Free What is a Web-Service Essay Sample
A web service is a mode of communication involving two electronic gadgets through a network. It is also called application service. It is a software application, based on the website that exchange information with other website applications. It involves a standardized way of incorporating applications such as Simple Object Access Protocol (SOAP), Extensible Markup Language (XML), Universal Description, Discovery and Integration (UDDI) and Web Service Definition Language (WSDL) (Gregory, 2010).
In web-service, SOAP is used in the transferring of information while XML is used in the tagging of data. USSDI is instrumental when outlining the available services. Additionally, WSDL helps in the description of the available services. Web services are useful in business organizations for both internal and external communications. It makes it possible for them to exchange information among themselves, and to the clients. In the process, there is no display of any intimate knowledge of information technology systems.
Moreover, web services depend on other protocols such as File Transfer protocol (FTP), Simple Mail Transfer Protocol (SMTP) and Hyper Text Transfer protocol (HTTP) in the transfer of information behind the firewall. It can also use the Extensible Messaging and Presence Protocol (EMPP). Web service enables various applications from distinct sources to exchange of data among themselves, with fast custom coding. The availability of communication in XML enables the web services to operate without any restriction to a certain system or language (Hatch, 2010). Some of the communications involved are Java and Perl.
Additionally, web service offers users the Graphical User Interface (GUI), which other services provide. However, they do not need a browser or a Hyper Text Mark-up Language (HTML). Moreover, web services have firewalls that offer security measures. Web services are divided into two categories; REST-compliant Web services and the arbitrary Web services.
Describe, with examples, a Mashup (web service variety).
A mashup is an application or page web that employs and integrates information, presentations or practicality from at least two origins in the construction of new services. It involves simple, swift incorporation, often applying clear Application Programming Interfaces (APIs) in the production of quality results, which were not essentially the initial aim of producing the raw source information (Hatch, 2010). Integration, visualization, and collection are the key features of a mashup. They are used online, or they become client services so as to ensure that there is a lasting access to information of other applications.
Moreover, mashups are instrumental in the development of Web 2.0., and social software. Its machines are easy to use by the clients since they do not need programming competence, but aid physical combination of services, constituents and widgets. One of the examples of mashups is the Microsoft Windows operating system. Another one involves the use of Google maps practically and information in map navigation.
Critically compare SOAP and REST
There are certain distinctions between REST and SOAP. REST means Representation State Transfer while SOAP stands for Simple Object Access Protocol. REST is an architecture that applies HTTP system and methods. SOAP, on the other hand, is a protocol that transfers data to different locations. It also has excellent standards in terms of interoperability. For example, it involves HTTP, JMS and SMTP (Gregory, 2010). Moreover, SOAP is based on message concept while REST is not based on message concept.
In addition, REST is simple given that it eases the publishing of the clients' business information. This is because it uses the XML and HTTP since the two reduces the use of WSDL and UDDI services. Conversely, SOAP is more complex than the REST. This is because it is resilient. It features include security identification, business conduct, precedence, routing data and expiration.
REST's architecture involves the clients and servers. The clients introduce requests to the servers who, in turn, address the requests and provide a suitable feedback. On the contrary, SOAP's architecture comprises of multiple specification layers. These include message formatting, processing and transporting.
Describe the vulnerability, which might exist in a web service that each of the attack methods could exploit.
XML poisoning can serve as a vulnerability of the targeted web service. The XML external entity can also be changed by an attacker, hence alteration or loss of vital information. XPath Injection involves an attack method of exploiting websites (Gomaa, 2002). A certain attacker might remove an XML file by use of the XPath thereby allowing the attacker the chance to alter change information by manipulating the user's database. Consequently, vital documents and information are compromised. On the other hand, WSDI attack has a vulnerability that involves someone accessing the restricted methods. Therefore, it is essential to protect files and restrict their access.
Furthermore, Recursive payload attack develops nesting of information elements, hence choking the XML parsers. This, in turn, leads to denial of services. On the other hand, parameter tempering is used by Internet thieves by changing information in the Uniform Resource Location without any permission (URL). In addition, RSS is instrumental in exchange of information on portals and web services. However, attackers can visit the website and executes the information by using the RSS feeds. They can also mutate the clients' information (Auger, 2006). Also, oversized payloads protect the attacks on large files that have 100 megabytes. File sizes can be reduced by the attackers hence loss of information. The large could be an indication that the attackers are intending to change the parser so as to create service denial.