It can scan hundreds of computers in a very short time.
Soft Detect Network Scanner is aimed to scan your computer and find the P2P programs and media files, illegal music, and ensures that no illegal files and programs will be downloading and saved to your computer.  It limits the access to the certain illegal sites from your computer and automatic scans your computer for the potentially dangerous music, media and video files.
It is a very fast security scanner and provides you the multiple options such as scan dead machines, check open ports, scanning multiple ports and the ability to resolve the host names.

Lossless

In the lossless compression technique, the restored data is identical to the original.  This technique is must the data types such as word processing files, executable code, numerical values and the database entries.  In this technique a single misspelled word or numerical value is not affordable.

Lossy

In the Lossy technique, the compression allows some sort of degradation and noise. In this technique, the data files do not kept in the perfect condition for the storage.  The transmissions in the lossy technique contain the certain amount of noise. 

The higher compression rate adds more noise to the data.
By default Windows allow you to covert the files and folders if these are formatted with the NTFS file systems.  There are many third party software that let your files, folders, audio, video and images compress into smaller sizes. The most common compression software are WinZip and WinRar. 

Files that are compressed with these tools have extensions .zip and .rar.  These files can be decompressed by using the same tools at the other end.  The files that are very large even after compressing can be divided into smaller pieces and these pieces of the same files can be reunited at the other end. 

Most of the compression software can support multiple data types like .doc, .pdf, .wav, .mpeg, .jpg, .avi, .gif and others.

TP

FTP stands for the files transfer protocol and it is used to send and receive the files over the IP based networks such as Internet.

SMTP

SMTP stands for Simple Mail Transfer Protocol and it is used to send the email messages to the recipient’s email address through the SMTP server.

DHCP

DHCP stands for Dynamic Host Configuration Protocol and it is used to assign the IP addresses and TCP/IP configurations to the network computers dynamically.

HTTP

HTTP stands for Hypertext Transfer Protocol and it is used to send the requests for a web page to the web server where the web page is hosted.

LDAP

LDAP stands for Lightweight Directory Access Protocol and it used to communicate with the Active Directory in the TCP/IP network.

POP3

POP3 stand for Post Office Protocol and it is used to receive the emails from the email servers.

Telnet

Telnet is a TCP/IP utility that is used to configure, troubleshoot and manage the remote computers and servers.

PPTP

PPTP stands for Point to Point Tunneling Protocol and it used for the secure communication in the Virtual Private Network.

RIP

RIP stands Routing Information Protocol.  It is a single vector routing protocol.  In the vector routing protocols the routers exchanges network information with each others.
                                                              
SNMP

SNMP stands for Simple Network Management Protocol and it is used for the network management.

TFTP

TFTP stands for Trivial Files Transfer Protocol and it is a very simple files transfer protocol.  It is very close to the FTP but it lacks the authentication mechanism.

OSPF

OSPF stands for Open Shortest Path First Protocol and it used to find the shortest possible path from one router to another in a network.

They are easy to administer and provide two way communications.  Moreover the VOIP technology provides the following benefits.

• With this technology you will never miss your important calls.
• You can make long distance calls at very cheap rates.
• You can manage your VOIP account online.
• It’s very easy to setup and make calls with your computer or VOIP device.
• Three-way calling.
• Call waiting.
• Anonymous call block.
• Voice mail.
• Advanced Call forwarding.
• Call Transfer.
• Directory Assistance.
• Conference Calling.
• There are many other value added services.

Due to the limitations, costs and other effects the voice software are only being used in the specialized situations like when a user is unable to use the keyboard to enter the data, in transcribing the medical data or legal data or when the hands are occupied with some other tasks.

The usage of the voice recognition software includes dictation, pronunciation, transcription, court reporting, hands free computing, automatic speech recognition and mobile telephony.

By default Windows XP and Windows Vista let you allow to interact with your computers via voice.  It has been designed for the users who want to minimize the use of the keyboard and the mouse.  It uses the Microsoft Speech Technologies and with this software, you can fill out the web forms, dictate emails and documents, control operating system and switch between the applications.  It provides the following key features.

Commands allow you complete the tasks and naturally control the applications.

It dictates the document and the emails.

It fixes incorrectly recognized words.

It easily resolves the ambiguous situations.

You can say that How Do I followed by a specific tasks like how do I open a file etc.

Dragon NaturallySpeaking 9 Preferred is able to directly dictate into the Microsoft Word.  It can support unlimited number of users, text to speech, hands free mouse pointer controller and MMX technology.

IBM ViaVoice is voice recognition software that includes the command and control features.  With IBM Via Voice software you can record, edit, correct and format the text with the IBM ViaVoice speech-enabled word processor.  It can be customized to add new words, acronyms and other personal phrases and expressions.

It allows you to add, subtract and multiply by voice.

Philips FreeSpeech 2000 is dictation software that is used to dictation in the Word, Corel Draw, Lotus Notes and Eudora.  It uses the voice macros for speedy work.  It can dictate in Spanish, German, Dutch, English, French and Italian.

It is complete voice recognition software and a complete input/output system that provides the accuracy or more than 98%.  It is an ideal word press for the many environments and situations.  It provides the DOS for use with IBM AT and 80XXX.

MacSpeech Dictate is a premier speech recognition solution for the MAC operating systems.  It supports the Microsoft Word, Photoshop, QuarkXpress. It also works with the other MAC applications like ichat, mail, iphoto and keynote etc.  MacSpeech Dictate provides the ultimate and powerful experience for the MAC users.

Ethernet is the most commonly used technology and a standard for the Local Area Network.  Ethernet enables the computers in the local area network to communicate with each other via network cables such as UTP/STP and fiber optic cables. Gigabyte networking involves the fiber optic cables, connectors and gigabyte Ethernet supported LAN cards.

Gigabyte networking is used to provide the very high data communications speed over the fiber optic cables in the Local Area Network. The reference model of the Gigabyte technology is defined by the IEEE. It is a physical and data link technology. There are three types of the Ethernet.

10-Mbps

It is most commonly used for the LAN.  Cable specifications include the following.

10Base-2
10base-T
10base-F
10base-FL
10base-FB
10base-FP

It is also known as 100base T. It uses the RJ 45 connectors in the star topology and it uses the CSMA/CD media access. It supports the maximum number of the connected segments up to 1024. It provides the speed up to 100Mbps.  It is also known as the Fast Ethernet.  Fast Ethernet supports all Ethernet frame types and software and provides better speed than the traditional Ethernet.   It provides better bandwidth and supports more users in the LAN.  It provides 10 times more performance and efficiency than the traditional Ethernet. It is the best for the companies that require fast data transfers and communications. 100base T has the following sub categories.

100base TX
100base FX
100base T4

It provides the speed up to 100Mbps. Gigabyte Ethernet enable the data to travel over the optical and network cables.  Gigabyte networking involves the communications over the fiber optic cables. It provides many times better performance than the traditional Ethernet and Fast Ethernet. It uses the specialized connectors for the fiber optic cables.  Gigabyte Ethernet cables specifications include the following.

There are number of manufactures like 3Com, Acer, Asus, Belkin, Cisco, EXTREME networking, D-Link, Intel, Lenovo and Xerox etc. that are developing the gigabyte hardware products. Gigabyte Ethernet hardware includes the following.

It lets you identify the defective cable in your computer network. Common types of the network cables that are tested by the cable testers include CAT 3, CAT 5, coaxial, trioxial, twisted pair and fiber optic cables.  A cable tester consists of the following. 

Surveillance is the monitoring of the behavior and activities of the people mainly at the public places, airports, offices, homes and other sensitive areas.  There are immediate needs for the security and surveillance systems in the public and commercial places.  Implementing a video surveillance system is cheap as compared to hiring the security experts to observe the human activities.  Surveillance is a great way of monitoring home, offices and public places.

Surveillance cameras are already being used at the airports, bands, commercial plazas, hotels, embassies and stores as the security tool.   Video surveillance technology is also a great way of patrolling the traffic flow, monitor pedestrian congestions and detects the accidents on the highways. Digital video security system consists of the software and hardware components.

These components collect the video camera information and transmit via fiber optic cable, wireless technologies or over the IP-based networks.  Power and data can be carried over the same cable by using a technique known as PoE i.e. Power Over Ethernet.

• What’s the priority of your surveillance system?
• Do you want to observe the general comings and goings?
• Will the video camera be subject to physical damage?
• How your surveillance system be monitored.
• What do you consider that are your biggest security threats.
• Have you ever had problems of theft?

• Avoid dummy camera.
• Do no record audio.
• Know what you want to see.
• Check warranty of your camera.
• After buying, mount the video camera at the door so that you can monitor everyone is coming and going in/out of your home and office.

Hackers

A hacker is a person who breaks into the computer and network security of the online computer users. Hacking is an act of exploiting the vulnerabilities of the operating system without the user’s notice.

Viruses

A computer virus is a piece of code or a self-replicating, malicious software program that exploit the computer by attacking on it.  Computer viruses are specifically designed to perform a number of harmful effects from annoying to destroying. There are different types of the computer viruses and the most dangerous viruses can crash your computer’s hard disk and motherboard.  A most common way of spreading the viruses is through emails.  A computer once attacked by the viruses can quickly spread the viruses to all other connected computers.

Spyware

A spyware is a privacy invading program that is designed to steal the personal and confidential from the computer users.  Spyware can be delivered in a variety of ways including being attached with the legitimate software.

Adware

Adware is an advertising-supporting program that automatically downloads, displays and performs at the user’s computer who downloads the adware-supported software.

Malware

Malware is malicious software or a program such as viruses and spyware that is designed to damage or disrupt the computer system. The other types of the malware are Trojan horses, logic bombs, popups and spam.

Trojans
Trojan is a destructive program that is contained in the harmless program and gets control of all programs. Like the viruses the Trojan do not replicate itself. Trojan can redistribute itself as the part of the computer viruses.  There are different types of the Trojans like remote access Trojans, destructive Trojans, proxy Trojans, FTP Trojans and denial-of-service (DOS) Trojans.

Phishing
Phishing is an act of tricking someone by emails to steal the confidential and personal information.

Keylogger
A keylogger is a malicious program that is secretly installed on your computer to record the keys that you type on your keyboard.  Keyloggers are used to collect the secret and personal information such as user name, password, credit card information and others.  Once the data is collected it can be transferred to the destination by the variety of ways.

Security Vulnerabilities and Threats

• File sharing applications.
• Instant messaging
• Windows Remote Access services
• Web servers and services
• SQL Injections.
• Weak Passwords
• Outdate antivirus and anti spyware programs.

The above mentioned security risks are the biggest threats for every online user. Following solutions can help you to protect your data, privacy and identity on the internet.

Security Solutions

• Install an up-to-dated antivirus program on your computer.
• Install anti spyware program.
• Install and configure software or hardware firewall on your gateway computer.
• Update your operating system regularly by installing latest security patches and hot fixes.
• Encryption your data while transmitting over the internet.
• Never open an email attachment from the unauthorized source.
• Never download a software program from the websites who has no integrity.
• Do not open any website links that you receive through the messenger programs from known users.

Copper and the wireless technologies are being developed at a rapid pace to meet the challenges of the higher bandwidth.  In the broader scenario, the broadband technologies can be classified into the fixed line technologies and the wireless technologies.

Fixed line technologies depend on the direct physical connection of the subscriber’s like in the DSL and in the cable internet connection.

• XDSL

XDSL uses the existing telephone line infrastructure to provide the high speed data communications.  There are different DSL technologies like ADSL, SDSL and VDSL.  The bandwidth and the speed of the XDSL connection depends on the distance of the subscriber’s premises from the local exchange, the quality of the telephone line, the number of connected users simultaneously.

• Hybrid Fiber Coax: Cable Modem and Cable TV.
• Broadband Power Line.
• Public switched telephone network (PSTN)
• Fiber to Home.
• Narrowband
• Baseband

Wireless broadband technologies refer to the technologies that use point-to-point and point-to-multipoint microwave by using different frequencies in the range of 2.5 to 43 GHz to transmit the signals.

• Microwave Links

Microwave Links uses the fixed broadband systems to provide the high speed data communication. It is a point-to-point wireless communication method which provides the data transmission at the rate of 155Mbps within the range of 5KM.  Microwave links are the best solutions for the computer networking with the lower capacity.

• Wi-Fi (Wireless Fidelity).
• Wi-MAX (Worldwide Interoperability for Microwave Access).
• Satellite
• 3G (3G mobile network).
• MMDS (Multi channel Multi point distributed service).
• FSO (Free Space Optics)

Due to the emerging broadband technologies a lot of internet applications and services such as audio and video streaming, Voice over IP, video conferencing, multimedia applications and the mobile applications are able to provide the high speed data transmission, which is not possible with the dial-up connections.  The ultimate bandwidth capacity, higher data transmission speed, security and the reliability of the broadband network technologies has made them the defacto data communication standards for the home and businesses users.

It uses the single key that both the sender and receiver have.

It uses the two keys a public key that can be used by anyone and a private key that is only used by the recipient of the message.

Cryptography includes the mechanisms such as microdots i.e. merging the words with images and some other ways to hide the secret information.  In today’s computer’s world cryptography is associated with scrambling the plain text into the cipher text and this process is known as the encryption and then converting back the encrypted text into the plain text known as decryption.

There are four objectives of the cryptography.

• Authentication. The sender and the receiver can confirm each other’s identity and the source and the destination of the data.
• Integrity. The information cannot be altered without using the secret keys.
• Confidentiality. The information cannot be read or intercepted except the intended recipients.
• Non-Repudiation. The sender and the creator of the information cannot deny his intentions of creating or sending the information.

There are following four types of the intrusion prevention system.

Network Based IPS:  It is usually a hardware device that sits in the network.

Content Based IPS:  It inspects the content of the network packets to detect and prevent the known network attacks.

Rate Based IPS:  It is primarily used for preventing the denial of service and distributed denial of service attacks.

Host Based IPS:  These are the software based applications that are used to detect the unwanted entry in the network after decryption has occurred.

Following are some of the best IPS products.

IPS is the more provides more security and are more powerful than the firewall solutions.  It not only detects but also protects the network.

Features         

The key features of the IPS include the following.

The Cisco 7600 OSR allows the services providers to create the high speed and value added services to meet the customers’ requirements and for the high speed networks. The services are voice and video convergence, internet based applications and the network-based security.  It consists of 256Gbps switching fabrics and forwarding engine that forwards 30 million packets per second.  

• Very high throughout.
• Multicast capability.
• Low latency.
• Rapid routing.
• Interoperability with the today’s circuit switching network.
• High speed data transmission (at the speed of light).

NAT enabled device such as a router or computer sits between the internet and the local network.  The key advantages of the Network Address Translation have been described below.

It bundles the NAT, DHCP and DNS for smaller computer networks.

Based on your unique business requirements there can different network services can be used.  Common network services include the following and these services are used in different types of the networks like LAN, MAN and WAN.

DNS

DNS stands for the Domain Name System and it is used for translating or converting the domain names into the IP address and IP addresses into the domain names.  DNS servers are used on the enterprise TCP/IP networks and on the internet.

DHCP
               
DHCP stands for the Dynamic Host Configuration Protocol and it is a networking service that dynamically assigns the IP addresses and other TCP/IP settings like default gateway, print server, DNS and proxy server’s settings to all the computers in your network.

FTP

FTP stands for the File transfer protocol and it is used to transfer the files over the internet through the FTP client.

Email

Email is the process of sending the text messages, images and video clips in an electronic form.

Printing

Printing is the process of sending the print requests to the print server.  A print server is a dedicated computer in a computer network and the client computers can be attached with it so that they can send the printing request.

File Server

File Server is a computer server that is used to authenticate the users on the network.

Web Hosting

Web Hosting is the process of storing the websites on a central (massive) computer that is known as a web server.

Video Conferencing

Video conferencing technology is the communication type in who two or more individuals at the different locations of the world can communicate with each other via video.

VOIP          

VOIP stands for the Voice Over Internet Protocol is the network service or technology that is used to implement voice communication between two ore more individuals at the remote locations.  It can also be used to make the long distance phone calls.