VINA BONNIE – MULTIPURPOSE VIRTUEMART 3 TEMPLATE

Vina Bonnie is a premium responsive multipurpose VirtueMart 3 Template which perfectly fits for any eCommerce website. Not only standing out in design, Vina Bonnie also impressed users by its features and functions. The most powerful and trendy features, including Mega Menu; Ajax Products Filter to filter product by Categories, Manufacturers, Price, Color, Size which don’t need reload the page; Category Treeview show all categories bring customers go everywhere in your store; Camera Image Slider with nice images and css3 effects bring great experience; Elevate Zoom: It’s particularly useful to display large version of product image, and this tool has been a famous solution in e-commerce websites; Product Carousel & Product Ticker extension shows kinds of products in responsive carousel such as featured products, new products, most viewed products, discount products; Customers also can communicate with you through Twitter and Blog;

 

Demo Vina Bonnie – Multipurpose VirtueMart 3 Template

Full Demo Page

Download Vina Bonnie – Multipurpose VirtueMart 3 Template

Download Direct Link

ENFOLD V3.7.1 – RESPONSIVE MULTI-PURPOSE THEME

Enfold v3.7.1 – Responsive Multi-Purpose Theme is a clean, super flexible and fully responsive WordPressTheme (try resizing your browser), suited for business websites, shop websites, and users who want to showcase their work on a neat portfolio site. The Theme is built on top of the fabulous Avia Framework and offers support for the WPML MULTI LANGUAGE plugin, just in case you need it

Enfold It comes with a plethora of options so you can modify layout, styling, colors and fonts directly from within the backend. Build your own clean skin or use one of 18 predefined skins right out from yourWordPress Admin Panel. Font, background and color options as well as the dynamic template builder will help you create the Website you need in no time. In addition to the global options you can set unique styling options for each entry as seen in the theme demo

Enfold SEO (Search engine optimization)

Enfold theme is built with SEO best practices in mind. It uses clean, semantical and valid HTML code and CSS so search engines can index the content of your site with ease. Important content is always placed before unimportent in your source code (eg: Blog Post content before Sidebar), Headlines are wrapped in heading tags (h1, h2, h3 etc) to signalise their importance to search engines.

Enfold also uses heavy internal site linking, which is also of vital for search engines (related posts, primary and secondary navigation menus, footer navigation, etc) With this WordPress Template you are well equipped to get a high google ranking and attract visitors to show them your fantastic work

Enfold v3.7.1 – Responsive Multi-Purpose Theme Changelog

2016 August 6th – v3.7.1
– style.css – new version number
– folder config-woocommerce:
– fixed: styling for the new tabbed front end account

Demo Enfold v3.7.1 – Responsive Multi-Purpose Theme

Full Demo Page

Download Enfold v3.7.1 – Responsive Multi-Purpose Theme

Download From UploadBoy

KEY TERMS in Computer Networks

Following are some important terms, which are frequently used in context of Computer Networks.

Terms Definition
1. ISO The OSI model is a product of the Open Systems Interconnection project at the International Organization for Standardization. ISO is a voluntary organization.
2. OSI Model Open System Interconnection is a model consisting of seven logical layers.
3. TCP/IP Model Transmission Control Protocol and Internet Protocol Model is based on four layer model which is based on Protocols.
4. UTP Unshielded Twisted Pair cable is a Wired/Guided media which consists of two conductors usually copper, each with its own colour plastic insulator
5. STP Shielded Twisted Pair cable is a Wired/Guided media has a metal foil or braided-mesh covering which encases each pair of insulated conductors. Shielding also eliminates crosstalk
6. PPP Point-to-Point connection is a protocol which is used as a communication link between two devices.
7. LAN Local Area Network is designed for small areas such as an office, group of building or a factory.
8. WAN Wide Area Network is used for the network that covers large distance such as cover states of a country
9. MAN Metropolitan Area Network uses the similar technology as LAN. It is designed to extend over the entire city.
10. Crosstalk Undesired effect of one circuit on another circuit. It can occur when one line picks up some signals travelling down another line. Example: telephone conversation when one can hear background conversations. It can be eliminated by shielding each pair of twisted pair cable.
11. PSTN Public Switched Telephone Network consists of telephone lines, cellular networks, satellites for communication, fiber optic cables etc. It is the combination of world’s (national, local and regional) circuit switched telephone network.
12. File Transfer, Access and Management (FTAM) Standard mechanism to access files and manages it. Users can access files in a remote computer and manage it.
13. Analog Transmission The signal is continuously variable in amplitude and frequency. Power requirement is high when compared with Digital Transmission.
14. Digital Transmission It is a sequence of voltage pulses. It is basically a series of discrete pulses. Security is better than Analog Transmission.

Comparison of OSI Reference Model and TCP/IP Reference Model

Following are some major differences between OSI Reference Model and TCP/IP Reference Model, with diagrammatic comparison below.

OSI(Open System Interconnection) TCP/IP(Transmission Control Protocol / Internet Protocol)
1. OSI is a generic, protocol independent standard, acting as a communication gateway between the network and end user. 1. TCP/IP model is based on standard protocols around which the Internet has developed. It is a communication protocol, which allows connection of hosts over a network.
2. In OSI model the transport layer guarantees the delivery of packets. 2. In TCP/IP model the transport layer does not guarantees delivery of packets. Still the TCP/IP model is more reliable.
3. Follows vertical approach. 3. Follows horizontal approach.
4. OSI model has a separate Presentation layer and Session layer. 4. TCP/IP does not have a separate Presentation layer or Session layer.
5. OSI is a reference model around which the networks are built. Generally it is used as a guidance tool. 5. TCP/IP model is, in a way implementation of the OSI model.
6. Network layer of OSI model provides both connection oriented and connectionless service. 6. The Network layer in TCP/IP model provides connectionless service.
7. OSI model has a problem of fitting the protocols into the model. 7. TCP/IP model does not fit any protocol
8. Protocols are hidden in OSI model and are easily replaced as the technology changes. 8. In TCP/IP replacing protocol is not easy.
9. OSI model defines services, interfaces and protocols very clearly and makes clear distinction between them. It is protocol independent. 9. In TCP/IP, services, interfaces and protocols are not clearly separated. It is also protocol dependent.
10. It has 7 layers 10. It has 4 layers

Diagrammatic Comparison between OSI Reference Model and TCP/IP Reference Model

between OSI (7 layers) and TCP/IP (4 layers) Model

The TCP/IP Reference Model

TCP/IP means Transmission Control Protocol and Internet Protocol. It is the network model used in the current Internet architecture as well. Protocols are set of rules which govern every possible communication over a network. These protocols describe the movement of data between the source and destination or the internet. These protocols offer simple naming and addressing schemes.

 

Diagram Representation of TCP/IP Model


Overview of TCP/IP reference model

TCP/IP that is Transmission Control Protocol and Internet Protocol was developed by Department of Defence’s Project Research Agency (ARPA, later DARPA) as a part of a research project of network interconnection to connect remote machines.

The features that stood out during the research, which led to making the TCP/IP reference model were:

  • Support for a flexible architecture. Adding more machines to a network was easy.
  • The network was robust, and connections remained intact untill the source and destination machines were functioning.

The overall idea was to allow one application on one computer to talk to(send data packets) another application running on different computer.


Description of different TCP/IP protocols

Layer 1: Host-to-network Layer

  1. Lowest layer of the all.
  2. Protocol is used to connect to the host, so that the packets can be sent over it.
  3. Varies from host to host and network to network.

 

Layer 2: Internet layer

  1. Selection of a packet switching network which is based on a connectionless internetwork layer is called a internet layer.
  2. It is the layer which holds the whole architecture together.
  3. It helps the packet to travel independently to the destination.
  4. Order in which packets are received is different from the way they are sent.
  5. IP (Internet Protocol) is used in this layer.

 

Layer 3: Transport Layer

  1. It decides if data transmission should be on parallel path or single path.
  2. Functions such as multiplexing, segmenting or splitting on the data is done by transport layer.
  3. The applications can read and write to the transport layer.
  4. Transport layer adds header information to the data.
  5. Transport layer breaks the message (data) into small units so that they are handled more efficiently by the network layer.
  6. Transport layer also arrange the packets to be sent, in sequence.

 

Layer 4: Application Layer

The TCP/IP specifications described a lot of applications that were at the top of the protocol stack. Some of them were TELNET, FTP, SMTP, DNS etc.

  1. TELNET is a two-way communication protocol which allows connecting to a remote machine and run applications on it.
  2. FTP(File Transfer Protocol) is a protocol, that allows File transfer amongst computer users connected over a network. It is reliable, simple and efficient.
  3. SMTP(Simple Mail Transport Protocol) is a protocol, which is used to transport electronic mail between a source and destination, directed via a route.
  4. DNS(Domain Name Server) resolves an IP address into a textual address for Hosts connected over a network.

Merits of TCP/IP model

  1. It operated independently.
  2. It is scalable.
  3. Client/server architecture.
  4. Supports a number of routing protocols.
  5. Can be used to establish a connection between two computers.

Demerits of TCP/IP

  1. In this, the transport layer does not guarantee delivery of packets.
  2. The model cannot be used in any other application.
  3. Replacing protocol is not easy.
  4. It has not clearly separated its services, interfaces and protocols.

Application Layer – OSI Model

It is the top most layer of OSI Model. Manipulation of data (information) in various ways is done in this layer which enables user or software to get access to the network. Some services provided by this layer includes: E-Mail, transferring of files, distributing the results to user, directory services, network resource etc.

 

Application Layer in ISO-OSI Model


FUNCTIONS OF APPLICATION LAYER:

  1. Mail Services : This layer provides the basis for E-mail forwarding and storage.
  2. Network Virtual Terminal : It allows a user to log on to a remote host. The application creates software emulation of a terminal at the remote host. User’s computer talks to the software terminal which in turn talks to the host and vice versa. Then the remote host believes it is communicating with one of its own terminals and allows user to log on.
  3. Directory Services : This layer provides access for global information about various services.
  4. File Transfer, Access and Management (FTAM) : It is a standard mechanism to access files and manages it. Users can access files in a remote computer and manage it. They can also retrieve files from a remote computer.

Presentation Layer – OSI Model

The primary goal of this layer is to take care of the syntax and semantics of the information exchanged between two communicating systems. Presentation layer takes care that the data is sent in such a way that the receiver will understand the information (data) and will be able to use the data. Languages (syntax) can be different of the two communicating systems. Under this condition presentation layer plays a role translator.

 

Presentation Layer in ISO-OSI Model


FUNCTIONS OF PRESENTATION LAYER:

  1. Translation : Before being transmitted, information in the form of characters and numbers should be changed to bit streams. The presentation layer is responsible for interoperability between encoding methods as different computers use different encoding methods. It translates data between the formats the network requires and the format the computer.
  2. Encryption : It carries out encryption at the transmitter and decryption at the receiver.
  3. Compression : It carries out data compression to reduce the bandwidth of the data to be transmitted. The primary role of Data compression is to reduce the number of bits to be 0transmitted. It is important in transmitting multimedia such as audio, video, text etc.

Session Layer – OSI Model

Its main aim is to establish, maintain and synchronize the interaction between communicating systems. Session layer manages and synchronize the conversation between two different applications. Transfer of data from one destination to another session layer streams of data are marked and are resynchronized properly, so that the ends of the messages are not cut prematurely and data loss is avoided.

 

Session Layer in ISO-OSI Model


FUNCTIONS OF SESSION LAYER:

  1. Dialog Control : This layer allows two systems to start communication with each other in half-duplex or full-duplex.
  2. Synchronization : This layer allows a process to add checkpoints which are considered as synchronization points into stream of data. Example: If a system is sending a file of 800 pages, adding checkpoints after every 50 pages is recommended. This ensures that 50 page unit is successfully received and acknowledged. This is beneficial at the time of crash as if a crash happens at page number 110; there is no need to retransmit 1 to100 pages.

Transport Layer – OSI Model

The main aim of transport layer is to be delivered the entire message from source to destination. Transport layer ensures whole message arrives intact and in order, ensuring both error control and flow control at the source to destination level. It decides if data transmission should be on parallel path or single path

Transport layer breaks the message (data) into small units so that they are handled more efficiently by the network layer and ensures that message arrives in order by checking error and flow control.

 

Transport Layer in ISO-OSI Model


FUNCTIONS OF TRANSPORT LAYER:

  1. Service Point Addressing : Transport Layer header includes service point address which is port address. This layer gets the message to the correct process on the computer unlike Network Layer, which gets each packet to the correct computer.
  2. Segmentation and Reassembling : A message is divided into segments; each segment contains sequence number, which enables this layer in reassembling the message. Message is reassembled correctly upon arrival at the destination and replaces packets which were lost in transmission.
  3. Connection Control : It includes 2 types :
    • Connectionless Transport Layer : Each segment is considered as an independent packet and delivered to the transport layer at the destination machine.
    • Connection Oriented Transport Layer : Before delivering packets, connection is made with transport layer at the destination machine.
  4. Flow Control : In this layer, flow control is performed end to end.
  5. Error Control : Error Control is performed end to end in this layer to ensure that the complete message arrives at the receiving transport layer without any error. Error Correction is done through retransmission.

Network Layer – OSI Model

The main aim of this layer is to deliver packets from source to destination across multiple links (networks). If two computers (system) are connected on the same link then there is no need for a network layer. It routes the signal through different channels to the other end and acts as a network controller.

It also divides the outgoing messages into packets and to assemble incoming packets into messages for higher levels.

 

Network Layer in ISO-OSI Model


FUNCTIONS OF NETWORK LAYER:

  1. It translates logical network address into physical address. Concerned with circuit, message or packet switching.
  2. Routers and gateways operate in the network layer. Mechanism is provided by Network Layer for routing the packets to final destination.
  3. Connection services are provided including network layer flow control, network layer error control and packet sequence control.
  4. Breaks larger packets into small packets.