jarkom: Januari 2009

Minggu, 04 Januari 2009

DNS

DNS (Domain Name System)
• "Distribute Database System" that is used to search the computer name (name resolution) in the network that use the TCP / IP

• DNS is an application services used in the web browser such as Internet or e-mail that translates a domain name to IP address.

Why do we need DNS?
When the client computer search for other computers (X) dijaringan different & do not know how the number of IP Address, the computer need the help of computer Client DNS server to know how the IP Address X-based computer domain names that we submit to the DNS server computer.

How to Work DNS

• map the DNS name into the computer IP address
• DNS Client called resolvers and DNS server is called with the name servers.

The principle of DNS

1. Resolvers (client) to send queries to the server name
2. check name server to a local database, or contact the other server name, if found to be notified if resolvers will not send a message failure
3. Resolvers to host the dituju using the IP address given name server

Excellence DNS
• Easy, DNS is easy because the user no longer direpotkan to remember the IP address a computer, simply name the host name (Computer).
• Consistent, a computer IP address may be changed, but the host name should not be changed.
• Simple, user only uses one name for the domain name in both the Internet and the Intranet, although there are many mirror server is used.

Domain structure. ID

• Domain must be under the second-level domain
•. Ac: academic (education)
•. Co: company (company)
•. Or: organization, others
•. Net: network (for ISP)
•. Go: government (the government)
•. Mil: military
•. SCH: school
•. Web: web
• Special:
•. War.net.id: warnet

Structure of DNS

Domain Name System is a hierarchical grouping based on the domain name, which is divided into several sections including:
• Root Domain
• Top Level Domains (Generic and Country)
• Second Level Domains
• fqdn (Third Level Domains)
• Host Names

Jumat, 02 Januari 2009

ROUTER

Router tool is a computer network that sends packets of data through a network or the Internet to its destination, through a process known as routing

Router function:
LAN network connects to the Internet in merutekan tranmisi between the two. ROUTER menstranmisikan information from one network to another network system that works similar to BRIDGE.

In general, the router is divided into two types, namely:

* Static router (the router static) is a router that has a static routing table is set manually by the network administrator.
* Wasted the router (the router dynamic) is a router that has a dab create dynamic routing table, listening to the traffic network with each other and also connected with other routers.

The difference between static and dinamic:

Static routing is configured manually. Routing table is set manually and stored in the router. No information sharing among the router. This resulted in the clear limitations because he can not automatically determine the best route; he always use the same routes that are likely not the best route. If the route change, static router must be updated manually. Because the static router provides full control on the routing table, it is more secure than the dynamic router.

Dynamic routing is able to create their own routing table to talk with fellow router. To do so, he found an alternative route and the route that are on the network. Dynamic router can make a decision on which route a packet reaches the destination. Generally, he sends the package to the most efficient route; the one that produces fewer number of hop. However, if the jammed route, dynamic route can send packages to the alternative route.