Domain Name System and Dynamic Host Configuration Protocol

Domain Name System (DNS)

Domain Name System (DNS) is a system that allows name of a host on a computer network or the Internet translated into IP addresses. In giving the name, the DNS uses architectural hierarchy:
a) Root-level domains: is the top level of the displayedas a dot (.).

b) Top-level domains: code category or state organizations such as: . com for use by the company;. edu for use bycollege;. gov for use by government agencies. In addition 22 was to distinguish the use of name by a country with Other countries use such marks. id to Indonesia or. au to Australia.
c) Second-level domains: is the name for the organization or company, for example: microsoft.com, yahoo.com, etc.

DHCP (Dynamic Host Configuration Protocol)

IP address and subnet mask can be given automatically using the Dynamic Host Configuration Protocol, or filled manual. DHCP function to provide IP addresses automatically on a computer that uses TCP / IP protocols. DHCP works with client-server relationship, where the DHCP server provides a groups of IP addresses that can be given to the DHCP client. In This gives the IP address, DHCP lends an IP address only them. So giving the IP address takes place dynamically.

IP Address Classes

To simplify usage, depending on the needs of users,
IP addresses are divided into three classes as shown below
Class Network ID Host ID Default Subnet Mask
A xxx.0.0.1 xxx.255.255.254 255.0.0.0
B xxx.xxx.0.1 xxx.xxx.255.254 255.255.0.0
C xxx.xxx.xxx.1 xxx.xxx.xxx.254 255.255.255.0
IP addresses are given for the class A network with a number of hosts
very large. IP Range 1.xxx.xxx.xxx. - 126.xxx.xxx.xxx, there
16,777,214 (16 million), an IP address in each class A. In the IP address class
A, the network ID is the 8 bit first, while the host ID is 24 bits
next. Thus, how to read the IP address class A,
for example 113.46.5.6 is:
Network ID = 113
Host ID = 46.5.6
IP address numbers above mean 46.5.6 host on the network number 113.
IP addresses are usually allocated to class B-sized networks
medium and large. In class B IP address, network ID is 16 bits
21
First, while the host ID is 16 bits next. Thus,
how to read a class B IP address, for example, 132.92.121.1:
Network ID = 132.92
Host ID = 121.1
IP host address above mean number 121.1 on the network number 132.92.
With a length of 16-bit host ID, network with IP address class B to
accommodate about 65,000 hosts. IP Range 128.0.xxx.xxx -
191.155.xxx.xxx.
Class C IP address originally used for small networks
(LAN). Host ID is 8 bits last. With this configuration, can be formed
about 2 million networks with each network has 256 IP
address. IP Range 192.0.0.xxx - 223.255.255.x.
The allocation of IP address is basically the process of selecting the network ID
and host ID is right for a network. Appropriate or not
This configuration depends on the objectives to be achieved, namely
allocate an IP address as efficiently as possible.

Network Type

The network type associated with the network operating system. There are two types  network, ie client-server and peer to peer type network.

a) Client-Server Networks 

Servers are computers that provide facilities for komputerkomputer  others in the network and the client is a computer-computer  who receive or use the facilities provided by the server.  Server in client-server type of network called a Dedicated Server  because the pure act as servers that provide facilities to  workstations and servers can not serve as  workstation.  

Excellence

· Higher access speeds due to the provision of network facilities and  management is carried out exclusively by a single computer (server)  that is not burdened with other tasks such as workstations.
· Security systems and network administration is better, because  there is a computer that served as the administrator network, which manages the administration and network security systems.
· Data backup system is better, because on a client-server network backups performed centrally at the server, which will backup all data used in the network.

Weakness

· Cost is relatively more expensive operation.

· Required the presence of one particular computer which enabled more to be assigned as a server.
· Tissue viability depends on the server. When the server  impaired the overall network will
disturbed.16

b) Peer To Peer Network

When viewed from a server role in both types of networks, the  server in the network of peer to peer type is termed non-dedicated server,  because the server does not act as a pure server but at the same time  can serve as workstation.

Excellence

· Inter computers in the network are able to share facilities  who has such as: hard drive, drive, fax / modems, printers.
· Cost relatively cheap operation compared with the type  client-server network, either because they do not require any  server that has a special ability to organize and provide networking facilities.
· Viability of the network is not dependent on a single server.  So if one computer / peer dead or damaged tissue as a whole will not experience interference.

Weakness

· Troubleshooting network is relatively more difficult, because the tissue type  peer to peer every computer it is possible to engage in  existing communications. In client-server network, communication is between the server and workstation.

· The performance is lower compared to client-server network,  because every computer / homework in addition must manage the use of  network facilities also have to manage the job or the application itself.
· Network security system is determined by each user  to regulate the safety of each facility owned.
· Since data networks spread in each computer in  network, the backups should be performed by each computer them.

The types of tissue

In general, a computer network consists of five types:

a) Local Area Network (LAN), a privately owned network in the a building or campus-sized to several kilometers. LANs are often used for connecting computers personal and workstation in the office of a company or pabrikpabrik to use common resources (resouce, such as printers) and exchange information.

 

b) Metropolitan Area Network (MAN)

Metropolitan Area Network (MAN), basically a LAN version larger and typically use technologies same LAN. MAN can include company offices located adjacent or also a town and can be used for private purposes (private) or public. MAN can support data and voice, even may be associated with television network cable.

 

c) Wide Area Network (WAN), its scope covers the area geographical area, often covering a country or even continent. WAN consists of a collection of machines aimed at running programs (applications) user.

 

d) Internet 

Actually there are many networks in the world, often use hardware and software that is different. People who connect to the network often wish to be communicate with others who connect to other networks. This desire requires the relationship between network often not compatible and different. Usually to do this 11 This required a machine called a gateway in order to perform relationship and perform the necessary translation, both hardware and software. Collection network interconnected is called the Internet.

 

e) Wireless (Wireless Network), a wireless network a solution to komukasi that can not be done with network cables. For example, people who want to get information or to communicate despite being located above car or plane, then the absolute network without wires necessary because the cable connection is not possible to be made in the car or aircraft. Currently, wireless networks have rapidly adopted by making use of satellite services and is able to provide speed faster access than the networks using cable.

Internet protocol

Internet protocol (IP) is in the layer internetwork or internet. IP is the key TCP / IP network must rely on internet protocol.

IP protocol has five main functions, namely:
1. Defining a package that became the smallest unit of data transmission on the Internet
2. Transferring data between the Transport layer and network interface layer
3. Defining the Internet addressing scheme or IP address
4. Determining routung package
5. Melaakukan packet fragmentation and re-drafting