1. NAME:- MOHD. SHAHNAWAZ ALAM
ROLL NO:-
COURSE:-B.SC (IT)
SEMESTER: - THIRD
BOOK NO:- BT0078(WEBSITE DESIGN)
SESSION:- SPRING 2012
1. What are the requirements for an internet connection?
you have to have a modem, a phone line / LAN cable wire/ and a wireless router (if you plan to
use wireless connection). Make sure you have an ISP (internet service provider) If you would
like to get access to the internet at home, you'll need an Internet Service Provider (ISP) and a
modem to connect to the ISP. ISPs often provide a device called a router to let you share an
internet connection over a local area network, which means more than one computer in your
house can use the broadband connection at the same time. The devices are connected with
cables and a hub or switch.
A good place to start looking for an ISP is the Internet Service Provider Association (ISPA).
Although this is a voluntary body it's recognised by government for its knowledge and
expertise. All ISPs listed on the ISPA site have agreed to certain rules and standards set by the
ISPA. This means you can be confident an ISP listed by ISPA has good business practice.
Similarly, you might find it helpful to get recommendations from friends who have an ISP as
there is no better substitute for getting a recommendation from someone you trust. If you are
going to look for the ISP on your own try to get as much information as you can about what
they offer.
2. Briefly explain the transparent graphics.
Transparency is possible in a number of graphics file formats. The term transparency is used in
various ways by different people, but at its simplest there is "full transparency" i.e. something
that is completely invisible. Of course, only part of a graphic should be fully transparent, or there
would be nothing to see. More complex is "partial transparency" or "translucency" where the
effect is achieved that a graphic is partially transparent in the same way as colored glass. Since
ultimately a printed page or computer or television screen can only be one color at a point, partial
transparency is always simulated at some level by mixing colors. There are many different ways

2. to mix colors, so in some cases transparency is ambiguous.In addition, transparency is often an
"extra" for a graphics format, and some graphics programs will ignore the transparency.
Transparent Pixels: One color entry in a single GIF or PNG image’s palette can be defined as
"transparent" rather than an actual color. This means that when the decoder encounters a pixel
with this value, it is rendered in the background color of the part of the screen where the image is
placed, also if this varies pixel-by-pixel as in the case of a background image.
Applications include:
· An image that is not rectangular can be filled to the required rectangle using transparent
surroundings; the image can even have holes (e.g. be ring-shaped)
· In a run of text, a special symbol for which an image is used because it is not available in the
character set, can be given a transparent background, resulting in a matching background.
The transparent color should be chosen carefully, to avoid items that just happen to be the same
color vanishing.
Even this limited form of transparency has patchy implementation, though most popular web
browsers are capable of displaying transparent GIF images. This support often does not extend to
printing, especially to printing devices which do not include support for transparency in the
device or driver. Outside the world of web browsers, support is fairly hit-or-miss for transparent
GIF files.
4. Explain the Domain Name System and DNS servers.
The DNS translates Internet domain and host names to IP addresses. DNS automatically
converts the names we type in our Web browser address bar to the IP addresses of Web
servers hosting those sites.DNS implements a distributed database to store this name and
address information for all public hosts on the Internet. DNS assumes IP addresses do not
change (are statically assigned rather than dynamically assigned).The DNS database resides
on a hierarchy of special database servers. When clients like Web browsers issue requests
involving Internet host names, a piece of software called the DNS resolver (usually built into
the network operating system) first contacts a DNS server to determine the server's IP
address. If the DNS server does not contain the needed mapping, it will in turn forward the
request to a different DNS server at the next higher level in the hierarchy. After potentially
several forwarding and delegation messages are sent within the DNS hierarchy, the IP
address for the given host eventually arrives at the resolver, that in turn completes the
request over Internet Protocol.DNS additionally includes support for caching requests and
for redundancy. Most network operating systems support configuration of primary,
secondary, and tertiary DNS servers, each of which can service initial requests from clients.
Internet Service Providers (ISPs) maintain their own DNS servers and use DHCP to
automatically configure clients, relieving most home users of the burden of DNS
configuration.

3. 5. Explain the use of client-side image maps.
Image maps aren’t as bad as they seem, at least if you use a client side image map using HTML
rather than a CGI program. Now you need to put the image on the page. To do this, you use the
image tag, but with a new attribute: usemap.
<img src="eximap1.gif" width="200" height="40" border="0" alt="image map"
usemap="#mymap" />
The usemap="#mymap" command tells the browser to use a map on the page, which is named
"mymap". Notice how it uses the "#" symbol in front of the map name. Also notice that we
defined the width and height of the image. This need to be done so we can use coordinates later
on when we define the map. Speaking of that, let’s see how to define the map. For this map, we
would place the following code somewhere on the page.
<map name="mymap" id="mymap">
<area shape="rect" coords="0, 0, 99, 40" href="table1.htm" alt="Tables" />
<area shape="rect" coords="100, 0, 200, 40" href="frame1.htm" alt="Frames" />
<area shape="default" href="http://www.pageresource.com" alt="Home" />
</map>
Now you can see where the usemap="#mymap" from the <img> tag comes from. The name of
the map is "mymap". Now, let’s look at what all of this means:
<map name="mymap" id="mymap">
This defines your image map section, and gives the map a name. This map is named "mymap" In
XHTML, the id attribute is required rather than name. If you are using XHTML transitional, both
the name and id can be used.
<area shape="rect" coords="0,0,99,40" href="table1.htm" alt="Tables" />
The area tag defines an area of the image that will be used as a link. The shape attribute tells the
browser what shape the area will be. To keep it simple, I only used "rect", which stands for
rectangle. The coords attribute is where we define the edges of each area. Since it is a rectangle,
we will use two sets of coordinates. The first set defines where to start the rectangle, where the
top-left edge of the rectangle will be. Since this rectangle starts at the top-left edge of the image,
the coordinates are (0 pixels, 0 pixels). The second two numbers define where to end the
rectangle. This will be the lower-right edge of the rectangle. Remember that the total image size
was 200×40. We want the lower-right edge of this rectangle to be halfway across the image and
at the bottom of the image. Going across, half of 200 is 100, but we use 99 here because 100 can
only be used once. We will use it in the second rectangle here. Of course, 40 pixels take us to the
bottom of the image. So the lower-right corner of this rectangle will be 99 pixels across the
image, and 40 pixels (all the way) down the image. And now the easy part: The href attribute is
used to tell the browser where to go when someone clicks someplace on that rectangle. Put the

4. URL of the page you want to go to in there, and the first rectangle is set up! The alt attribute
allows you to define alternate text for that area.
<area shape="rect" coords="100, 0, 200, 40" href="frame1.htm" alt="Frames" />
Basically the same as the previous area tag, but it is for our second rectangle. We start where the
other one left off, but back at the top of the image. Since the right edge of the last rectangle was
at 99 pixels accross, we start this one at 100 pixels accross. And since this will be the upper-left
of the second rectangle, we start it at 0 pixels down the image (the top!). We end this rectangle
where the image ends, so the lower-right coordinate here is pretty nice- (200, 40), the size of the
image!
<area shape="default" href="http://www.pageresource.com"
alt= "Home">
The default is not really a new shape; it just covers anything that may have been left out. We
didn’t leave out anything in this map, but if we had, this would be the URL someone would go to
if they clicked on any area we did not define earlier.
</map>
This ends the map section!
Now, you can use other shapes besides rectangles, but those are a lot tougher to code by hand.