The Web

The Web is a new entry into the distributed application arena. See Figure  9 on page  .

  

Figure 9: HTTP based Web

The big picture of the Web is similar to email. The system consists of Web servers and Web clients. The server is responsible for materializing pages of html encoded data. The client is responsible for displaying this information. The protocol spoken is called HTTP. The data is handled in a similar fashion as in MIME email.

There are two significant developments that empower the Web. One is the federated name space and the other is stateless computation. The federated name space defines a name for every object on the Web. The Web client can resolve the name and materialize the object. The space is federated allowing for anyone to splice into the name space at virtually any junction. The stateless computation gives incredible flexibility for machines entering and leaving the Web.

The Web is not perfect. As in email, the Web is unauthenticated, non-encrypted, does not have digital signatures, is easily spoofed, with no guarantee of service. The Web has become simultaneously the world's largest source of information and the world's largest source of miss information. There is indication of quality of content or availability of servers. In addition, the name space quickly degrades into stale and out-of-date entries.