What is Squid proxy server and how to install it?

Squid is the web proxy server which provide proxy and cache service for hyper text transfer protocol,File transfer protocol and many network protocol.squid can implement for cache and proxy socket layer and also implement Domain name server lookup.Squid is used for proxy which support many protol such as Internet cache protocol,Hyper text cache protocol,Cache array routing protocol and web cache coordination protocol.
Squid Proxy

The squid proxy server provide excellent solution to proxy and caching server needs,it has access control mechanism,monitoring critical parameter and all.when you use squid proxy server keep in mind squid server has configured and should be large amount of physical memory in cache memory to increase the performance.
squid1

Now we learn how to install the squid proxy server on ubuntu.

There is some steps to install squid proxy server which is as follows:

Step 1: First of all login into the terminal with username and password.

Step 2: Now enter the following command to install the squid server.

sudo apt-get install squid3

Step 3: Now we have to edit the configuration file of squid which is /etc/squid3/squid.conf. we will edit the “squid.conf” and will modify it to change the behaviour of squid server.
First copy the original configuration file to re use in future.

sudo cp /etc/squid3/squid.conf /etc/squid3/squid.conf.original
sudo chmod a-w /etc/squid3/squid.conf.original

Step 4: If you want to change the default port then change the http_port

http_port 8888

Step 5: Change the visible hastname to give the squid server specific hostname.
visible_hostname jay

Step 6: you can use access control to to be only available to users.
So please add the following line into the /etc/squid3/squid.conf file:

acl fortytwo_network src 192.168.x.x/24

And add the following to top of the http_access section of conf file.
http_access allow fortytwo_network

Step 7: you can set the internet erviec available only during business hours.
Add the following line to conf file
http_access allow biz_network biz_hours

Step 8: After making changes save the file and restart the service.
sudo service squid3 restart

Using HTML and CSS How to make a responsive website in easy steps.

Using HTML and CSS How to make a responsive website in easy steps.
STEP 1 : Add the proper DOCTYPE and viewport META TAG to the top of your page
When we start a mobile friendly page begin with the following- adding the HTML5 DOCTYPE to the very top of our page and viewport META tag to the HEAD portion: For example
<!DOCTYPE html>
<html>
<title>This is a test page</title>
<meta name=”viewport” content=”width=device-width, initial-scale=1″>
The view meta tag once added does something tangible – it triggers the mobile browser to start showing our page in its actual dimention relative to the dimension of the mobile browser, so a 800px wide page on a 320px wide mobile device will now show, well, only 320 pixels of the page at a time. Prior to adding the viewport meta tag, the mobile browser will automatically put page into a ” virtual window ” that’s zoomed out to fit the entire 800px wide page on its tiny 320px screen, zooming out everything to make that possible.
when user building a responsive website, or making responsive an existing site, the first element to look at is the layout. When we build responsive websites, we always started by creating a non-responsive layout, fixed at the size.For example default width size 1100px.
<meta name=”viewport” content=”width=device-width,initial-scale=1,maximum-scale=1,user-scale=no”>
<mata http-equiv=”X-UA-compatible” content=”IE=edge,chrome=1″>
<meta nam”HandheldFriendly” content=”true”>
It’s now time to add some media queries. According to the W3C site, a media query consist of a media type and zero or more expressions that check for the conditions of perticular media features. By using media queries, presentations can be tailored to a specific range allows your website to look good on all kinds of displays, from smartphones to big screens.
Media queries depends of your website layout, so it’s kind a difficult for me to provide you a ready to use snippet. However, the code below is a good starting point for most website. In this example, #primary is the main content area, and #secondary the sidebar.
By Having a look at the code, you can see that I defined two sizes:
The first have a maximum width of 1060px and is optimized for tablet landscape display. #primary occupies 67% of its parent container, and #secondary 30%, plus a 3% left margin.
The second size is designed for tablet portrait and smaller sizes. Due to the small sizes of smartphones screens, I decided to give #primary a 100% width. #secondary also have a 100% width, and will be displayed below #primary.
As i already said, we will probably have to adapt this code a bit to fit the specific needs of our website. Paste it on your site .css file.
/* Tablet Landscape */
@media screen and(max-width:1060px){
#primary {width:67%; }
#secondary { width:3%; margin-left:3% ;}
}
/* Tabled Portratit */
@media screen and(max-width:768px){
#primary {width:100%; }
#secondary {width:100%; margin:0; bordered:none;}
}
Once done, let’s see how responsive your layout is.
2 – Medias
A responsive layout is the first step to a fully responsive website. Now, let’s focus on avery important aspect of a modern website: medias, such as videos or images.
The CSS code below will ensure that your images will never be bigger than their parent container. It’s super simple and it works for most websites. Please note that the max-width directine is not recognized by older browser such as IE6. In order to work, this code snipppet have to be inserted into your CSS stylesheet.
img{ max-width:100%;}
Although the technique above is efficient, sometimes we may need to have more control over images and display a different image according to the client display size.
Here is a technique example. Let’s start with the html:
<img src=”image.jpg”>
data-src-600px=”image-600px.jpg”
data-src-800px=”image-800px.jpg”
alt=””>
As user can see, we used the data -*attribute to store replacement images urls. Now, let’s use the full power of CSS3 to replace the default image by one of the specified replacement images if the min-device-width condition is matched:
@media(min-device-width:600px){
img[data-src-600px] {
content:attr(data-src-600px,url);
}
}
@ media(min-device-width:800px){
img[data-src-800px] {
content:attr(data-src-800px,url);
}
}
Now let’s have a look to another very important media in today’s website, videos. Mostly websites are using videos from third parties sites such as YouTube or Vimeo, I decided to focus on the elastic video technique. This technique allows you to make embedded videos responsive.
The html:
<div class=”video-container”>
<iframe src=”http://player.vimeo.com/video/6284199?title=0&btline=0&portraint=0″ width=”800″ height=”450″ frameborder=”0″></frame>
</div>
And now, the CSS:
.video-container{
position: relative;
padding-bottom:56.25%;
padding-top:30px;
height:0;
overflow:hidden;
}
.video-container iframe,
.video-container object,
.video-container embed {
position: absolute;
top:0;
left:0;
width:100%;
height:100%
}

stack

once we applied this code to our website, embedded videos are now responsive.
3- Typography
This is the last step is definitely important, but it is neglected by developers when it comes to responsive websites : Typography.
Until now, mostly users and developers (including myself!) used pixels to define font sizes. While pixels are ok when our website has a fixed width, a responsive website should have a responsive font. Indeed, a responsive font size should be related to its parent container width, so it can adapt to the screen of the client.
The CSS3 specification included a new unit named rems. They work almost identically to the em unit, but are relative to the html element, which make them a lot easier to use than ems. As rems are relative to the html element,don’t forget to reset html font size:
html {font-size:100%;}
Once done, you can define responsive font sizes as shown below:
@media(min-width:640px){body {font-size:1rem;}}
@media(min-width:960px){body{font-size:1.2rem;}}
@media(min-width:1100px){body{font-size:1.5rem;}}
There are few important points are used to mobile friendly and responsive website.

Internet is often portrayed as a single global system

FVO9j

Although the internet is often portrayed as a single global system, in practice it’s not really anything of the sort. Because it’s relatively easy to identify someone’s approximate location by means of their IP address, and because it’s very easy for a web site operator to find the IP address of a visitor, many sites deliberately block users from specific countries.This is generally done for marketing or legal reasons. For example, look at the BBC News pages from a puter in the US and you’ll see news that’s mostly aimed at a British audience. Look at the same page from the USA and you’ll see a different selection of stories.In many cases you can choose which version of a site you want to see. But in some cases you’re prohibited from doing so.For example, a video clip that’s only licences for display in Europe won’t be viewable by someone in the USA.Needless to say, it’s possible to work around these inconveniences. You simply need to subscribe to a proxy service. You then log into the proxy server, type in the details of the site you want to visit, and the proxy server requests the information on your behalf. Because the proxy is based in the country whose information you want to view, there’s no problem.Hide My Ass proxy service windowOne major proxy service pany, HMA, lets you choose from proxy servers in some 75 countries. If you don’t want to pay the monthly fee, however, you can still access proxies in the UK, USA and the Netherlands, which gives you a pretty good chance of accessing the information you need. Just enter the country you want to appear to be ing from, and the URL of the site you want to visit, and the system does the rest.So next time you get an error message saying that the content you want to see isn’t available in your region, try surfing to hidemyass or whatismyip and take it from there. Just make sure you select UK, USA or Netherlands from the list, in order to access the free service.Also with proxy server we can save more time and packet data, because usually a proxy server have cache feature that will cache every requests. XYZ open a webpage facebook., and then after 5 minutes Valentino also open facebook. When XYZ open facebook. maybe the webpage will open on 15 second because it was the first load and then the proxy server cached the data, when Valentino open facebook. maybe it will open in 5 second, more faster than XYZ, because the facebook. data already stored on proxy server and Valentino will load the static page of facebook. from proxy and load the dynamic data from facebook web pages.

Sharing proxy cost with other people making it more affordable compared to private proxies cost

images

 

Shared proxies are used not only by you but also with other 4 to 5 person anonymous people. This means you will be sharing the cost with other people making it more affordable compared to private proxies. Although there are some free proxies that don’t cost a thing, they are known to be less effective thus, people opt for shared proxies instead.just like the private proxies, the shared ones are equally efficient and effective as well. It works just the same and offers a good layer of protection as well. Shared proxies are also known to be the perfect solution for the beginners. Since you don’t have to pay much, you can easily experiment on various shared proxies.because private proxies are used only by the person who bought it (in this case, you), this means you don’t have to deal with any risks entailed with sharing. You never know what other people are up to thus, protecting your pertinent information is a must. This can be obtained by a private proxy.No ads and slow internet connection if you’ve had enough with those annoying ads that would pop up from different sites then it’s advisable to buy scrapebox proxies that are private. Such type of proxy spares you from viewing those annoying ads.You also don’t have to deal with slow internet connection brought by sharing proxies. Although this does not happen all the time, many individuals claim that slow internet connection is always involved at certain periods with the shared type.If you wish to share your proxies with multiple users then you can have shared proxies. Compare to private proxies, this type enables other users to use the services. The price is also more affordable if ever you decide to choose shared proxies.When you access a website on the Internet, some of your personal information and details are made public.For business owners, this is something that they do not want to risk especially since these pieces of information can be used without their consent.This is primarily one of the reasons why they prefer to shed out some money just to enjoy shared or private proxies.A part from business owners, individuals who want to have private browsing experience are also willing to incur costs just to enjoy exclusivity.You’ve definitely heard your friends, or other computer users talking about proxies, particularly shared proxies. Though you’ve seen the proxy option from your internet setting, but you really don’t have any idea about what it is. Therefore, this also means that you’re not well-verse about shared proxies. The term ‘shared’ defines that shared proxies are being utilized by several users or multiple users. This simply means that once a user purchases a shared proxy, it can definitely be accessed by other people. If you think this option is okay with you, then you can pursue a shared proxy server. Since you are a certified online savvy, you are aware that whenever you visit certain websites, your PC or laptop acquires cookies, from each and every site that you access.

Private proxy keeps your identity and internet privacy safe from others

download (1)

If you are looking to buy a proxy, you must know there is more than one type of proxies. The main two proxies are private proxy and shared proxy. Private proxy is also known as the dedicated proxy. It provides you your own private proxy server and no one can access it, except you. Besides the benefit of not sharing in the consequences of other actions, there are various other advantages of using a private proxy.Private proxy keeps your information safe from hackers, since hackers can install a key logger to record every information from your computer, your private proxy will prevent them to do so. A private proxy keeps your identity and internet privacy safe from others so that your information is not accessed by hackers as they use your information for illegal purpose.It is fast, it can really speed up whatever work you are doing.It is safe; it helps to bypass filter and firewalls.It offers wide selection of geographic locations for their I.P addresses.You always give a lot of information about yourself on the internet. Thus, by using a private proxy, you can be sure that your browsing sessions are safe and secure because even your computer can become a spy watching you and your every move. The most common type of hacking is gathering the information about where you live, your phone number, what business you’re in. It might not seem very sensitive initially, but can create very big hassle in the long run because hackers can send the information to hundreds of company and use your information to accomplish their illegal motives.There are many advantages of using private proxies and that what you pay for. Some people think it is costly, but the benefits that you get are worth every penny spent on them. The major benefits include more of IP addresses, faster speed, and wider selection of geographic location. It is worth paying for all the benefits you get with your own dedicated proxy. A private proxy is the best way to keep all the browsing history safe.In fact, in the event you do your study carefully enough, you can frequently times find these severs accessible at no cost or very minimum costs. A free anonymous proxy server is becoming very well-known among web marketers and users today, and you very well could benefit from one of those machines also.To find a great proxy server list, simply type it into Google, and many results will come up. Whether or not you would like a proxy server for usenet or any other pc machine, hopefully this info will enlighten you in regards to what a proxy server is, and most significantly, how it could benefit you down the road with out breaking the bank for one.A proxy server is regarded as a standalone device or software program running on a host that acts as a packet filter for connection requests. It’s an intermediary device sitting in between hosts and server that filters the requests by checking IP Addresses, Protocol and/or application content. When the proxy server deems the connection request to become valid, then it connects towards the application server and requests the service on behalf from the client device.

Information about SOCKS Proxy

SOCKS help to work on application like circuit level proxy due to his intend protocol. SOCKS proxy known as application proxies which was mostly different from normal proxy like HTTP proxy . SOCKS is short of Socket secure which work on protocol and with help of proxy server make routes network packets between clients and server . SOCKS proxy is also useful to get bypass all restriction websites which was blocked by Government ,school and at workplace. SOCKS proxy is mostly use in Workstation were SOCKS install by clients either in application or in deep of  TCP/IP stack which help to redirect packets with the help of client software. Also SOCKS proxy servers might produce reverse connections. In some cases your native administrator might block all outgoing connections for security reasons. At identical time incoming connections can be unbroken open. in this case rather than establishing affiliation from your computer to SOCKS proxy server, you’ll raise SOCKS proxy server to ascertain reference to your computer. After that, communication between consumer and SOCKS proxy server can stay identical as if use establishes affiliation by his/her own.With SOCKS you can achieve good  security, responsiveness and responsibility and enhances network management and tractability .SOCKS proxy will settle for a client’s request outside the firewall, read its access and transmit the request to an external server.SOCKS proxies having two different types SOCKS 4 and SOCKS 5 they have there own benefit. Uses of SOCKS 4 and SOCKS 5 depend upon their network application which was have with the users. SOCKS 4 is capable to handle protocols which was based on TCP like TELNET, FTP, HTTP, GOPHER, etc. The external hosts which was get resolve by SOCKS 4 lookups DNS . SOCKS 4 is also capable to control among strict authentication schemes, similarly as supports network registration IPv6. SOCKS 5 is latest version capable to handle both protocol such as TCP and UDP. SOCKS 5 secure supports user authentication more than SOCKS 4. SOCKS 5 is best one for gaining acceptance for web base client/server solutions to providers which was approved by IETF standard . Emerging security models such as IPSec and PPTP/L2TP get wide range of ability of inter operate with SOCKS 5. You can easily handle the great demanding enterprise-level intranet and Internet applications with SOCKS 5 .This simple ability permits SOCKS-based solutions to be deployed forthwith, whereas taking advantage of the newest advances in authentication and cryptography technologies offered by these rising standards.Current leading Internet solutions vendors such as Attachmate Corporation, Aventail Corporation, Bay Networks, Inc., Hummingbird Communications, Ltd., IBM Corporation, Netscape Communications Corporation, Network Appliance, Inc., Oracle Corporation, and others are getting good supports due to SOCKS 5 base products.

stackproxy

What is Protocol?

In information technology, a protocol is the special set of rules that end points in a telecommunication connection use when they communicate. Protocols specify interactions between the communicating entities.

There are various types of protocol and each has different work which are as follows:

1. Bluetooth protocol:
The wireless data exchange standard Bluetooth uses a variety of protocols. Core protocols are defined by the trade organization Bluetooth SIG. Additional protocols have been adopted from other standards bodies. This article gives an overview of the core protocols and those adopted protocols that are widely used.

Blutooth protocol

2. Fibre Channel network protocols:
Communication between devices in a fibre channel network uses different elements of the Fibre Channel standards. The following sections introduce the main concepts and show how a combination of primitives and frames is required.

Fibre network Protocol

3. Internet Protocol Suite or TCP/IP model :
The Internet protocol suite is the computer networking model and set of communications protocols used on the Internet and similar computer networks. It is commonly known as TCP/IP, because its most important protocols, the Transmission Control Protocol (TCP) and the Internet Protocol (IP), were the first networking protocols defined in this standard.

TCPIP_Protocol_Suite

4. OSI protocols:
OSI protocols stacks are split into seven layers. The layers form a hierarchy of functionality starting with the physical hardware components to the user interfaces at the software application level. Each layer receives information from the layer above, processes it and passes it down to the next layer. Each layer adds its own encapsulation information (header) to the incoming information before it is passed to the lower layer. Headers generally include address of destination and source, check sums (for error control), type of protocol used in the current layer, and other options such as flow control options and sequence numbers (used to ensure data is sent in order).

osi

5. SSH Secure Shell:
This allows a user to run commands on a machine’s command prompt without them being physically present near the machine. It also allows a user to establish a secure channel over an insecure network in a client-server architecture, connecting an SSH client application with an SSH server.

ssh

6. FTP File Transfer Protocol:
The File Transfer Protocol (FTP) is a standard network protocol used to transfer computer files from one host to another host over a TCP-based network, such as the Internet.FTP is built on a client-server architecture and uses separate control and data connections between the client and the server.

ftp

7. SMTP Simple Mail Transfer Protocol:
Simple Mail Transfer Protocol (SMTP) is an Internet standard for electronic mail (e-mail) transmission.SMTP by default uses TCP port 25. The protocol for mail submission is the same, but uses port 587. SMTP connections secured by SSL, known as SMTPS, default to port 465.

smtp-simple-mail-transfer3

8. Telnet Telephone Network:
Telnet is an application protocol used on the Internet or local area networks to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. User data is interspersed in-band with Telnet control information in an 8-bit byte oriented data connection over the Transmission Control Protocol (TCP).

telnet

9. HTTP Hyper Text Transfer Protocol:
The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, hypermedia information systems.HTTP is the foundation of data communication for the World Wide Web.Hypertext is structured text that uses logical links (hyperlinks) between nodes containing text. HTTP is the protocol to exchange or transfer hypertext.

HTTP

10. SSL Secure Socket 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.

ssl-handshake