Thursday, October 29, 2015

Variant object,HTTP , Origin Content Server,Accept headers

Variant objects in the context of HTTP are objects served by an Origin Content Server in a type of transmitted data variation (i.e. uncompressed, compressed, different languages, etc.).

HTTP/1.1 (1997?1999) introduces Content/Accept headers. These are used in HTTP requests and responses to state which variant the data is presented in.

Monday, October 26, 2015

Transport Layer Security,Secure Sockets Layer, by-product, message authentication,web browsing, electronic mail, Internet faxing, instant messaging, and voice-over-IP,transport layer

Transport Layer Security (TLS) and its predecessor, Secure Sockets Layer (SSL), are cryptographic protocols designed to provide communications security over a computer network.They use X.509 certificates and hence asymmetric cryptography to authenticate the counterparty with whom they are communicating,and to negotiate a symmetric key. This session key is then used to encrypt data flowing between the parties. This allows for data/message confidentiality, and message authentication codes for message integrity and as a by-product, message authentication. Several versions of the protocols are in widespread use in applications such as web browsing, electronic mail, Internet faxing, instant messaging, and voice-over-IP (VoIP). An important property in this context is forward secrecy, so the short-term session key cannot be derived from the long-term asymmetric secret key.

As a consequence of choosing X.509 certificates, certificate authorities and a public key infrastructure are necessary to verify the relation between a certificate and its owner, as well as to generate, sign, and administer the validity of certificates. While this can be more beneficial than verifying the identities via a web of trust, the 2013 mass surveillance disclosures made it more widely known that certificate authorities are a weak point from a security standpoint, allowing man-in-the-middle attacks (MITM).

In the Internet Protocol Suite, TLS and SSL encrypt the data of network connections in the application layer. In OSI model equivalences, TLS/SSL is initialized at layer 5 (session layer) and works at layer 6 (the presentation layer).The session layer has a handshake using an asymmetric cipher in order to establish cipher settings and a shared key for that session; then the presentation layer encrypts the rest of the communication using a symmetric cipher and that session key. In both models, TLS and SSL work on behalf of the underlying transport layer, whose segments carry encrypted data.

Friday, October 23, 2015

Usage in social media,iPhone ,Widget, web experiences

End users primarily use widgets to enhance their personal web experiences, or the web experiences of visitors to their personal sites.

The use of widgets has proven increasingly popular, where users of social media are able to add stand-alone applications to blogs, profiles and community pages. Widgets add utility in the same way that an iPhone application does. The developers of these widgets are often offering them as a form of sponsored content, which can pay for the cost of the development when the widgets' utility maps to the user's needs in a way where both parties gain. For example, a sports news brand might gain awareness and increased audience share in exchange for the utility of current game scores being instantly and dynamically available - the blog which posted the Sports score widget might gain in having a stickier site.

Element of control

One important factor with Widgets is that the host does not control the content. The content or the functionality it provides cannot be modified by the host. The content is pre-published by the publisher/author/service provider and the host can either accept that content or not use the widget. The host does, however, control the placement of the Widget. Because the host can always take the Widget down, it assures a large degree of mutual advantage and satisfaction with performance and content.

Monday, October 19, 2015

TLS handshake,control,client and server

When the connection starts, the record encapsulates a "control" protocol the handshake messaging protocol  (content type 22). This protocol is used to exchange all the information required by both sides for the exchange of the actual application data by TLS. It defines the messages formatting or containing this information and the order of their exchange. These may vary according to the demands of the client and server i.e., there are several possible procedures to set up the connection. This initial exchange results in a successful TLS connection (both parties ready to transfer application data with TLS) or an alert message

Friday, October 16, 2015

Suffix proxy,web content ,bypassing,web filters

A suffix proxy allows a user to access web content by appending the name of the proxy server to the URL of the requested content (e.g. ""). Suffix proxy servers are easier to use than regular proxy servers but they do not offer high levels of anonymity and their primary use is for bypassing web filters. However, this is rarely used due to more advanced web filters.

Tuesday, October 13, 2015

Shared web hosting service_Name-based,virtual hosting,shared IP hosting,multiple host,single machine

In name-based virtual hosting, also called shared IP hosting, the virtual hosts serve multiple host names on a single machine with a single IP address. This is possible because when a web browser requests a resource from a web server using HTTP/1.1 it includes the requested host name as part of the request. The server uses this information to determine which web site to show the user.

Friday, October 9, 2015

Shared web hosting service,Shared web hosting service,sits,Internet

A shared web hosting service refers to a web hosting service where many websites reside on one web server connected to the Internet. Each site "sits" on its own partition, or section/place on the server, to keep it separate from other sites. This is generally the most economical option for hosting, as many people share the overall cost of server maintenance.

Tuesday, October 6, 2015

Router,networking device,web pages, email, IM,DSL router,ISP networks, Internet backbone

A router is a networking device that forwards data packets between computer networks. A router is connected to two or more data lines from different networks (as opposed to a network switch, which connects data lines from one single network). When a data packet comes in on one of the lines, the router reads the address information in the packet to determine its ultimate destination. Then, using information in its routing table or routing policy, it directs the packet to the next network on its journey. This creates an overlay internetwork. Routers perform the "traffic directing" functions on the Internet. A data packet is typically forwarded from one router to another through the networks that constitute the internetwork until it reaches its destination node. q

The most familiar type of routers are home and small office routers that simply pass data, such as web pages, email, IM, and videos between the home computers and the Internet. An example of a router would be the owner's cable or DSL router, which connects to the Internet through an ISP. More sophisticated routers, such as enterprise routers, connect large business or ISP networks up to the powerful core routers that forward data at high speed along the optical fiber lines of the Internet backbone. Though routers are typically dedicated hardware devices, use of software-based routers has grown increasingly common.

Saturday, October 3, 2015

Quick Start Joomla Package,Joomla,CMS, modules,

Quick Start Package is fully functional Joomla package which contains CMS, modules, selected templates and plugins with the configurations and the data that is used in the demo website. The sample data can also be personalized based on the template in quick start package and is different from the default Joomla! 3.x (2.5.x) package.