What are uses of WiMax technology?

- The WiMax technology has been used since a long time to provide assistance to the communication process.

- This area has seen major deployment of wimax technology especially in Indonesia during the calamity of tsunami in the year of 2004. 

- The WiMax technology brought in the possibilities of providing broadband access that helped a big deal in regeneration of the communication. 

- The organizations such as FEMA and FCC (federal communications commission) felt the need of wimax in their communication process. 

- The WiMax applications with high efficiency are available today.

- It is known to offer a broad base for the customers and the services had been improved by adding mobility feature to them.

- The service providers use the WiMax technology for providing various services such as mobile and Internet access, voice, video and data. 

There are other advantages of using wimax technology.  

- You get to save a lot of prospective cost and at the same time you get efficiency in services.

- It is even capable of allowing the video making, VOIP calling and data transfers at high speeds.

- The mobile community has been upgraded so much with the coming of the WiMax technology.

- However, there are three main applications offered by WiMax namely backhaul, consumer connectivity and business.

- The real augmentation has been drawn to communications through WiMax technology because of which they can benefit both from the data transmission and video apart from voice. 

- This has facilitated quick response from the applications as per the situation.  

- A temporary communication services can be deployed by a client using WiMax technology.

- It can even speed up the network according to the circumstances and events.  

- This has got us access to visitors, employees and media on a temporary basis.  

- If we are located in the range of the tower, it is quite easy for us to gain access to the equipment of the premises of for the events.

The factors that make the wimax technology so powerful are the following:

> high bandwidth

> high quality services

> security

> deployment

> full duplex consisting of DSL

> reasonable cost

For some applications, the wimax technology is used exclusively as in the following:

1. A means of connecting for the small and medium sized businesses.  - This technology has enabled these businesses to progress day by day.

- The connectivity offered by WiMax technology is good enough to attract clients.  

- It then provides them a number of services such as that of hotspots and so on.  

- Therefore, this application has gotten into spot light.

2. Backhaul

- The most important application of the WiMax technology is the range.

- This is so because using WiMax tower can be used as a means to connect with the other WiMax towers through line-of-sight communication which involves using microwave links. 

- This connectivity between two towers is called as backhaul.  

- It is capable of covering up to 3000 miles. 

- The WiMax network is even sufficient for covering remote and rural areas.

3. The nomadic broadband is another application of wimax technology which can be considered as an extended plan of wifi.

- The access points provided by WiMax technology might be less in number but they offer very high security.  

- Many companies use the WiMax base station for the development of the business.

What is WiMax technology?

Worldwide inter-operability for microwave access or wimax is standard developed for wireless communications that has been designed so as to deliver data rates of 30-40 mbps. The update in the technology in the year 2011 upgraded the technology to provide around 1 gbps for the stations that were fixed. 

- The Wimax forum is responsible for naming the technology as Wimax. 

- This forum was formed in the year of 2001 for the promotion of the inter-operability and conformity of this standard. 

- The Wimax has been defined by the forum as the technology based up on standards that enable the last mile wireless broadband delivery as alternative for the DSL and the cable thing. 

- The IEEE 802/ 16’s interoperability implementations are referred to as the WiMax. 

- The wimax forum has ratified this family of standards. 

- By virtue of the certification provided by this forum, the vendors are able to sell mobile and fixed products that are wimax certified. 

- This is done for ensuring that a level of inter-operability is maintained at par with the other products that have been also certified for the same profile. 

- The ‘fixed wimax’ is the name given to the original IEEE 802.16 standards.

- ‘Wifi on steroids’ is the term used to refer to WiMax sometimes. 

It has got a number of applications such as in:

Ø  Broadband connections

Ø  Cellular back-haul

Ø  Hot spots and so on.

- This technology shares some similarity with the Wifi technology however, this one is more capable of transmitting data at greater distances.

It is because of its range and bandwidth that the WiMax is suitable for the following applications:

Ø  Provides services such as the IPTV services and VoIP (telecommunications services).

Ø  Provides mobile broadband connectivity that is portable across the cities and countries and that can be accessed via different kinds of devices.

Ø  Provides an alternative for DSL and cable in the form of wireless last mile broadband access.

Ø  Acts as a source of internet connectivity.

Ø  Metering and smart grids.

- This technology can be used at home for providing internet access across the countries. 

- This has also caused a rise in the market competition. 

- The WiMax is even economically feasible. 

- Mobile wimax has been used as a replacement for the technologies like CDMA, GSM that are cellular phone technologies.  

- The technology has also been used as an overlay for increasing the capacity.  

- The fixed wimax is now used for 2g, 3g and 4g networks as a wireless back-haul technology in almost all the nations whether they are developed or developing.  

- In some states of North America, this technology is provided through a numbered of copper wire line connections. 

- On the other hand, the technology is back hauled via satellites in case of the remote cellular operations.  

- While in other cases even microwave Links are used. 

- The bandwidth requirements of the WiMAX demand more substantial back-haul when compared to other legacy cellular applications. 

- In some of the cases, the sites have been aggregated by the operators by use of Wireless Technology.  

- The traffic is then introduced to the fiber networks as per the convenience.  

- The technologies that provide triple play services are directed compatible with the WiMAX.  

- These services might include multi-casting and quality of service. 

- WiMax has been widely used for providing assistance in the communications. 

- The Intel Corporation has donated the hardware for WiMax technology for assisting the FCC (federal communications commission) and FEMA etc.

- The subscribers’ stations or SS are the devices which are used for connecting to a WiMAX Network. 

- These devices might be portable such as the following:

      > Handsets and smart phones

      > PC peripheral such as USB dongles, PC Cards and so on. 

      > Embedded devices in notebooks.

What is meant by Dynamic Virtual Private Network?

Dynamic virtual private network or DVPN is a network used for interconnecting various virtual application networks. 

- These networks reduce the need for manual configuration by a large percentage (almost by 93 %). 

- Dynamic virtual private networks help a great deal in the simplification of the wide area connectivity spread across a virtual application network.

- These networks have a great complexity when compared to the other networks.

- Further, they prove useful in establishing interconnections between various campuses, data centers, and offices and so on via IPsec VPN encryption. 

- The solution offered by the DVPNs is quite scalable, simple and secure. 

- The dynamic virtual private networks are highly automated and therefore provide a simple management solution. 

- A DVPN can scale up to 1000 – 3000 sites on a single router. 

- All these sites together constitute the domain of the DVPN. 

- So it is obvious that a very large network can be scaled via multiple DVPNs. 

- The best thing about these DVPNs is that they support all the WAN technologies and therefore can be implemented up on all.

- Furthermore, they offer flexibility in reducing the cost when compared to the lower cost broadband access.

- All the network operations are simplified since DVPN has automated VPN setup plus provisioning.

- DVPNs offer high resilience without adding to the complexity of the network. 

- Another characteristic feature of a dynamic virtual private network is its carrier agnostic connectivity.

- One solution to DVPN is offered by HP that has got the following features:

1. Full mesh or hub – spoke configuration
2. Encryption based up on IPsec standards.
3. The control plane and the data plane have been separated to ensure scalability.
4. Up to 30,000 clients are supportable by the VAM (VPN address management) server.
5. Offers zero touch configuration.

- Another solution is offered by the Juniper networks. 

- Juniper’s DVPN is more of a client-less solution and has been designed for ‘remote access’ IPsec VPN. 

- The delivery of the client to the end users is made dynamically from SRX. 

- The remote access is simplified by DVPN since it provides the users the facility to secure the IPsec VPN tunnels without any need for configuring the VPN settings on their systems. 

- This whole process comes in to when the users login to the server’s web site. - Juniper’s DVPN solution can be licensed to 5, 10, 25 or 50 concurrent users. 

- It supports windows xp and above versions (both 32 and 64 bit).

- However, there are certain limitations for this solution:

1. It requires an external RADIUS server for providing an IP address and for XAUTH.
2. Does not support shared IKE id.
3. Mandatory PFS (perfect forward secretary).
4. Requires custom IKE/ IPsec security proposals.
5. Only IKE – id supported is the FQDN.

- Configuration for DVPN is required only on the SRX gateway.

- Dynamic virtual private network is more of an intranet enabler whose purpose is to complement the regular services offered by the internet by adding more services as well as resources to it. 

- One major feature of these networks is that they have an excellent ability of loading balance on – the – fly allocation of the resources. 

- These networks are more popular in businesses since they offer more security by means of packet encryption protocols. 

- Self – modification is possible for the DVPNs and so they are able to recognize the added nodes without help from routers.

- Encryption and authentication are two technologies used by DVPNs for securing packing data and delivering across the networks. 

- Until the data reaches it destination it remains unpacked or encapsulated. 

- For reaching the remote networks tunneling is used. 

How does a simple path segment play a role in data flow testing?

Whenever you have discussed about the data flow testing you must have came across the term simple path segments while discussing about the strategies for data flow testing. Many of us are not quite clear with the concept of the simple path segments and what role have they got to play in the data flow testing. This article is all about the simple path segments and the role that they have got to play in the data flow testing. 

First we shall brief up ourselves with the concepts of the data flow testing before moving on to the topic of the simple path segments and their role. 

What is Data Flow Testing

- Data flow testing includes all those strategies that have been based up on the selection of the paths via the control flow of the program for discovering the sequence in which the events related to the object’s status take place.

- A primary bug assumed during the data flow testing is that though the control flow is generally correct, there is some fault with the software system or application since the data objects are not available when they are supposed to be or weird things happen to the data objects. 

- Even if some problem is found to preside in the control flow of the program it is initially detected by the data flow analysis. 

- One of the most aiding tool in the data flow testing are the control flow graphs which are the graphs consisting of directed links and nodes. 

- The objective of the data flow testing is to discover the deviations in the data flow. Three types of data objects have been defined namely:

1. Killed or undefined
2. Defined
3. Usage

And some nine kinds of anomalies have been defined:

1. dd: harmless but suspicious
2. dk: might be a bug
3. du: a normal case
4. kd: a normal situation
5. kk: harmless but might be containing bugs
6. ku: a bug or error
7. ud: not a bug because of re- assignment
8. uk: a normal situation
9. uu: a normal situation

These anomalies are detected by the means of two anomaly detection techniques namely:

1. static anomaly detection technique and
2. dynamic anomaly detection technique

All the strategies involved in the process of data flow testing are structural. Data flow testing and path testing strategies have so many things in common. But one of difference between them is made by what one takes in to account for testing. Path and data flow testing both are emphasized up on the raw connectivity of the graph but in addition to this the data flow testing also focuses up on what happens to the data objects. There are so many terminologies associated with the data flow testing and simple path segment is one of them. The others are:

1. definition clear path segment
2. loop free path segment
3. du path segment

What is Simple Path Segment

We shall now define what a simple path segment is! 

- Any path in which the same node is visited twice at the most, such a path is called a simple path segment. 

- One can easily make out why a simple path segment is called so! 

- It is called so because it does not consists of loops in both the nodes.

- Only one node holds the loop. 

- One of the problems that are faced by the testers is of finding the simple paths. 

- This problem can be overcome by following a lower bound max- flow approach. 

- The simple path segments though being, are important in the data flow testing just like all the other path segments. 

How is testing done on different smart phones?

The word smart phone is all around us these days! Smart phones are on the verge of becoming the devices with the highest demand.

But what it is that makes a smart phone quite different from an ordinary feature both in performance and appearance? What is its smartness quotient?

To put it simple, we can say that:

- A smart phone apart from just making and receiving calls, grants one extravagant usability by means of many other features like listen to songs, send and receive e mails and edit the documents and so on.

- A smart phone has been made by putting together the features of both the mobile phones and PDAs (personal digital assistance).

- Features of cell phones like making calls and sending messages and PDAs features like organizer, calendar, alarm clock, portable media player etc are all incorporated in to a single device now popularly known as the “smart phone”.

- The smart phones can even be synced with one’s computer system.

- Eventually the smart phones achieved the capabilities like greater and better connectivity, web browsing, using third party applications and so on.

- Other advanced features include:
1. Pocket video Camera
2. Portable media players
3. Compact digital cameras
4. GPS navigation units

- The recent smart phones have web browsers pre- installed in them so as to facilitate the web browsing and accessing other web applications.

- The super a moled screens are now used instead of the earlier LCD displays.

- These smart phones very well support the standard web pages in their original form rather than optimizing them to be viewed through a phone like old feature phones.

How is testing on smart phones done?

- Smart phones also undergo rigorous testing to ensure that they are up to the standards and specifications.

- One way is to check the smart phone against a list of key features that must be in a cell phone for it to be a smart phone:

1. The Operating System

- A smart phone is always operated via an operating system rather than a proprietary firm ware as in the case of ordinary feature phones.

- Many of the smart phones make use of the following operating systems like iOS from Apple, Android from Google, Microsoft windows phones, Symbian from nokia, RIMS’s blackberry OS, Embedded Linux like MeeGo and Maemo etc.

- The above mentioned operating systems can be installed on different models.

- One is able to run third party applications on a smart phone only because the operating system of the smart phone is capable of integrating with the hardware of the phone.

- Likewise it also gains a third party support for the better functioning of its features.

2. Applications
- Even the ordinary feature phones include some sort of applications like address book, contact manager etc, but a smart phone serves even more.

- It includes applications for viewing and editing the Microsoft documents, download third party applications that serve other purposes.

3. Web access
- They have the capability of accessing the internet at high speeds via the advanced technologies of 3G and 4G and of course Wi- Fi!

4. Qwerty keypad
- Smart phone does includes qwerty key pad unlike the keypad of ordinary feature phones which have alphabetical order on top of a numeric keypad.

- It can be made available either through hardware or via the touch screens.

- Smart phones come in a whole lot of variety, in this case the performance and features of the models widely differ.

A smart phone is tested by testing its:

1. Usability: It involves the evaluation of the:
a) Menu navigation
b) Durability
c) Ease of use
d) Key pad layout
e) Software design
f) Screen resolution
g) Ergonomics

2. Call Quality: This involves the evaluation of the:
a) Ease of making and receiving calls
b) Managing contacts
c) Sound quality
d) Clarity of the reception
e) Messaging

3. Battery life: This involves the evaluation of the:
a) Talk time
b) Mp3 playback time

What are different features of smart phones?

Smart phones are now becoming a much in demand essential commodity for this third generation world. The demand for the smart phones has been increasing rapidly since the advent of much advanced and sophisticated technology.

One should be well versed with the current technologies in this tech savvy world and so we have this dedicated entirely to the discussion regarding smart phones.

Features of Smart Phones

- A smart phone is also like a mobile phone, but then what makes it different? Of course it’s so called smart features!

- A smart phone like any other phone is built up on a mobile computing platform but having more capabilities, abilities and connectivity when compared with their ordinary mobile counterparts.

- Today’s smart phones much like the earlier smart phones are incorporated with all the functions of a PDA (personal digital assistant), a camera as well as mobile phones or feature phones.

- But today’s technology has advanced so much so as to build smart phones that have functions of portable media players, pocket video cameras, compact digital cameras, GPS navigation units and so on incorporated in to them.

- The modern i.e., to say the recent smart phones come with more typical features like web browsers and super amoled touch screens which make the accessing of the web much easier than the ordinary feature phones on which only those web sites or pages can be viewed that have been optimized for the mobile phones.

- These smart phones are very much capable of displaying and accessing the standard web pages developed even with a very high resolution.

- Mobile broadband and wi- fi have also been incorporated in to these smart devices to provide them the ability of accessing data at high speeds.

- Many of the smart phones make use of the following operating systems:
1. iOS from Apple
2. Android from Google
3. Microsoft windows phones
4. Symbian from nokia
5. RIMS’s blackberry OS
6. Embedded Linux like MeeGo and Maemo etc

- The smart phones are designed in such a way that any OS can be installed on different models as well as one device is capable of receiving updates of more than one OS software all during its life time.

Difference between Feature phones and Smart phones

- Till now no official definition has been given regarding the difference between the feature phones and the smart phones.

- But, one point of significance is that the advance APIs or application programming interfaces for smart phones can run the third party applications with better integration with the operating system of the phone and its hardware.

- This much integration is not seen in ordinary feature phones.

- The feature phones in contrast to the smart phones make use of the proprietary firmware.

- A third party support is provided to these phones through platforms like BREW or Java ME and so on.

Features of first Smart Phone

- The first smart phone that was introduced was the IBM simon which was introduced in the year 1992. It had the following features:

1. Address book
2. Calendar
3. World clock
4. Note pad
5. Calculator
6. E- mail client
7. Fax and email features
8. Games

- It made use of a touch screen and stylus like modern smart phones.

- It lacked the ability to download third party applications as well as camera.

- However, that phone was highly sophisticated when compared to the other devices of that time.

Features of Nokia Communicator

- After that the nokia introduced its first smart phone range called “Nokia Communicator” releasing Nokia 9000 first in the range.

- The phone in this series had a clam shell like design with a QWERTY keyboard and a display with high resolution of 640 x 200 mega pixels.

- The screen sizes for the smart phones lie between 2 to 4 inches when measured diagonally.

- Some even come with a screen size of 5 inches but, this some what reduces the usability of the phone.

Network Interface Cards (NIC)

A Network Interface Card (NIC) provides the hardware interface between a computer and a network. A NIC technically is network adapter hardware in the form factor of an add-in card. Networked computers communicate with each other using a given protocol or agreed-upon language for transmitting data packets between the different machines, known as nodes. The network interface card acts as the liaison for the machine to both send and receive data on the LAN.
Some NIC cards work with wired connections while others are wireless. Most NICs support either wired Ethernet or WiFi wireless standards. In new computers, many NICs are now pre-installed by the manufacturer. NICs can be differentiated by their type of connectivity to the computer itself.

- 10/100 Ethernet : These cards are networking cards that are used most frequently in the home or small office setting. They are capable of speeds up to 10 or 100 megabits per second.
- Gigabit Ethernet :These NICs provide network transfer speeds of up to one Gigabit per second.
- Fiber Optics : These NICs use fiber optic cabling to reach speeds of 10 gigabits per second currently, with a specification under review to push this limit to 100 gigabits per second.
- Wireless NICs : These NICs provide the same networking capabilities as their wired counterparts, however, they have their own transfer capabilities. Speeds of 54 Mb/s are the most commonly available to wireless NICs without teaming several NICs together to combine bandwidths.
- Wireless Dongles : There is a wireless networking device used by individual machines that have access to a main computer that is connected to a wireless router. This wireless router allows the user to install wireless dongles instead of entire routers with each additional machine on the network.