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EMBEDDED WEB TECHNOLOGY
A SEMINAR ON
EMBEDDED WEB TECHNOLOGYBY
SRUTHI R BABUS7ECE
13134240COLLEGE OF ENGINEERING PATHANAPURAM
1COLLEGE OF ENGINEERIGNG PATHANAPURAM
EMBEDDED WEB TECHNOLOGY
COLLEGE OF ENGINEERING PATHANAPURAMCUSAT UNIVERSITY
BONAFIDE CERTIFICATE
Done by
Sruthi r babu
This is to certify that the seminar work entitled “EMBEDDED WEB TECHNOLOGY” is a bonafide record of the seminar done by SRUTHI R BABU
in partial fulfillment of the requirements for the award of B.Tech Degree Electronics and Communication by Cochin University of Science and Technology
Seminar Coordinators
Mrs.Sreedevi M.G Mr.Amsu Thejus M Mr.Shafi
Asst.prof. Asst.prof. Asst.prof
Dept.of ECE Dept. of ECE Dept.of ECE
Head of the Department
Mrs.Navitha K. Krishnan
Dept.of ECE
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ACKNOWLEDGEMENTBehind every achievement lies an unfathomable sea of gratitude to those who actuated it,
without them it would never have into existence .To them we lay the word of gratitude imprinted
within us.
I would like to express my sincere thanks to our respected Principal
Dr.ANATHARASHMI, M.TECH, PhDfor all the blessing and help provided during the period
of seminar work.
I wish to express my sincere thanks to Mrs. NAVITHA.K. KRISHNAN Head of the
Department of electronics and communication Engineering, for the continuous help over the
period of seminar work.
I am indebted to my internal guide Mrs.SREEDEVI M.G, Assistant Professor,
Department of electronics and communication Engineering, for his constant help and creative
ideas over the period of seminar work.
I am indebted to my internal guide Mr.AMSU THEJUS M, Assistant Professor,
Department of electronics and communication Engineering, for his constant help and creative
ideas over the period of seminar work.
I am indebted to my internal guide Mr. SHAFI, Assistant Professor, Department of
electronics and communication Engineering, for his constant help and creative ideas over the
period of seminar work
I would like to extend my warmest thanks to all our Lab Technicians for
helping me in this venture. Unflinching support and encouragement from the members of my
family, friends and staff member in COLLEGE OF ENGINEERING PATHANAPURAM
helped me a long way to complete my seminar work. I must thank them all from my depths of
my heart.
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EMBEDDED WEB TECHNOLOGY
CONTENTS
1. ABSTRACT
2. INTRODUCTION
3. EWT-BASICS
3.1 EMBEDDED WEB TECHNOLOGY
3.2 EMBEDDED WEB SERVER
3.3 CLIENT –SERVER MODEL
3.4HTML AND XML
4. EWT EXPLAINATION
4.1 COMPARISON OF A TYPICAL WEB SERVER ENVIRONMENT VERSUS AN EMBEDDED, REAL-TIME ENVIRONMENT
4.2 OVERVIEW OF WORLD WIDE WEB
4.3 PUTTING WEB INTO EMBEDDED SYSTEM
4.4 TEMPEST FEATURES
5. EWT WORKING
6. ADVANTAGES OF EWT
7. APPLICATIONS
8. CONCLUSIONS
9. REFERENCES
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ABSTRACT
Embedded Web Technology (EWT) is regarded as the 'marriage' of Web technologies with
embedded systems. In other words, the software developed for embedded systems is applied by
making use of the Internet. Embedded technology has been around for a long time and its use has
gradually expanded into the PC market. Speed, accuracy, reliability were the reasons why
embedded technology entered computers. With a great market size of billions in the next coming
years, the future is embedded. Embedded systems contain processors, software, input sensors and
output actuators, which work as the controls of a device and are subject to constraints. These
Embedded systems may not have disk drives, keyboards, display devices and are typically
restricted in terms of power, memory, GUIs and debugging interfaces. The central building
blocks are microcontrollers, i.e. microprocessors integrated with memory units and specific
peripherals for the observation and control of these embedded systems. On the other hand, Web
technologies employ client server models
The embedded Web system works on the same principle as those traditional Web request-
response systems. Web pages from the embedded system (server) are transmitted to the Web
browser (client), which implements the user interface (Presentation layer). In other cases, the
embedded system dynamically generates the pages to convey the current state of the device to
the user at the centralized location. These end users can also use the Web browser to send the
information to the embedded system for the configuration and control of the device.
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CHAPTER 1
INTRODUCTIONNow we are living in a web- enabled world .Internet is now a vital part of our life .The changes
that internet has caused is that much that today rather than representing the earth as a
combination of continents and oceans, representing as a combination of inter linked Pcs, fax
machines and other such devices is more efficient. In this sense, it’s good to have some
information regarding Embedded Web Technology (EWT) embedded web technology was
developed by members of NASA Lewis research centre, flight software engineering branch of
the engineering and design analysis division of the engineering and technical services
directorate. It is an integration of embedded system and web technology. As this technology is an
integration of embedded system and web technology it is being used to turn units into internet
appliances
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CHAPTER 2
EWT-BASICS
. As this seminar is about embedded web technology its necessary that we should understand
about the following which are actually key for understanding embedded web technology
Embedded system
Embedded web server
Client server model
Embedded system
An embedded system is a computer system with a dedicated function within a larger
mechanical or electrical system, often with real-time computing constraints. It is embedded as
part of a complete device often including hardware and mechanical parts. Embedded
systems control many devices in common use today. Embedded technology is software or
hardware that is hidden—embedded—in a large device or system. It typically refers to a fixed
function device, as compared with a PC, which runs general-purpose applications Properties of
typical embedded computers when compared with general-purpose ones are. low power
consumption, small size, rugged operating ranges and low per-unit cost. This comes at the price
of limited processing resources, which make them significantly more difficult to program and to
interface with. However, by building intelligence mechanisms on the top of the hardware, taking
advantage of possible existing sensors and the existence of a network of embedded units, one can
both optimally manage available resources at the unit and network levels as well as provide
augmented functionalities, well beyond those available. For example, intelligent techniques can
be designed to manage power consumption of embedded systems. Since the embedded system is
dedicated to specific tasks, design engineers can optimize it to reduce the size and cost of the
product and increase the reliability and performance. Some embedded systems are mass-
produced, benefiting from economies of scale
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Embedded systems are commonly found in consumer, cooking, industrial, automotive,
medical, commercial and military applications. Telecommunications systems employ
numerous embedded systems from telephone switches for the network to cell phones at the
end-user. Computer networking uses dedicated routers and network bridges to route
dataConsumer electronics include personal digital assistants (PDAs), mp3 players, mobile
phones, videogame consoles,digital cameras, DVD players, GPS receivers, and printers.
Household appliances, such as microwave ovens, washing machines and dishwashers,
include embedded systems to provide flexibility, efficiency and features
Embedded Systems talk with the outside world via peripherals, such as:
Serial Communication Interfaces (SCI): RS-232, RS-422, RS-485 etc.
Synchronous Serial Communication Interface: I2C, SPI, SSC and ESSI (Enhanced
Synchronous Serial Interface)
Universal Serial Bus (USB)
Multi Media Cards (SD Cards, Compact Flash etc.)
Networks: Ethernet, Lon Works, etc
Field buses: CAN-Bus, LIN-Bus, PROFIBUS, etc.
Timers: PLL(s), Capture/Compare and Time Processing Units
Discrete IO: aka General Purpose Input/Output (GPIO)
Analog to Digital/Digital to Analog (ADC/DAC)
Debugging: JTAG, ISP, ICSP, BDM Port, BITP, and DP9 ports.
In addition to the core operating system, many embedded systems have additional upper-layer
software components. These components consist of networking protocol stacks
like CAN, TCP/IP, FTP, HTTP, and HTTPS, and also included storage capabilities like FAT and
flash memory management systems. If the embedded device has audio and video capabilities,
then the appropriate drivers and codecs will be present in the system
Embedded web server
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Embedded Web Server Technology is most evolving technology for Internet Devices. There are
many application areas including internet devices, telecommunication devices, measuring
instruments and lots of consumer electronics. An embedded web server is a HTTP protocol stack
that is limited to handling HTTP requests. In contrast, an embedded application server is a
software framework dedicated to the efficient execution of programs, routines, or scripts for
supporting the construction of various applications. An application server also contains a web
server. Thus, one may consider a web server a subset of an application server. While a web
server mainly deals with sending HTML for display in a web browser, an application server
provides access to server side logic (server applications) for use by client application programs.
An embedded web server is regarded as a component of a software system that implements
the HTTP protocol. Examples of usage within an application might be:
To provide a thin client interface for a traditional application.
To provide indexing, reporting, and debugging tools during the development stage.
To implement a protocol for the distribution and acquisition of information to be displayed in
the regular interface — possibly a web service, and possibly using XML as the data format.
To develop a web application
The advantages of using HTTP are
HTTP is a well studied cross-platform protocol and there are mature implementations freely
available.
HTTP is seldom blocked by firewalls and intranet routers.
HTTP clients (e.g. Web browsers) are readily available with all modern computers.
There is a growing tendency of using embedded HTTP servers in applications that parallels
the rising trends of home-networking and ubiquitous computing.
Natural limitations of the platforms where an embedded HTTP server runs contribute to the list
of the non-functional requirements of the embedded, or more precise, embeddable HTTP server.
Some of these requirements:
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"Small" RAM and ROM footprint. The exact size depends on the system, but in many cases
anything over several megabytes is not embeddable.
Minimal CPU utilization.
Cross compilation support for multiple CPU and operating system combinations.
Easy integration with an existing application, including static linking with the operating
system and application.
Serving pages from application memory if there is no file system.
Modularity.
Client server model
There are two primary actors when communicating over the web, the server and the client.
Client—A logical entity that initiates a request for data or for an action to take place. A client
depends upon the presence of an associated server to perform requests. A client may refer to
client software, client hardware, or a combination of the two to implement a logical client.
Server—A complementary logical entity to a client. A server listens for client requests and
services those requests, whether the request is for data or for an action to be performed. A
server may refer to server software, server hardware, or a combination of the two used to
implement a logical server
For right now think of the server and the client as two desktop computers. The server
computer waits for the client computer to initiate communication and then the client
computer makes a request for information If the server computer understands the request it
replies with a response else it doesn’t reply back to the. This pattern is called the client-
server.
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The client–server model is a distributed application structure that partitions tasks or workloads
between the providers of a resource or service, called servers, and service requesters,
called clients. Often clients and servers communicate over a computer network on separate
hardware, but both client and server may reside in the same system. A server host runs one or
more server programs which share their resources with clients. A client does not share any of its
resources, but requests a server's content or service function. Clients therefore initiate
communication sessions with servers which await incoming requests. Email, network printing,
and the World Wide Web are examples of client server pattern. As in the figure this pattern uses
the request response message exchange pattern. It is a simple yet powerful method of messaging
which allows two applications to have two way conversations with one another over a channel
The client–server characteristic describes the relationship of cooperating programs in an
application. The server component provides a function or service to one or many clients, which
initiate requests for such services. Whether a computer is a client, a server, or both, is determined
by the nature of the application that requires the service functions. For example, a single
computer can run web server and file server software at the same time to serve different data to
clients making different kinds of requests. Client software can also communicate with server
software within the same computer A server may receive requests from many different clients in
a very short period of time. Because the computer can perform a limited number of tasks at any
moment, it relies on a scheduling system to prioritize incoming requests from clients in order to
accommodate them all in turn
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The following is an apt example of client server model -When a bank customer accesses online
banking services with a web browser (the client), the client initiates a request to the bank's web
server. The customer'slogin credentials may be stored in a database, and the web server accesses
the database server as a client. An application server interprets the returned data by applying the
bank's business logic, and provides the output to the web server. Finally, the web server returns
the result to the client web browser for display. In each step of this sequence of client–server
message exchanges, a computer processes a request and returns data. This is the request-response
messaging pattern. When all the requests are met, the sequence is complete and the web browser
presents the data to the customer
HTML and XML
HyperText Markup Language, commonly referred to as HTML, is the standard markup
language used to createweb pages.[1] Web browsers can read HTML files and render them into
visible or audible web pages. HTML describes the structure of a website semantically along with
cues for presentation, making it a markup language, rather than a programming language. HTML
elements form the building blocks of all websites. HTML allows images and objects to be
embedded and can be used to create interactive forms. It provides a means to create structured
documents by denoting structural semantics for text such as headings, paragraphs, lists, links,
quotes and other items. The language is written in the form of HTML elements consisting
of tags enclosed in angle brackets (like<html>). Browsers do not display the HTML tags and
scripts, but use them to interpret the content of the page. HTML can embed scripts written in
languages such as JavaScript which affect the behavior of HTML web pages
Extensible Markup Language (XML) is a markup language that defines a set of rules for
encoding documents in a format which is both human-readable and machine-readable. It is
defined by the W3C's XML 1.0 Specification[2] and by several other related specifications,[3] all
of which are free open standards.[4] The design goals of XML emphasize simplicity, generality
and usability across the Internet.[5] It is a textual data format with strong support via Unicode for
different human languages. Although the design of XML focuses on documents, it is widely used
for the representation of arbitrary data structures[6] such as those used in web services
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CHAPTER 3
EWT-EXPLAINATIONEmbedded Systems have traditionally been developed in a highly customized manner. The user
interface hardware and software along with the interface to the embedded system are typically
unique to the system for which they are built, resulting in extra cost to the system in terms of
development time and maintenance effort. World Wide Web standards have been developed in
the past ten years with the goal of allowing servers and clients to interoperate seamlessly. The
client and server systems can consist of differing hardware and software platforms but the World
Wide Web standards allow them to interface without knowing about the details of system at the
other end of the interface. Embedded Web Technology is the merging of Embedded Systems
with the World Wide Web. Embedded Web Technology decreases the cost of developing and
maintaining the user interface by allowing the user to interface to the embedded system through
a web browser running on a standard personal computer. Embedded Web Technology can also
be used to simplify an Embedded System’s internal network.
Embedded Web Technology was developed for the Fluids and Combustion Facility (FCF) of
the International Space Station (ISS). FCF is being developed to perform investigations in
combustion science and fluids physics in the microgravity environment of the ISS The World
Wide Web is based on the Hypertext Transfer Protocol (HTTP), the protocol used by web
servers and web browsers to communicate The FCF software engineers did an extensive search
to find an HTTP compliant web server that would fit the requirements of FCF. FCF, being an
embedded, realtime system, would require the web server to be small, operate under VxWorks®,
and still allow the system to meet its real-time requirements. The search failed to find such a web
server. The FCF software engineering team decided to write their own web server and this
proved successful. The web server, known as Tempest, is HTTP compliant. It implements two
of the seven request methods defined in the HTTP specification, GET and HEAD
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Comparison of a typical web server environment versus an embedded, real-time environment A typical web server runs on a computer that is running a nonrealtime operating system. The
web server software itself tends to be large and complex and requires a lot of memory and disk
space, on the order of 10 MB or more. The web servers are designed to run on personal
computers and general purpose workstations. The embedded, real-time environment is much
more restricted. The system generally consists of an embedded processor running a real-time
operating system and also running a real-time application. Embedded systems have limited
memory and disk space that is not easily extensible. The users of these two environments have
different needs of the systems. The user of the nonrealtime environment is usually interested in
obtaining static or slowly changing information. This information is stored in files and retrieved
by the web browser for display by the user. The user can read the information on the display at
his own pace or print it out and read it without the aid of the browser. A user of a real-time
system, on the other hand, is interested in obtaining the most current data from the system at
regular intervals. The user may require the capability to issue commands to the embedded
system.
Overview of the world wide web
The World Wide Web is a collection of protocol standards that are controlled by the World Wide
Web Consortium®. The protocol standards promote evolution of the World Wide Web and
ensure its interoperability. The key protocol standard behind the World Wide Web is the
Hypertext Transfer Protocol, HTTP, specified in RFC 2616. HTTP is “an application-level
protocol for distributed, collaborative, hypermedia information systems.” (RFC 2616). HTTP is
used to transfer information between a web server and a web client, which is typically a web
browser such as Netscape. A typical web client request of a service from a web server will
consist of a GET request. The web server responds to the GET request from the web client by
transmitting the requested information, typically an electronic file
.
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Putting embedded systems on the web
There are two problems that need to be solved in order for an embedded system to become
accessible on the World Wide Web. One is providing a user interface that provides the real-time
interaction needed by the user in order to properly interface to the system. The other is to give
the embedded system the capability to serve web pages over the World Wide Web. One feature
of the web browser that helped bridge the gap between the two environments is the addition of
Java™ applets. Applets are programs that are capable of being executed by a web browser. They
are written in the Java™ language, compiled and then stored on the web server’s computer.
When a web page is transmitted to a web browser, the web browser scans through the web page,
looking for, among other things, applet tags.
When an applet tag is found, the web browser automatically makes another request to the web
server for the applet. The applet gets sent to the web browser which in turn loads the Java™
Virtual Machine which starts running the applet. In the typical web environment, applets
provide an interface that is dynamic but usually does not interact with the web server’s computer.
For security purposes, applets are very restricted in what they can do in a web browser
environment. It is possible to bypass these restrictions with security certificates if they are an
impediment. One capability an applet has by default is the ability to communicate back to the
computer that served it to the web browser. This communication can be accomplished with basic
socket technology, Java’s™ Remote Method Invocation (RMI), Common Object Request Broker
Architecture (CORBA®) technology, or other protocols. RMI is a communication technology
specific to Java™ that allows networked Java™ programs to interface in a platform independent
manner. CORBA®, developed by the Object Management Group™, is a technology that allows
networked programs to communicate in a common manner that is independent of the underlying
hardware, operating system or language. With this capability, it is possible to develop an applet
that can interact dynamically with an embedded, real-time system and, thus, let the web browser
provide a user interface that meets the needs of the user. On the embedded system side, the
problem is providing the capability to be a web server without overburdening the system with all
of the functionality specified in the HTTP specification. The embedded system software still
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needs to be able to perform realtime command and control. This problem was solved by the
development of Tempest.
Tempest features
The Tempest software, which was written by software engineers at the NASA Glenn Research
Center in Cleveland, Ohio, is a web server written specifically for embedded, real-time systems.
Tempest was originally written for the VxWorks® operating system from Wind Rivers Systems,
Inc. and then ported to the Java™ language so that it can run on any operating system that has a
Java™ Virtual Machine. Tempest requires fewer memory resources than web servers written for
the typical web server environment. Memory requirements are under 100 KB, depending on
how it is configured. The amount of disk space is also under 100 KB with additional space
needed for the files that make up the web pages, images and applets. Since Tempest is not
intended to operate as a general purpose web server, it is not necessary to implement the entire
HTTP specification. Only the GET and HEAD request methods from the HTTP specification are
implemented. Methods that allow a web browser to write to the web server are not implemented.
The responses generated by Tempest are also limited to those that an embedded system would
need. Tempest can also be run at a lower priority than other application software running in the
embedded system. Requests from web browser are very brief so Tempest can serve web pages
and other resources at an acceptable speed without having an impact on system performance . An
optional capability requires the user to have an identification and password in order to gain
access to the system. This provides a limited level of security to the system. Other security
features such as firewalls and virtual private networks can be added without changing the
embedded system. It is much easier to have the security features added on as separate entities
rather than built into the system. This allows for easier upgrades to the security system and
decouples the security from the embedded system. The user I.D.’s and passwords are stored in an
external file. New users can be added to the system without having to recompile Tempest. A
configuration file that allows Tempest to associate a user with a specific image file is another
feature. This allows a user to set up the system so that when a remote user gains access to the
embedded system, the web page can be customized to that user on the fly by displaying an image
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file created for that specific user. Tempest also has configuration files that allow the user to
specify which remote clients have access to the embedded system
All of the configuration files are read in by Tempest when it starts up. Tempest first reads in a
file called tempest.sys that contains a list of the configuration files. Updates to any of the
configuration files require the system to be restarted before the changes take effect. Web
browsers are denied access to any file with a “.sys” extension. If the configuration files use this
extension, it is not possible for the person using the web browser to have them displayed.
Tempest will not process any request that contains “..”. The “..” (double dot) is used on most
computer systems to refer to the parent directory on the disk. By not allowing this, it is not
possible for remote users to snoop around the system. Tempest has a feature known as Server
Side Includes (SSI). SSI is the ability of the web server to dynamically alter a web page at the
time of request. Tempest accomplishes this by reading through any file the has an extension of
“.sht”, “.shtm” or “.shtml” and searching for <Tempest> tags. These tags are a unique feature of
Tempest. When Tempest encounters one of these tags, it processes the contents of the tag and
substitutes the tag with the result of the processing
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CHAPTER 4
EWT- WORKING The embedded Web system works on the same principle as that traditional Web request-
response system. Web pages from the embedded system (server) are transmitted to the Web
browser (client), which implements the user interface (Presentation layer). Web-enabled
devices use the HTTP (Hyper Text Transfer Protocol) standard protocol to transmit Web
pages from the embedded system to the Web browser, and to transmit HTML (Hyper Text
Markup Languages) form the data from the browser back to the device. The HTTP protocol
engine takes the request from the Web browser and sends it on the TCP/IP. The HTTP
protocol Engine parses the request and sends it to the embedded application for processing.
After producing the results, the embedded application generates the HTML code and feeds it
to the HTTP Engine, which sends it back to the client using TCP/IP.
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With the utilisatin of tempest it is now possible to have an embedded real-time system appear as
a node on the world wide web. The remote user simply needs a computer with a web browser
capable of running a Java™ applet. The remote user only needs to enter the uniform resource
locator (URL) of the embedded system into the browser. The embedded system needs to be up
and running. Minimally, it needs to have Tempest running and an application to interface to the
system and handle requests from the user interface. The web browser sends an HTTP message to
the embedded system, requesting the web page. If the user needs to enter a user I.D. and
password, Tempest responds with a request for the user to be authenticated. Once the user is
authorized, Tempest retrieves the web page from local storage. If the file has an extension of
“.sht”, “.shtm”, or “.shtml”, Tempest reads through the file and processes any Tempest tags
When this step is complete, the web page is delivered to the web browser. The web browser
displays the web page and also requests any additional resources from the embedded system.
These resources may include images and an applet. When the applet gets sent to the browser, the
browser starts up its Java™ Virtual Machine which starts up the applet. The applet establishes a
connection back to the embedded system, utilizing a different TCP port form the one being used
by Tempest, which is typically 80. While the connection is being established, the applet also
begins the user interface. Since Java™ supports multitasking, the applet should be designed so
that the user interface screens run in a separate task from the interface to the embedded system.
This gives a smoother running interface and also makes it easier to recover from communication
drops without locking the user out
CHAPTER5
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ADVANTAGES
Utilizing Embedded Web Technology has several advantages. Since the web browser does not store the applet permanently, the user interface software is not accessible to unauthorized users once the web browser is turned off. It is possible to configure present day web browsers to eliminate the cache so that the applet gets deleted. User interface software upgrades are simpler with Embedded Web Technology. Without Embedded Web Technology, the user of the real-time system also needs to have the user interface software stored locally. The result is that the user is restricted to using only the computer that has the user interface software loaded and upgrades to the software can be more difficult to obtain. The updates require the user to find out about the upgrade and then a process needs to be put in place to deliver the upgraded software to the user. The upgraded software may also need to be capable of running on various platforms, making upgrades more difficult for the developer. With Embedded Web Technology, the user interface software is stored in the embedded system and delivered to the user when it is needed. When the user interface software is upgraded, it only needs to be stored in the embedded system. The user gets the new software the next time they access the system. Tempest also provides the capability to provide output to the remote user in any format the system designer desires. Although the Tempest tag is typically embedded into a web page that is html, it is possible to set up a file that consists of only a Tempest tag calling a local command that outputs something other than html, such as XML. As an example, Tempest could be used to feed real-time data into a database using XML.
CHAPTER 6
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APPLICATIONS
Traffic monitoringWith rapid economic development and transportation has increasingly become an important
component in the national economy and daily life. So it is necessary to build a modern intelligent
traffic control system in order to resolve the traffic congestion on roads and reduce accidents. It
contains embedded Linux operating system, design of embedded web server, transplantation of
database and implementing method of main functions. Remote monitoring is realize to
monitoring traffic conditions, traffic control, information published and communication of traffic
data by using combining embedded web server (EWS) technology with Internet. The results
specify that the intelligent traffic control technology based on embedded web technology can
accomplish the integration of a wide range of information collection and it breaks through the
established traffic monitoring technology for designing traffic monitoring system
Video monitoring
Applied the embedded Web technology in the field of equipment condition monitoring, the
equipment remote monitoring system is designed based on embedded Web an embedded web-
based remote monitoring system for video images Starting from small houses to big industries,
now video surveillance is necessary and plays very important role to fulfill our security aspects
in many ways. In this paper video monitoring system is designed bases on real time operating
system
Power infrastructure monitoring
he PIMS system is needed for monitoring of power being used by remote equipment such as cell
tower. The PIMS agent consisting of high resolution ADC and microcontroller monitors the
current and voltages being consumed and sends the data over GPRS to the centralized server.
The server collects the data, stores it in database and uses it for analysis. The server provides
modularity as well as scalability. A server can handle multiple PIMS agents. The monitoring
helps to determine the power use as well as it also enables the user to identify the malfunction of
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EMBEDDED WEB TECHNOLOGY
the system remotely. It also eliminates the need of onsite operator as well as server operator.
With increasing power crisis, this system helps to monitor the power use and helps proper
utilization of power.
CHAPTER 7
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EMBEDDED WEB TECHNOLOGY
CONCLUSIONS
Embedded Web Technology provides for the development of an embedded, real-time system that
appears to the users of the system as a node on the World Wide Web. This capability provides
for great savings by eliminating the need to develop and distribute user interface software that is
platform specific and somewhat cumbersome to configuration manage. Tempest software is a
small, flexible web server that makes it easy to interface to embedded systems. It also has the
potential to be an aid in debugging systems. Tempest workshops have been held for customers in
the private sector. Customer remote data acquisition and control applications include medical,
telecommunications, aerospace, factory automation, instrumentation, automotive, building
management and education.
.
REFERENCES
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1. Embedded Web Technology: Applying World Wide Web Standards to Embedded Systems- Joseph G. Ponyik and David W. York Glenn Research Center, Cleveland, Ohio; NASA/TM—2002-211199/March 2002/AIAA–2001–5107
2. Embedded web technology in traffic monitoring system, International Journal of Innovative Research in Advanced Engineering (IJIRAE) Volume 1 Issue 4 (May 2014 ISSN: 2349-2163 ) http://ijirae.com
3. Application Research of Embedded Web Technology in Traffic Monitoring System Proceedings of the Second Symposium International Computer Science and Computational Technology(ISCSCT ’09) Huangshan, P. R. China, 26-28,Dec. 2009, pp. 094-097
4. Power infrastructure monitoring system on Embedded Web International Journal of Science and Engineering
5. Volume 1, Number 2 - 2013 PP-71-76 ©IJSE6. Dustdar, S.; Schreiner, W. (2005). "A survey on web services
composition". International Journal of Web and Grid Services 1: 1. Doi:10.1504/IJWGS.2005.007545.
7. Li Shenyang, HanTao,”Application of embedded WEB server technology” [J]. Journal of higher correspondence education (natural sciences) 2003, (6) Vol. 16 No. 3: 47-50.
8. Han XiaoTao,Yin XiangGen, Zhang Zhe, LI Wei, ” Review of embedded web server technology and its application in power system” Power System Technology 2003,(5): 58-62
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