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For human consumption, we usually convert the value of each of the bytes to an unsigned decimal value and display them connected by periods to make themeasier to remember. For example, as near as I can tell, as of this writing, the IP address of www.austincc.edu (the college where I teach) is 206.77.150.222 .

Domain Names

What do I mean by www.austincc.edu ?

Even though we can do some tricks to make the numeric IP addresses easier to remember, humans don't do a very good job of remembering long stringsof numbers. Humans remember words and names better. Therefore, most IP addresses have a corresponding name known as a domain name . The domain name for the IP address 206.77.150.222 is www.austincc.edu .

The Domain Name System (DNS) was developed to translate between IP addresses and domain names. Whenever you log your browser onto the internet and attempt to connect to a server using its domain name, the browser firstcommunicates with a DNS server to learn the corresponding numeric IP address. The numeric IP address (and not the domain name) is encapsulated into the data packets and used by the internet protocol to routethose packets from the source to the destination.

(You should also be able to enter 206.77.150.222 into the address field of your browser and access the college where I teach.)

We will learn how to use the Java InetAddress class to find the domain name corresponding to an IP address, and to find the IP address corresponding to a domain name.

What is Your IP Address?

Do you have an IP address and a domain name ?

If (like me) you use a commercial Internet Service Provider (ISP) for your Internet service at home,you probably don't have a fixed IP address or a fixed domain name . Rather, the ISP has a block of IP addresses reserved. When you subscribe to the ISP, the ISP temporarily assigns an IP address to you. That IP address may or may not change over time, but probably will change unless youpay the extra fee for a fixed IP address.

On the other hand, I currently pay for server space from a company in North Carolina under thedomain name www.dickbaldwin.com . My domain has an IP address of 98.129.229.162 . For as long as I continue to pay the bill, that domain name and that IP address will be assigned to me foruse as my personal website.

I suppose that the company could change the IP address at some point provided that they make certain that all of the domain name servers get updatedto reflect the new IP address that corresponds to the domain name.

Ports

Each server computer that you may connect to will be logically organized into ports . These are not physical ports in the sense of the VGA or HDMI port onthe back of your computer. Rather, they are simply logical sub-addresses which you provide to the operating system on the server so that the operating systemcan cause the appropriate server software to "answer the call." We will write a simple server software package that will service several different ports onindependent threads in a future module.

One of the Java books on my bookshelf refers to the IP address as being analogous to the telephone number of a company and the port to be analogous to the employee's telephone extension within that company. (At least that is how telephone systems in companies were organized when I was working in industry.)

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Object-oriented programming (oop) with java. OpenStax CNX. Jun 29, 2016 Download for free at https://legacy.cnx.org/content/col11441/1.201
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