Early web browsers – Transport Layer Security at a Glance

6.2 Early web browsers

At this point in time, two types of browsers were available to the early users of the WWW. The original browser developed by Berners-Lee had more sophisticated features but could only run on NeXT machines. The line-mode browser, on the other hand, could run on any platform but had fewer features and limited usability. After Berners-Lee’s call to action for developers to join, individuals across the world started writing browsers, in particular for the X Window System[44].

In 1993, the National Center for Supercomputing Applications (NCSA) at the University of Illinois released the first version of its web browser called Mosaic, which was developed by Marc Andreessen and his colleagues [40]. Mosaic ran on the X Window System and provided web users a user-friendly graphical interface with the same sort of point-and-click graphical manipulations they were used to on their personal computers (see Figure 6.2). Shortly afterward, NCSA released Mosaic versions for PC and Macintosh.

Figure 6.2: Mosaic web browser (source: Wikipedia)

In April 1994, Andreessen co-founded Netscape Communications Corporation. Their Netscape Navigator, a commercial product based on Mosaic, became the dominant web browser after it was released in December 1994 [40].

The availability of user-friendly web browsers on popular operating systems led to the rapid growth of the WWW. By the end of 1994, the web had 10,000 web servers, 2,000 of which were commercial, and a stunning 10 million users [44]. Individuals, institutions, and companies started extending web technology to realize new applications and address new needs. E-commerce and security turned out to be the most important features to be added soon.

6.3 From SSL to TLS

One of the first e-commerce applications was Book Stacks Unlimited, an online bookstore created by Charles M. Stack in 1992. The store began as a dial-up bulletin board, moved to the internet in 1994 in the books.com domain, and was eventually bought by Barnes & Noble [121].

In April 1995, John Wainwright, a computer scientist known for his pioneering work on object-oriented programming languages, ordered the first book ever sold by an online bookstore named after the South American river Amazon. It was Douglas Hofstadter’s Fluid Concepts And Creative Analogies: Computer Models Of The Fundamental Mechanisms Of Thought [70].

More e-commerce sites and services quickly followed. The prominent eBay marketplace opened its doors in 1995. In 1996, IndiaMART started offering its services over the web. Netflix launched its subscription video-on-demand service in 1997. The PayPal online payment system went online in 1998 [196]. With the growing number of e-commerce sites and services on the newly created web, the security of online shopping quickly became a serious concern.

To address these security needs, in 1994 Netscape Communications started designing a new protocol they named Secure Sockets Layer (SSL) for establishing a secure channel between a web server and a web browser. SSLv1, the first version of the SSL protocol, had essentially no means to ensure the integrity of messages being transmitted, though.