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Kamis, 25 Oktober 2012
Cabling type Lan
Cabling type Lan
Several physical data-transmission media are available to connect together the various devices on a network. One possibility is to use cables. There are many types of cables, but the most common are:
Coaxial cable
Double twisted pair
Optical fibre
Coaxial cable
Coaxial cable has long been the preferred form of cabling, for the simple reason that it is inexpensive and easily handled (weight, flexibility, ...).
A coaxial cable is made of up a central copper wire (called a core) surrounded by an insulator, and then a braided metal shield.
The jacket protects the cable from the external environment. It is usually made of rubber (or sometimes Polyvinyl Chloride (PVC) or Teflon).
The shield (metal envelope) surrounding the cables protects the data transmitted on the medium from interference (also called noise) that could corrupt the data.
The insulator surrounding the central core is made of a dielectric material that prevents any contact with the shield that could cause electrical interactions (short circuit).
The core, which actually transports the data, generally consists of a single copper strand or of several braided strands.
Thanks to its shield, coaxial cable can be used over long distances at high speed (unlike twisted pair cable), however it is usually used for basic installations.
Note that there are also coaxial cables that have a double shield (one insulating layer, one shield layer) and coaxial cables with four shields (two insulating layers, two shield layers).
Normally, two types of coaxial cable are used:
10Base2 - thin coaxial cable (called Thinnet or CheaperNet) is a thin cable (6 mm in diameter), that is white (or grayish) by convention. It is very flexible and can be used in most networks by connecting it directly to the network card. It is able to transport a signal up to around 185 metres without line loss.
It is part of the RG-58 family whose impedance (resistance) is 50 ohms. The different types of thin coaxial cables are differentiated by the central part of the cable (core).
Cable Description
RG-58 / U Central core consisting of a single copper strand
RG-58 A/U Braided
RG-58 C/U Military version of RG-58 A/U
RG-59 Wide band transmission (cable television)
RG-6 Thicker diameter, recommended for higher frequencies than RG-59
RG-62 Arcnet Network
10Base5 - thick coaxial cable (Thicknet or Thick Ethernet and also called Yellow Cable, because of its yellow colour - by convention) is a shielded cable with a thicker diameter (12 mm) and 50 ohm impedance. It was used for a long time in Ethernet networks, which is why it is also known as "Standard Ethernet Cable". Given that it has a larger-diameter core, it is able to carry signals over long distances: up to 500 meters without line loss (and without signal reamplification). It has a bandwidth of 10 Mbps and is very often used as a backbone to connect networks whose computers are connected with Thinnet. However, because of its diameter, it is less flexible than Thinnet.
Transceiver: the connection between Thinnet and Thicknet
Thinnet and Thicknet are connected using a transceiver. It is equipped with a so-called "vampire" plug that makes the real physical connection to the central part of the Thinnet by piercing the insulating envelope. The transceiver cable (drop cable) connects to an AUI (Attachment Unit Interface) connector, also called a DIX (Digital Intel Xerox) connector or a DB 15 (SUB-D 15) connector.
Coaxial cable connectors
Thinnet and Thicknet both use BNC (Bayonet-Neill-Concelman or British Naval Connector) connectors to hook up the cables to computers.
The following connectors are in the BNC family:
BNC cable connector: this is soldered or crimped to the end of the cable.
BNC T-connector: this connects the computer's network card to the network cable.
BNC Extender: this joins two coaxial cable segments to form a longer one.
BNC terminator: this is placed at each end of a cable in a Bus network to absorb interference signals. It is connected to earth. A bus network cannot function without them. It would stop working.
Twisted pair cabling
In its simplest form, twisted-pair cable consists of two copper strands woven into a braid and covered with insulation.
Two types of twisted pair cable are generally recognized:
Shielded Twisted Pair (STP);
Unshielded Twisted-Pair (UTP ).
A cable is often made of several twisted pairs grouped together inside a protective jacket. The twisting eliminates noise (electrical interference) due to adjacent pairs or other sources (motors, relays, transformers).
Twisted pair is therefore suitable for a local network with few nodes, a limited budget and simple connectivity. However, over long distances at high data rates it does not guarantee data integrity (i.e. loss-less data transmission).
Unshielded Twisted Pair (UTP)
UTP cable complies with the 10BaseT specification. This is the most commonly used twisted pair type and the most widely used on local networks. Here are some of its characteristics:
Maximum segment length: 100 metres
Composition: 2 copper wires covered with insulation
UTP Standards: determine the number of twists per foot (33 cm) of cable depending on the intended use
UTP: collected in the EIA/TIA (Electronic Industries Association / Telecommunication Industries Association) Commercial Building Wiring Standard 568. The EIA/TIA 568 standard used UTP to create standards applicable to all sorts of spaces and cabling situations, thereby guaranteeing the public homogeneous products. These standards include five categories of UTP cables:
Category 1: Traditional telephone cable (voice but no data transmission)
Category 2: Data transmission up to a maximum of 4 Mbit/s (RNIS). This type of cable contains 4 twisted pairs
Category 3: 10 Mbit/s maximum. This type of cable contains 4 twisted pairs and 3 twists per foot
Category 4: 16 Mbit/s maximum. This type of cable contains 4 copper twisted pairs
Category 5: 100 Mbit/s maximum. This type of cable contains 4 copper twisted pairs
Category 5e: 1000 Mbit/s maximum. This type of cable contains 4 copper twisted pairs
Most telephone installations use UTP cable. Many buildings are pre-wired for this type of installation (often in sufficient number to satisfy future requirements). If the pre-installed twisted pair is of good quality, it can be used to transfer data in a computer network. Attention must be paid, however, to the number of twists and other electrical characteristics required for quality data transmission.
UTP's major problem is that it is particularly susceptible to interference (signals from one line mixing with those of another line). The only solution to this is shielding.
Shielded Twisted Pair (STP)
STP (Shielded Twisted Pair) cable uses a copper jacket that is of better quality and more protective that the jacket used for UTP cable. It contains a protective envelope between the pairs and around the pairs. In an STP cable, the copper wires of one pair are themselves twisted, which provides STP cable with excellent shielding, (in other words, better protection against interference). It also allows faster transmission over a longer distance.
Twisted pair connectors
Twisted pair cable is connected using an RJ-45 connector. This connector is similar to the RJ-11 used in telephony, but differs on a few points: RJ-45 is slightly larger and cannot be inserted into an RJ-11 jack. In addition, the RJ-45 has eight pins while the RJ-11 has no more than six, usually only four.
Fibre optics
Optical fibre is a cable with numerous advantages:
Light-weight
Immune to noise
Low attenuation
Tolerates data rates on the order of 100 Mbps
Bandwidth from tens of megahertz to several gigahertz (monomode fibre)
Fibre optic cabling is particularly suited to links between distributors (central link between several buildings, known as backbone) as it allows connections over long distances (from several kilometres to 60 km in the case of single-mode fibre) without requiring earthing. Furthermore, this type of cable is very secure as it is extremely difficult to tap in to such a cable.
However, despite its mechanical flexibility, this cable type is not suitable for local network connections as it is difficult to install and is very expensive. For this reason, twisted pair or coaxial cable are preferred for short links.
Client computer
Information moved from computer to computer using a network rather than through human intermediaries. So make information exchange easier and faster.
Most basic network has two computers that communicate with each other by cable medium or any other medium. When your computer is connected to another computer, you can move information quickly and efficiently.
In the book "Networking Complete" explained that a bunch of computers and other equipment are connected together is called network, while the concept of the connected computer and share resources (resources) is called networking.
Network Building Blocks
All of the network, be it large or small, require specialized hardware network. For small networks, the hardware may consist of nothing more than a network interface card (NIC) on each computer, cable for each computer and network switch where all the computers are connected. Large networks may be artifacts of additional components such as a router or repeater.
Small or large, all networks are built from the following basic building blocks:
Client computer
Computers are used by end users to access existing resources dijaringan. Client computer is sometimes designated as a workstation.
Computer server
The computer that provides resources used to be together, such as disk storage and printers, as well as network services, such as e-mail and Internet access. Server computers running the operating system in particular specialized tissues such as Windows Server 2003, NetWare, or Linux, as well as special software to provide network services. For example, the server may be running Microsoft Exchange to provide e-mail to the network, or run the Apache Web Server so that computers can serve Web pages.
Network interface card (NIC)
Network interface card installed in the computer allows computers to communicate over a network. Almost every NIC implements networking standard called Ethernet. Each client computer and the server must
has a network interface card (or built-in network port) if you want to be part of the network.
Cable
Computers in a network are usually physically connected to each other by using a cable. Although there are some popular types of cables, wires commonly used today is a twisted pair or also called 10BaseT. Other cable types are also commonly used is coaxial or also called 10Base2. For high-speed network connection, sometimes used fiber-optic cables. In most cases, cable laid through the wall and collected diruangan called central wiring closet. But for smaller networks, cable is usually just laid on the floor.
Switch
Cable networks are usually not connected directly to the computer. Instead, each computer is connected by cable to a device called a switch. Switch, instead, connect to the network. Each switch contains multiple ports, typically 8 or 16. Thus we can use
8 port switch to connect eight computers.
Switches can be connected to each other to build a larger network. Old network might still exist that use a tool called a hub than a switch. Hub provides the same function as a switch but not seefesien switch.
Wireless networks
On the wireless computer network to communicate with other computers via radio signals. In wireless networks, radio transmitter and a radio receiver replacing the cable. The main advantage is the flexibility of the wireless network. With a wireless network, we do not need to pull the wires through the walls or the ceiling, and a client computer can be located anywhere as long as the broadcast network distance. The main disadvantage of the wireless network is less secure than wired network.
Software Network
Despite the critical network hardware, in fact actually running the network is the software. Many software must be set up according to the order for the network to work. Computer servers in particular uses a special operating system network (network operating system or NOS) to function efficiently, and the client computer requires a properly configured network settings in order to access the network.
The purpose and benefits of building a computer network
In building a computer network must have a purpose and benefits that are very helpful to us as follows:
Sharing resources
We can divide the existing resources in the sense that it can be used together as the program, equipment, or other peripherals that enable every person who is on a computer network without having to be affected by the location.
Media communication
May allow for communication between network users, both for teleconferencing, instant messaging, chat, send electronic mail (e-mail) or send other important information.
Data Integration
Can prevent reliance on a central computer, each process data should not be done on one computer but can be distributed to other places or in other words can be done by the other computers in the
tissue.
Security of data
Computer network system can provide protection against data through setting user permissions and passwords, as well as other protection techniques.
Web Browsing
To access information on the network, such as web browsing. Almost everyone who reads this article may never use a web browser (such as Internet Explorer, Mozilla Firefox, Netscape, Opera and others). The web browser enables us to see the information in a web server somewhere on the Internet.
Development and maintenance easy and cost-saving.
For example, a company can save on equipment that must be used.
Network-Based Application
Network is used to provide network services for network users. Applications available networks in general, ie file services, print services, web services, e-mail, file transfer service.
File Service
The computer where the file is stored is called a file server. The other computer (the access) is called the client, and that can be done is to read and write to these files, without the need to create a local copy of the file on the disk drive client. The service is usually transparent to the end user.
Print Service
Printers are connected to a computer called a print server. Client computer can send a file to the print server, which then prints the file to the printer. This server is usually transparent to the user.
Web Service
The server stores a variety of information, including text, graphics, animations, images, video, and audio. End user uses a web browser to request information from a server. The server returns information displayed by the web browser.
End users create e-mail using the e-mail client and send e-mails to a particular person. E-mail server to help the process of sending e-mail.
File Transfer Service
Files are also stored on the server. This server allows a computer (client) to copy the files from the server to their local disk drive and replace the contents of the file on the file server with the files on the local disk drive client.
Classification of computer networks based on area
Computer networks can be classified based on the size of the network area LAN, MAN, WAN.
LAN (Local Area Networking)
Local Area Network is a network of personal property in a single location, usually on one floor of a building, campus, or all the computers in an enterprise. The magnitude of the coverage area of a LAN network can be several kilometers.
MAN (Metropolitant Area Networking)
Metropolitan Area Network is basically a larger version of LAN and generally using the same technology. And coverage may be a group of adjacent branches.
WAN (Wide Area Networking)
Wide Area Network to reach a large geographical area, usually a country or continent.
Computer Networks Based on Role (function)
Based on the role then there are three types of computer networks, the client-server (sometimes also called server-based), peer-to-peer, hybrid network:
Client-Server
That computer networks where the network is there a dedicated computer as a server. The server has a responsibility to provide a service / services provided to other computers.
Common services provided by servers typically provide services such as file services, print services, web services, e-mail, file transfer service. Where will the computer (client) can access the services provided by the server.
Peer-to-peer
Is a network of computers where each computer can be a server and a client simultaneously. For example, the file sharing between computers on the network Windows Network Neighbourhood there are 5 computers (we named A, B, C, D and E) are granted access to the files they have. At one point A to access the file share of B named data_nilai.xls filesoal_uas.doc and also gives access to C. When accessing a file from B then A serves as a client and as a give file access to C then A is acting as a server. Both functions were performed by the same A network like this so called peer to peer.
Hybrid Network
Most of the network is actually in fact a hybrid network. In this network generally have active domains and workgroups. Hybrid network is a network-based client-server which in addition to the network servers provide resources most needed by the user, but the user is still
can access the resources provided by other users (peer-to-peer) in a workgroup.
Network topology
Based on the network topology, computer networks can be distinguished:
Bus Topology
Star Topology
Topology Ring
Mesh Topology (Random)
Topology Tree (Hirarkies)
Linear Topology
Linux Samba
Samba is a software operating system that works on linux, unix and windows that use the network protocol smb (server massage block). Smb is a data communication protocol that is also used by Microsoft and OS / 2 to show the function of a client-server network that provides file and printer sharing and other tasks related.
Samba is able to share files with a computer operating system linux, unix and windows with peer to peer systems. In addition to bridge divide the samba file system functions such as the use of client-server PDC (primary domain control), DHCP (dynamic host configuration protocol), DNS (domain name system), FTP (file transfer protocol), web server, mail server, telnet , ssh and more.
Samba is able to share files with a computer operating system linux, unix and windows with peer to peer systems. In addition to bridge divide the samba file system functions such as the use of client-server PDC (primary domain control), DHCP (dynamic host configuration protocol), DNS (domain name system), FTP (file transfer protocol), web server, mail server, telnet , ssh and more.
Many applications that run on linux and samba thus bridged by linux or unix windows can use it. One example is a firewall application. Firewalls can be configured here as we want, such as the firewall will run when the computer is turned on, when dial-out, or when it gets the ip from the dhcp server.
Other applications that can be bridged running samba is a proxy server using squid. This proxy security functionality can be easily arranged by the purpose, sources and how to access the destination. Samba also has applications swat. That is a web-based application that samba is made to facilitate the samba settings you want.
The following are facilities that can bridge the samba software which are as follows:
a. Sharing files with samba.
b. Use swat.
c. Sharing equipment with samba as printers and others.
d. Setting user and group security configuration such as samba as PDC.
e. DHCP support.
f. Supports DNS.
g. Linux network security settings like firewalls and anti-virus.
h. Use FTP server.
i. Using Webserver.
j. Configuring the Internet gateway.
k. The use of mail server.
l. The use of a proxy server ..
m. Use telnet and ssh
n. And much more.
Function / Usage Samba
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Usability / functionality of Samba in computer networks are:
Linking between Linux machines (UNIX) with Windows machines. As the software is pretty much a function to do the samba software, ranging from bridge file sharing, sharing device, PDC, firewall, DNS, DHCP, FTP, web server, a gateway, mail server, proxy and others. Facilities such as telnet and ssh pengremote also available. One other advantage is the application settings that are no longer based only text, but also graphics are based swat.
Wide Area Network
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Sharing of resources, for example the use of shared CPU, Hard Drive, Memory
Communication, for example Electronic mail, instant messaging, chat
Access to Information, for example Browsing
In order to achieve the same purpose, every piece of computer network request and provide the service (service). The party requesting the service are called clients (client) that provides services and called the waiter (server). This architecture is called client-server systems, and is used in almost all computer network applications.
Types of Computer Networks
1. Local Area Network (LAN)
Commonly abbreviated Local Area Network LAN is a computer network that covers only a small area networks, such as campus computer networks, buildings, offices, in homes, schools or smaller. Currently, most LANs based on the IEEE 802.3 Ethernet technology using a switch, which has a data transfer rate of 10, 100, or 1000 Mbit / s. In addition to Ethernet technology, the current 802.11b technology (or so-called Wi-Fi) is also often used to form a LAN. Places that provide LAN connectivity with Wi-Fi technology called hotspots.
On a LAN, each node or computer has the computing power of its own, different from the concept of a terminal dump. Each computer can access resources on the LAN in accordance with the permissions that have been set. These resources can be either data or a device such as a printer. On a LAN, a user can also communicate with other users using the application.
In contrast to Wide Area Networks or Wide Area Network (WAN), the LAN has the following characteristics:
1. Having rapidly to higher data
2. Covering a narrower geographical area
3. Does not require leased telecommunication lines from telecom operators
Usually one of the computers in the computer network server that will be used to manage all the systems in the network
2. Metropolitant Area Network (MAN)
Metropolitan area network or abbreviated as MAN is a network in a city with high speed data transfer, linking various locations such as campuses, offices, government and so on. MAN network is a combination of multiple LANs. The range of this MAN among 10 to 50 km, MAN is the right network to establish a network between offices in the city between factories / establishments and headquarters are within its range.
3. Wide Area Network
WAN stands for information technology term in English: Wide Area Network is a computer network covering a large area as an example of the computer networks between regions, cities or even countries, or can be defined as well as computer networks require routers and public communications channels.
WANs are used to connect a local network to another local network, so that the user or computer in one location can communicate with users and computers in other locations.
By function: Basically any existing computer network that serves as a client and server. But there is a network that has a dedicated computer as a server and the other as a client. There is also a computer that does not have a specific function as a server only. Because it is based on function then there are two types of computer networks:
a. Client-server
That is a computer network with a dedicated computer as a server. A service / service can be provided by a computer or more. An example is a domain such www.detik.com served by many of the web server computer. Or it could be a lot of service / services provided by a single computer. Examples are jtk.polban.ac.id server which is a computer with a multi service that mail server, web server, file server, database server and others.
b. Peer-to-peer
That is a computer network in which each host can be a server and a client simultaneously. For example, the file sharing between computers on the network Windows Network Neighbourhood there are 5 computers (we named A, B, C, D and E) are granted access to the files they have. At one point A to access the file share of B named data_nilai.xls and also gives access to the file soal_uas.doc C. When accessing a file from B then A serves as a client and as a give file access to C then A is acting as a server. Both functions were performed by the same A network like this so called peer to peer.
Based on the topology of the network: Based on [the network topology], computer networks can be distinguished:
1. Bus topology
2. Star Topology
3. Ring Topology
4. Topology Tree (Hierarchical)
5. Mesh Topology (Random)
Basic Components of Computer Network
To be able to build a network, there are some basic components that must be met, namely:
Physical Component
a. Computer Unit
Provide a minimum of 2 units of computer or multiple computers as needed, These computers later its acting as a server, and there is also a role as a workstation
b. Network Card or LAN Card (Network Interface Card)
In the visible LAN Card can easily be identified from its shape, which generally have port (jack) as terdapt on the phone, but a little bigger. This component is used onboard is already installed on some computers sold in the market today, if not mean you should add a way to plant the slot PCI / ISA section your computer mainboard ..
c. Cable Networks
wires in a network is used as a link. Although there is now a wireless network technologies (LAN) cable but still often used because it is easy to operate. There are several different types of cables are commonly used to build a network, among others:
c.1 Twisted Pair Cables
This cable consists of multiple wires wrapped around each other. The two types of cables that are included in this type of cable is Shielded Twisted Pair (STP) with a layer of aluminum foil and Unshielded Twisted Pair (UTP)
c.2 Coaxial Cable
Physical display cable consists of a copper wire core coated by an insulator and surrounded by the outer konduktur then covered with such materials as PVC outer insulator layer.
c.3 Fiber
Fiber optic cable consists of a glass fiber core and outer layers are wrapped like the cables are generally
d. Connectors
Connectors are used as a means of connecting the cable to plug LAN card that is in your computer CPU. Connector type is adjusted to the type of cable used as rj-45 paired with UTP / STP, BNC / T pairs with coaxial cable while type fiber optic ST connector is used.
e. Tang Kriping
Tang kriping Serves to clamp the cable with connectors already attached so it does not come off easily during installation. Using the pliers is adjusted by jebis cable you will use to build the network.
f. Hub
Hubs are network components that have plugs (ports). Generally hub has a port number ranging from 4, 8, 16, 24 to 32 plus 1 port (uplink) to connect to the server or to another hub. Hubs are used to unify network cables from each workstation, server or other device.
g. Bridge and Switch
Bridge used to connect separate networks and media liaison despite using models or different topologies. So similar to the bridge in our daily lives. While Switch looks like a hub, switch more clever difference being able to analyze the data that is passed to it before sending destination. In addition, he has the speed of data transfer from the server to the workstation or vice versa.
h. Router
Routers have the ability to filter or filter data passing across the network based on specific rules or protocol. Such as bridges, routers can also be used to connect multiple LAN and even WAN network model.
Non-Physical Component
In addition to the physical components that have been described previously, there are also non-physical component if we are going to learn to build a network, such as:
a. Operating Systems for Computers
There are many operating systems that you can use to build a computer network. For computer servers usually Microsoft Windows NT 4 Server, Microsoft Windows 2000 Server, Microsoft Windows 2003 Server, Novell Netware and Linux. As for the client / workstation you can use the Microsoft Windows 98, ME, 2000 Professional, XP and linux distro.
b. Network Protocols
Network protocols are the rules that are used in the network so that the computer-member computers and computer networks of different platforms can communicate with each other. TCP / IP (tranmission Control Protocol / Internet Protocol) is a protocol.
Wiring Techniques
As described in the previous chapter 3.3, there are several types of cables that can be used to build a computer network or in this case the LAN. But according to the authors by reason relatife easier procurement of cables, cheap and simple in the installation process as well as general use at this time, the choice fell on the type of cable types Unshielded Twisted Pair Twisted Pair (UTP).
UTP cable consists of 8 pieces of fine wires wrapped around each other into 4 pairs. The four pairs of cables are:
* Couples green cable with White Green lease
* Couple wiring color Orange with White lease Orange
* Blue color cable Couple lease with White Blue
* Cable Couple lease brown color with White Chocolate
Category UTP Cable
Cat 1: Used for communication devices, such as cable telephon.
Cat 2: Data transfer speeds up to 4 Megabits per second.
Cat 3: Usually used for token ring topology with data transfer speeds up to 10 Mbps.
Cat 4: Data transfer speeds reaching 16 Mbps
Cat 5: Data transfer speeds up to 100 Mbps
Cat 5e: Data transfer speeds up to 100 Mbps - 1 Gigabits.
Cat 6: The data transfer rate of up to 2.5 Gigabit Ethernet within 100 meters or 10 Gigabits within 25 Meters.
Standardization of UTP Cable
UTP Cabling Installation sequence generally follows the rules of the international standard EIA / TIA 568A and EIA / TIA 568B. To order EIA / TIA 568A wiring sequence is as follows:
Sequence to 1: White Green
Sequence 2: Green
Sequence 3: White Orange
Sequence 4: Blue
Sequence to 5: White Blue
Sequence 6: Orange
Rank 7: White Chocolate
Sequence to 8: Brown
While the order of EIA / TIA 568B cord sequence is as follows:
Sequence to 1: White Orange
Sequence 2: Orange
Sequence 3: White Green
Sequence 4: Blue
Sequence to 5: White Blue
Sequence 6: Green
Rank 7: White Chocolate
Sequence to 8: Brown
Cabling Type UTP
There are 2 types of UTP cabling connectors are RJ-45 type straight and cross type.
a. Type Straight
Straight type means that one end of the cable to the other end of the cable has the same wiring order in accordance with the standard EIA / TIA 568B. This type is used to connect the PC to the Switch, the Switch Router, Router to a PC to Hub and Hub.
b. Type of Cross
In this type of end of the cable using a standard sequence of EIA / TIA 568A and the other end of the cable it again using a sequence of TIS / EIA 568B and use to connect the PC to PC, Switch / Hub to Switch / Hub, and the PC to the router.
Jumat, 12 Oktober 2012
Server DNS
TCP / IP and IPv4 or IPv6
Dynamic Host Configuration Protocol (DHCP)
Domain Name System (DNS)
Active Directory (AD)
Routing and Remote Access
web Services
A DNS server is a computer that is running the DNS server program, such as the DNS server services or the Berkeley Internet Name Domain (BIND). DNS servers DNS database contains information about the parts of the tree structure of the domain DNS and name resolution requests are requested by the client DNS.
Server DNS was originally designed to locate hosts on the ARPANET and the Stanford Research Institute (SRI) maintains HOSTS.TXT file. if a computer is added to the network, the information from the computer is sent via email to the SRI.
Namespace hierarchy
Naming system which is based on her DNS server is a logical tree structure and hierarchy called the DNS namespace. At the root top-level domain in the central manage, while the second-level domains and the levels below it in managing the ownernya. DNS root servers to maintain data entry only top-level domain as a referral.
Domain in DNS server is part of the namespace that refers to all resources in an environment. While Zone in the DNS server can be explained as follows:
The portion in the namespace that contains the domain
One portion adjacent to the namespace in which the server is authoritative. DNS server can be authoritative for one or more zones, and a zone can consist of one or more adjacent domains.
Represented by a file stored on a DNS server. Zone files contain resource records for the zone in which the server is authoritative. In many implementations of DNS servers, the data is stored in a text file Zone: but; DNS server in the domain controller running Windows 2000 or Windows 2003 can also store files in the active directory information Zone.
Initially stores all information about a domain.
DNS resolver
A DNS resolver is a service that uses the DNS protocol to seek information from the DNS server. DNS resolver to communicate well with the DNS server or a remote control program that is on the local server computer. In Windows 2003, the functions of the DNS resolver DNS service performed by the client. Besides acting as the DNS resolver, the DNS Client service provides the additional functionality of the DNS cache mapping.
Resource record
Resource records are DNS database entries used to answer client questions. Server DNS contains resource records needed to answer questions about the portion of the DNS namespace.
Host address (A), which is the largest field of the resource record in a zone of the DNS server database that connects the computers (hosts) to their IP addresses.
Alias (CNAME) or also called canonical name, you can use it for more than one name to a single host.
Mail exchanger (MX) in a DNS server, use the email application to locate the e-mail server in a zone.
Pointer (PTR) in DNS server, use the reverse lookup zone which is the host name lookup based on IP address or FQDN (fully qualified domain name).
Service location (SRV) is used to specify the location of specific services within a domain.
Delegation
It was not possible to manage such large-scale namespace without a delegated administration Internet domain-2. Through a process of delegation, a new zone is formed when the responsibility of a sub-domain in the DNS namespace submitted to a separate entity. Separate entity can be autonomous organization or a branch of your business.
Delegates a sub-domain in a DNS server into a DNS record physic separating separate files.
When delegating Zone?
You should consider delegating a zone within your network when one or more of the following conditions appear:
You need a domain DNS delegation of management to a branch or department within your business organization.
You need to distribute the load of a DNS database maintenance immense into multiple name servers to improve the performance of a name resolution as well as fault tolerance.
And require structuring hosted by the branch naming your business or affiliate departments within your organization.
Type the DNS server
DNS server type refers to the type of zone in which the server hosting - or, in the case of Cache-only server (DNS sever that only serves as a cache) is not hosting him at all.
Primary name server
Save a copy of the zone file for the zone, the center of the zone update.
Changes or updates made to a zone created on the primary server.
With Windows 2003, you can deploy a standard primary zone as a primary zone or the primary zone is integrated with Active Directory.
Secondary name servers - a recommendation in the design specifications, to provide offload DNS query traffic in an area that has a load demand and use are very large.
As a backup copy of the zone file if the primary server is down
Kept separate in physics
Make Pointer to the primary name server and periodically perform zone transfers.
Caching name-server
Not hosting any zone
Not authoritative for a zone anywhere
As a cache lookup only, limited to what he cache when he resolves the request of clients.
DNS requests and stores the result
In an environment Berkeley Internet Name Domain (BIND), primary name server is often referred to as a master name server as secondary server in refernsi nae as a slave name server in an enterprise computer network.
LAN and WAN
Ethernet defines both Layer 1 (Physical Layer) and layer2 (Data Link Layer) of the OSI reference model. Phyisical layer and data link layer works together to provide the function of sending data through various types of physical networks. Some details of the physical function must be met before any communication takes place, such as cable networks, type-2 connectors are used at the ends of two wires, and so is the level of voltage and current used to encode binary 0 and 1.
Data Link layer protocols define or rule-2-2 to determine when a computer may use the physical network when the computer is not supposed to use the network, and how to find the errors that occur during transmission of data.
The term Ethernet refers to the family of protocols and standards that together-2 defines physical layer and data link from the most popular type of LAN. There are many variants of Ethernet include:
1. 10 Base-T
2. Fast Ethernet
3. Gigabit Ethernet
10Base-T Ethernet network
10-BaseT Ethernet network allows us to use existing telephone wiring, or a cheaper cable if needed a new cable. 10-BaseT Ethernet network using what is called a HUB devices. Physical network using Ethernet 10-BaseT Ethernet Card or NIC (Network Interface Card) on the computer, cabling and a hub (which is one of the most ancient network devices).
HUB used in 10-BaseT Ethernet network is basically a multiport repeater. This means that the HUB is only 2 devices amplifier electrical signal that goes to one of the ports and distributed to all ports of the HUB, so crash (collision) is very possible.
Network cabling Ethernet 10Base-T
10-BaseT Ethernet network using Category 5 UTP cable with RJ-45 connectors.
The cable used to connect computers to the HUB using Straight-through cables
The cable connects between the HUB using a cross cable.
In some kind of hub or switch now been using autosensing - which identify the type of cable you are, so do not have to use a cable cross - just use a straight through cable for all connections.
Collision be a performance problem HUB
Network Ethernet 10-Base2; 10Base5, and 10BaseT not be able to walk without the CSMA / CD. However, the algorithm CSMA / CD, Ethernet becomes less efficient at higher loads, Ethernet will be a slow start when network load exceeds 30% usage.
How CSMA / CD logic helps keep the collision (collision) as well as how he reacts when a collision occurs. Like the highway in both directions, as well as what happens on the network vulnerable HUB collision. The algorithm CSMA / CD can be explained as follows:
1. A network device with a frame of data to be sent, first to listen to the network whether it is quiet or not.
2. If the Ethernet network is no longer busy, the sender begins sending data frames to the network.
3. The sender look to determine whether a collision or not.
4. As soon as the sender knows the event of a collision, they each send a signal jamming-2 (signal path congestion) to ensure that all stations know that a collision has occurred.
5. As soon as the jamming signal is sent, the sender calculates every (timer) randomly and wait for it anyway before they start sending the frame to the network.
6. If the timer is up, then the process starts again from the beginning steppertama, and so on up to successfully send a data frame to the fixed address.
LAN Swith - reducing collisions
Collision term defines a set of device domains within a boundary that allows a data frame collisions occur. All devices on a network 10Base2, 10Base5, and 10Base-T HUB menggunkaan risk collisions between frames that they send, so all devices that exist on any type of Ethernet networks are in one collision domain.
For that emerged LAN Switch that can overcome this problem domain collisions and also problems algorithm CSMA / CD to relieve the possibility of collision. Unlike HUB, Switch does not create a shared bus, Switch treats each port as a separate bus. Switches use a memory buffer to hold data frames are coming, so if there are two devices on Switch tergubung simultaneously transmit data, the switch sends the frame and holds the second frame into a memory buffer, then wait to send the second frame to the first frame was finished being sent so it will never happen collisions.
Full-Duplex - eliminating collisions
Original specification of Ethernet is using a shared bus, while at the same time there is only one frame that could be sent or lajim called Half-Duplex. LAN switches with only one device connected to each port on the switch allows operation Full-Duplex. Full-duplex means that an Ethernet card can send and receive frames simultaneously.
Conclusion Ethernet Network
Protocol-2 physical layer defines how to transmit data across the physical medium. Protocol-2 data link layer is useful to make the physical network by defining how and when the physical network is used. Defining an Ethernet network layer of the OSI model serves first for Ethernet networks, including cabling, connectors, voltage level, and the cable distance limits, as well as many important functions of Layer 2 of the OSI model.
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