|
|
|
|
| Use the links below to learn more about our services. | |
|
|
| General Information | |
|
Service Levels |
|
Co-Location |
|
Virtual Domains |
|
Use Policy |
|
Common Questions |
|
|
| Support Options | |
|
Technical Support |
|
Emergency Support |
|
|
| Pricing | |
|
Co-Location Pricing |
|
Virtual Pricing |
|
|
| Sales and Contact | |
|
Online Ordering |
|
Contact Us |
|
|
| Strategic Partners | |
|
Front End |
|
Back End |
|
Hardware |
|
|
| Site Navigation | |
|
Site Index |
|
Return Home |
|
|
What is TCP/IP, Packets, and Routers
The Internet is a collection of networks that presently use the TCP/IP protocol suite and operate as one cooperative, virtual network. It has recently grown rapidly across much of the world and is presently found in almost every country.
For the purpose of this example, let's assume that you want to send a file to a friend who lives on the opposite side of the country. You select the file that your friend wants and you send it. Transmission Control Protocol / Internet Protocol (TCP/IP) prepares the data to be sent and received. TCP/IP ensures that a Macintosh network can exchange data with a Windows, or a Unix network, and vice-versa. The file that you are sending does not travel to your friend's computer directly, or even in a single continuous stream. The file you are sending gets broken up into separate data packets. The Internet Protocol side of TCP/IP labels each packet with the unique Internet address, or IP address of your friend's computer. Since these packets will travel separate routes, some arriving sooner than others, the Transmission Control Protocol side of TCP/IP assigns a sequence number to each of packets. These sequence numbers will tell the TCP/IP in your friend's computer how to reassemble the packets once he receives them. Amazingly, the complicated process of TCP/IP takes place in a matter of milliseconds.
The packets travel from one "router" to the next. Each router reads the destination IP address of the packet and decides which path will be the fastest. Since the traffic on these paths is constantly changing, each packet may be sent a different way. Each point on the internet that the router uses to send data (step by step in a connect-the-dots fashion) has a variable amount of traffic and variable connection speed, limited primarily by the hardware in place and the sheer volume of packets traveling through that particular location. Once these packets arrive at the destination, they are then reassembled in the proper sequence to allow the file to arrive in its original form. This happens every time you visit an internet web page: data is transferred to your system via TCP/IP, with varying degrees of performance.
What are IP's, Domain Names, and Name Servers
Every single location (machine, router, name server, hosting account, etc.) on the Internet has at least one unique IP address, which is most commonly represented as four numbers joined by periods (.), like 199.227.124.197. These function just like street addresses for the internet. There are literally thousands of different possible IP addresses. These addresses represent the exact location of a particular site on the internet, and serve to guide any other user to that location. Each location on the internet might also have one or more domain names that refer to the IP address.
For example, the domain name terahost.net refers to our location on the internet, which is currently 209.125.112.5. Since it would be impossible for anyone to remember which domain names were matched up to each IP address, the internet has large computers, called name servers, that serve as translators. These name servers can look up any domain name and resolve it into the IP address to which it refers. Whenever a user refers to terahost.net, or any other domain name, that information is sent to a name server (normally at the Internet Service Provider of the user), and the name server returns the matching IP address so that the site can be visited. All of this happens behind the scenes.
IP addresses and domain names aren't assigned arbitrarily - that would lead to unbelievable confusion. An application must be filed with the InterNIC for each domain name needed, and each domain name must have a matching IP address somewhere on the internet.
Are there useful Internet utilities
Windows/DOS and UNIX users:
There are a few useful tools that you can access from the command (or DOS) prompt that allow you to determine if there is an Internet problem. Note that you must be connected to an ISP to use these:
Traceroute:
From a command prompt on a computer with an active connection to the Internet, type "tracert www.domain.com" to trace the route over the internet to a particular domain. Hops with long lag will show up easily here.
Ping:
Again from the prompt, type "ping www.domain.com" to determine the time in milliseconds for a packet to reach the destination and back. This is useful to determine the speed of access to a particular area.
Whois:
You can visit InterNIC's Web Interface to WHOIS to check the InterNIC database also.
© 1998 - 1999 TeraHost Internet Services. All rights reserved.