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Using CIDR, each IP address has a network prefix that identifies either an aggregation of network gateways or an individual gateway. The length of the network prefix is also specified as part of the IP address and varies depending on the number of bits that are needed (rather than any arbitrary class assignment structure). A destination IP address or route that describes many possible destinations has a shorter prefix and is said to be less specific. A longer prefix describes a destination gateway more specifically. Routers are required to use the most specific or longest network prefix in the routing table when forwarding packets.
A CIDR network address looks like this:
192.30.250.00/18
The "192.30.250.00" is the network address itself and the "18" says that the first 18 bits
are the network part of the address, leaving the last 14 bits for specific host addresses.
CIDR lets one routing table entry represent an aggregation of networks that exist in the
forward path that don't need to be specified on that particular gateway, much as the public
telephone system uses area codes to channel calls toward a certain part of the network.
This aggregation of networks in a single address is sometimes referred to as a supernet.
CIDR is supported by The Border Gateway Protocol, the prevailing exterior (interdomain)
gateway protocol. (The older exterior or interdomain gateway protocols, Exterior Gateway
Protocol and Routing Information Protocol, do not support CIDR.) CIDR is also supported by
the OSPF interior or intradomain gateway protocol.
Clearance
DHCP supports static addresses for computers containing Web servers that need a permanent
IP address.
DHCP is an alternative to another network IP management protocol,
Bootstrap Protocol (BOOTP). DHCP is a more advanced protocol, but both configuration
management protocols are commonly used. Some organizations use both protocols, but
understanding how and when to use them in the same organization is important. Some
operating systems, including Windows NT/2000, come with DHCP servers. A DHCP or BOOTP
client is a program that is located in (and perhaps downloaded to) each computer so that it
can be configured.
FreeType is a font service and doesn't provide APIs to perform higher-level features, like text layout or graphics processing
(e.g., colored text rendering, "hollowing", etc.). However, it greatly simplifies these tasks by providing a simple, easy to
use and uniform interface to access the content of font files.
GD can create images composed of lines, arcs, text (using program-selected fonts), other images, and multiple colors. Version
2.0 adds support for truecolor images, alpha channels, resampling (for smooth resizing of truecolor images), and many other
features.
GD supports numerous programming languages including C, PHP, Perl, O'Caml, Tcl, Lua, Pascal, GNU Octave and REXX. There is
also a tool called fly which allows access to GD from any language through a command-line program.
GD is extensively used with PHP, where a modified version supporting additional features is included by default as of PHP 4.3
and was an option before that.
The Internet Protocol (IP) is the method or protocol by which data is sent from one
computer to another on the Internet. Each computer (known as a host) on the Internet has at
least one IP address that uniquely identifies it from all other computers on the Internet.
When you send or receive data (for example, an e-mail note or a Web page), the message gets
divided into little chunks called packets. Each of these packets contains both the sender's
Internet address and the receiver's address. Any packet is sent first to a gateway computer
that understands a small part of the Internet. The gateway computer reads the destination
address and forwards the packet to an adjacent gateway that in turn reads the destination
address and so forth across the Internet until one gateway recognizes the packet as
belonging to a computer within its immediate neighborhood or domain. That gateway then
forwards the packet directly to the computer whose address is specified. Because a message
is divided into a number of packets, each packet can, if necessary, be sent by a different
route across the Internet. Packets can arrive in a different order than the order they were
sent in. The Internet Protocol just delivers them. It's up to another protocol, the
Transmission Control Protocol (TCP) to put them back in the right order.
IP is a connectionless protocol, which means that there is no continuing connection between
the end points that are communicating. Each packet that travels through the Internet is
treated as an independent unit of data without any relation to any other unit of data. (The
reason the packets do get put in the right order is because of TCP, the connection-oriented
protocol that keeps track of the packet sequence in a message.) In the Open Systems
Interconnection (OSI) communication model, IP is in layer 3, the Networking Layer.
The most widely used version of IP today is Internet Protocol Version 4 (IPv4). However, IP
Version 6 (IPv6) is also beginning to be supported. IPv6 provides for much longer addresses
and therefore for the possibility of many more Internet users. IPv6 includes the
capabilities of IPv4 and any server that can support IPv6 packets can also support IPv4
packets.
This definition is based on Internet Protocol Version 4. Note that the
system of IP address classes described here, while forming the basis for IP address
assignment, is generally bypassed today by use of Classless Inter-Domain Routing (CIDR) addressing.
In the most widely installed level of the Internet Protocol ( IP) today,
an IP address is a 32-bit number that identifies each sender or receiver of information
that is sent in packets across the Internet. When you request an
HTML page or send e-mail, the Internet Protocol part of TCP/IP
includes your IP address in the message (actually, in each of the packets if more than one
is required) and sends it to the IP address that is obtained by looking up the domain name in the Uniform Resource Locator you
requested or in the e-mail address you're sending a note to. At the other end, the
recipient can see the IP address of the Web page requestor or the e-mail sender and can
respond by sending another message using the IP address it received.
An IP address has two parts: the identifier of a particular network on the Internet and an
identifier of the particular device (which can be a server or a workstation) within that
network. On the Internet itself - that is, between the
router that move packets from one point to another along the route - only
the network part of the address is looked at.
The Internet is really the interconnection of many individual networks (it's sometimes
referred to as an internetwork). So the Internet Protocol (
IP) is basically the set of rules for one network communicating with any
other (or occasionally, for broadcast messages, all other networks). Each network must
know its own address on the Internet and that of any other networks with which it
communicates. To be part of the Internet, an organization needs an Internet network
number, which it can request from the Network Information Center (NIC). This unique
network number is included in any packet sent out of the network onto the Internet.
Part of the local address can identify a subnetwork or
subnet address, which makes it easier for a network that is divided into
several physical subnetworks (for examples, several different local area networks or
The first few bits of each IP address indicate which of the address class formats it is using. The address structures look like this:
Class A
Class B
Class C
Class D
The IP address is usually expressed as four decimal numbers, each representing eight bits,
separated by periods. This is sometimes known as the dot address and, more technically, as
dotted quad notation. For Class A IP addresses, the numbers would represent
"network.local.local.local"; for a Class C IP address, they would represent
"network.network.network.local". The number version of the IP address can (and usually is)
represented by a name or series of names called the
domain name.
The Internet's explosive growth makes it likely that, without some new architecture, the
number of possible network addresses using the scheme above would soon be used up (at
least, for Class C network addresses). However, a new IP version, IPv6, expands the size
of the IP address to 128 bits, which will accommodate a large growth in the number of
network addresses. For hosts still using IPv4, the use of subnets
in the host or local part of the IP address will help reduce new applications for network
numbers. In addition, most sites on today's mostly IPv4 Internet have gotten around the
Class C network address limitation by using the Classless Inter-Domain Routing ( CIDR) scheme for address notation.
The discussion above assumes that IP addresses are assigned on a static basis. In fact,
many IP addresses are assigned dynamically from a pool. Many corporate networks and online
services economize on the number of IP addresses they use by sharing a pool of IP addresses
among a large number of users.
"Packet" and "datagram" are similar in meaning. A protocol similar to TCP, the User
Datagram Protocol(UDP) uses the term datagram.
Transmission Control Protocol (TCP), which uses a set of rules to exchange messages with
other Internet points at the information packet level. Internet Protocol (IP), which uses
a set of rules to send and receive messages at the Internet address level. Additional
protocols that are usually packaged with a TCP/IP suite, including the Hypertext Transfer
Protocol (HTTP) and File Transfer Protocol (FTP), each with defined sets of rules to use
with corresponding programs elsewhere on the Internet.
A router may create or maintain a table of the available routes and their conditions and
use this information along with distance and cost algorithms to determine the best route
for a given packet. Typically, a packet may travel through a number of network points with
routers before arriving at its destination. Routing is a function associated with the
Network layer (layer 3) in the standard model of network programming, the Open Systems
Interconnection (OSI) model. A layer-3 switch is a switch that can perform routing
functions.
An edge router is a router that interfaces with an asynchronous transfer mode (ATM)
network. A brouter is a network bridge combined with a router.
It would be simple if every computer that connects to the Internet could have its own
static IP number, but when the Internet was first conceived, the architects didn't foresee
the need for an unlimited number of IP addresses. Consequently, there are not enough IP
numbers to go around. To get around that problem, many Internet service providers limit the
number of static IP addresses they allocate, and economize on the remaining number of IP
addresses they possess by temporarily assigning an IP address to a requesting Dynamic Host
Configuration Protocol (DHCP) computer from a pool of IP addresses.
The temporary IP address is called a dynamic IP address.
Requesting DHCP computers receive a dynamic IP address (think temporary phone number) for
the duration of that Internet session or for some other specified amount of time. Once the
user disconnects from the Internet, their dynamic IP address goes back into the IP address
pool so it can be assigned to another user. Even if the user reconnects immediately, odds
are they will not be assigned the same IP address from the pool. To keep our telephone
telephone analogy going, using a dynamic IP address is similar to using a pay phone. Unless
there is a reason to receive a call, the user does not care what number he or she is
calling from.
There are times, however, when users who connect to the Internet using dynamic IP wish to
allow other computers to locate them. Perhaps they want to connect to an office intranet or
use an application that requires a known IP address. In that case, they would need a static
IP address. The user has two choices; they can request a static IP address, or they can use
a dynamic DNS service. Obtaining a static IP address involves an additional monthly fee.
Using a dynamic DNS service works as if there was an old-fashioned telephone message
service at your computer's disposal. When a user registers with a DNS service and connects
to the Internet with a dynamic IP address, the user's computer contacts the DNS service and
lets them know what IP address it has been assigned from the pool; the service works with
the DNS server to forward the correct address to the requesting DHCP computer. (Think of
calling the message service and saying "Hi. I can be reached at 435.44.32.111 right now.
Please tell anyone who tries to reach me to call that number.) Using a dynamic DNS service
to arrange for computers to find you even though you are using a dynamic IP address is the
next-best thing to having a static IP.
Relative to the layered Open Systems Interconnection (OSI) communication model, a switch is
usually associated with layer 2, the Data-Link layer. However, some newer switches also
perform the routing functions of layer 3, the Network layer. Layer 3 switches are also
sometimes called IP switches.
On larger networks, the trip from one switch point to another in the network is called a
hop. The time a switch takes to figure out where to forward a data unit is called its
latency. The price paid for having the flexibility that switches provide in a network is
this latency. Switches are found at the backbone and gateway levels of a network where one
network connects with another and at the subnetwork level where data is being forwarded
close to its destination or origin. The former are often known as core switches and the
latter as desktop switches.
In the simplest networks, a switch is not required for messages that are sent and received
within the network. For example, a local area network may be organized in a token ring or
bus arrangement in which each possible destination inspects each message and reads any
message with its address.
Circuit-Switching version Packet-Switching
Disk Space:
Disk space is the storage capacity of your website (for pictures, HTML,
graphics, etc.). Web Presence Pack comes with 20MB, while E-Commerce
Builder sites can store 50MB of data.
Domain Name:
A registered name that is given to an Internet IP address so that the
address is easy to remember. For example, imbris.com
Domain Registration:
Domain Name Registration is the process of registering your website
address (i.e. www.imbris.com) with the InterNIC, the official Internet
registry. This service is provided free of charge to all IMBRIS, Inc.
customers; however, there is a small fee paid directly to
the registrar. This process is usually quick because of IMBRIS, Inc.'s
status as an Internic Premier Partner. In order to sign-up for any hosting
account, you must have a registered domain name.
Download:
The act of retrieving a file from the Internet or a server.
Downstream:
This term refers to the path of data from the Internet to your computer,
such as when you are surfing the web or downloading a file.
E-Commerce Builder:
For companies that want to sell goods and services through their website,
E-Commerce Builder is the ideal solution. E-Commerce Builder can be used
to publish simple online catalogs or to create robust, e-commerce sites
where customers can purchase -- and pay for -- their goods online.
E-mail:
Electronic Mail - Messages transmitted over the Internet from user
to user. E-mail can contain text, but also can carry with it files of any
type as attachments.
E-mail Autoresponders:
Autoresponders allow you to automatically send out standardized e-mails
when any of your mailboxes receives a message.
E-mail Forwarding:
When you first set up your hosting account, all e-mails will be sent to
your "default" address (i.e. admin@yourcompany.com). If you wish, you can
change the name on your e-mail addresses and the mail will automatically
be forwarded.
E-Mail Mailboxes:
There are two fundamental components of e-mail: 1) the address
itself; and 2) the mailbox into which messages are deposited. IMBRIS,
Inc. hosting accounts include mailboxes which you can assign to staff or
family members, or use to separate your mail into logical departments
(sales, support, etc.). If you or your staff already have mailboxes at
work, or with an ISP, you don't have to reconfigure your mail
client. Let's assume your domain name is www.bobstowing.com, and you
already have a mailbox on IMBRIS named bob12. We can configure your
account so that sales@bobstowing.com forwards to bob12@imbris.net. This
way, you will receive all of your e-mail in one place.
Ethernet:
Ethernet is the most widely-installed local area network (LAN) technology.
Specified in a standard, IEEE 802.3, Ethernet was originally developed by Xerox and then
developed further by Xerox, DEC, and Intel. An Ethernet LAN typically uses coaxial cable or
special grades of twisted pair wires. The most commonly installed Ethernet systems are
called 10BASE-T and provide transmission speeds up to 10 Mbps. Devices are connected to the
cable and compete for access using a Carrier Sense Multiple Access with Collision Detection
(CSMA/CD) protocol. Fast Ethernet or 100BASE-T provides transmission speeds up to 100
megabits per second and is typically used for LAN backbone systems, supporting workstations
with 10BASE-T cards. Gigabit Ethernet provides an even higher level of backbone support at
1000 megabits per second (1 gigabit or 1 billion bits per second).
FAQ:
Frequently Asked Questions - Files that are maintained at Internet
sites to answer frequently asked questions so that new users can more
quickly get oriented to the system. It is good netiquette to read
the FAQ and poor netiquette to ask questions that are
answered in a FAQ.
Favorites:
A feature of Microsoft Internet Explorer that stores the URL of Web
pages for quick access. When you save a Web address in your
Favorites, you can give it any name you choose and then return to
it by clicking on that name.
Flames:
Insulting, enraged Internet messages. The equivalent of schoolyard brawls
in cyberspace. Found on occassion in newsgroups and mailing lists.
FreeType Library:
A software library that implements a font engine. It is used to rasterize characters into bitmaps and provides support for
other font-related operations.
FTP:
File Transfer Protocol - The basic Internet function that enables
files to be transferred between computers. You can use it to download
files from a remote host computer, as well as to upload files from your
computer to the Imbris servers.
Anonymous FTP - Using FTP without a username and password for
access. Use the word anonymous as the login and your complete
e-mail address as the password. Anonymous FTP is often permitted on large
computer systems that share some of their files.
Gateway:
A gateway is a network point that acts as an entrance to another network. On
the Internet, a node or stopping point can be either a gateway node or a host (end-point)
node. Both the computers of Internet users and the computers that serve pages to users are
host nodes. The computers that control traffic within your company's network or at your
local Internet service provider (ISP) are gateway nodes. In the network for an enterprise,
a computer server acting as a gateway node is often also acting as a proxy server and a
firewall server. A gateway is often associated with both a router, which knows where to
direct a given packet of data that arrives at the gateway, and a switch, which furnishes
the actual path in and out of the gateway for a given packet.
GD Graphics Library:
GD Graphics Library - is a library by Thomas Boutell and others for dynamically manipulating images.
It can create GIFs, JPEGs, PNGs, and WBMPs.
GIF:
Graphics Interchange Format - A graphics file format that is
commonly used on the Internet to provide graphic images and pictures in
Web pages.
Graphical Statistics:
Through pwebstats, clients can access graphical reports showing site
usage statistics.
gTLD:
Generic Top Level Domain - Most often referred to as "Web
Extensions" and presently include .com, .net, .org
domains. Coming soon to gTLDs are .biz. and .info.
HTML:
Hyper Text Markup Language - Basic language that is used to create
documents on the web, it is the standard language allowing web browsers to interpret
websites. HTML documents are interpreted by Web browsers to display
text, set colors, select fonts, add graphic images, play sound or video
clips, and to link Web pages to other Internet Web sites.
Hosting:
During the first few years of the World Wide Web, the only way to obtain
a fully functional corporate presence on the Internet was to set
everything up "in house". That meant purchasing a web server, getting a
leased line installed (T1 or higher), hiring a full-time system
administrator (or webmaster), obtaining adequate emergency power (UPS or
generator), and so on. This level of investment made the Internet too
expensive for many small to medium-sized business. Even for larger
corporations, the investment required to maintain a website diverted
significant resources from their core business' focus. Fortunately, a
solution has been developed that enables businesses to obtain a higher
level of service than they could ever afford to achieve internally, while
virtually eliminating the cost of entry: web hosting. Advancements in
technology have enabled businesses to outsource some or all of the aspects
of their Internet operation to external services. Hosting services can
setup and maintain more than just websites; they can also support a
company's e-mail, databases, and even end-to-end payment processing
systems. By outsourcing these applications, businesses get all of the
benefits of the provider's high-speed backbone connection, 24/7 operations
personnel, facilities, and emergency power without the enormous capital
investment. As the industry matures, hosting services have begun to expand
beyond Internet applications to more complete MIS solutions, enabling
businesses to focus more resources on enhancing their products and
services, and less on maintaining information systems.
Hypertext:
Documents that contain links to other documents. You can click on a
hypertext link to jump to the documents specified by the link's Uniform
Resource Locator (URL) or Uniform Resource Identifier
(URI). Using URLs and URIs, you can link to any Web
document in the world.
InterNIC:
The official domain name registry of the Internet.
InterNIC Confirmation
E-mail:
NetworkSolutions will send you an invoice via e-mail 1 to 6 weeks after
your domain name is registered. Let us know if you do not receive notification
that a domain name has been either registered or transferred within two
weeks. In the meantime, refer all concerns to Registration Services. You
can reach them by calling (703) 742-4777, or
you may e-mail them at hostmaster@networksolutions.com. Be sure to
reference your NIC ticket number when contacting either IMBRIS, Inc. or the
InterNIC.
InterNIC Fees:
The InterNIC charges $70 to register a new domain name (.com, .net,
.org). This fee covers the first two years. They currently bill at a rate
of $35 per year.
InterNIC Setup:
IMBRIS, Inc. can expedite the registration of your domain and make sure
everything goes smoothly. We will send your domain registration or
transfer request to the InterNIC on your behalf.
IP:
Internet Protocol - Simple description - "The number that identifies your machine as unique on the Internet".
Technical description - The format of data packets (envelopes for your
data) that are exchanged on the Internet. (Also see TCP/IP.)
IP Address:
An Internet address. A number consisting of 4 parts separated by dots,
sometimes called a dotted quad." For example, 198.204.112.1. Every
Internet computer has an IP address. Most computers also are assigned one
or more Domain Names that are easier to remember than the dotted quad.
The Network Part of the IP Address
The Local or Host Part of the IP Address
In addition to the network address or number, information is needed about which specific
machine or host in a network is sending or receiving a message. So the IP address needs
both the unique network number and a host number (which is unique within the network). (The
host number is sometimes called a local or machine address.)
IP Address Classes and Their Formats
Since networks vary in size, there are four different address formats or classes to consider when applying to NIC for a network number:
0 Network (7 bits) Local address (24 bits)
10 Network (14 bits) Local address (16 bits)
110 Network (21 bits) Local address (8 bits)
1110 Multicast address (28 bits) Relationship of the IP Address to the Physical Address
The machine or physical address used within an organization's local area networks may be
different than the Internet's IP address. The most typical example is the 48-bit Ethernet address. TCP/IP includes a facility called the Address
Resolution Protocol ( ARP) that lets the administrator create a table
that maps IP addresses to physical addresses. The table is known as the ARP cache.
Static versus Dynamic IP Addresses
IRC:
Internet Relay Chat - An Internet tool that lets users join a
"chat" channel and exchange messages. IRC is soon going to permit the
full-color, live-action video required for video-conferencing.
ISP:
Internet Service Provider - A company that provides a gateway to
the Internet through a variety of means, including dial-up access, DSL,
ISDN, Frame Relay and Wireless.
JAVA:
A programming language that permits Internet sites on the World
Wide Web to run computer applications such as games, animation effects,
database searches and many other functions.
JavaScript:
A simplified subset of Java that enables Web authors to use
Java without needing to know how to program in the full Java language.
JPEG:
Joint Photographic Experts Group - An Internet graphic image com-
pression standard that is optimized for full-color or gray-scale
photographic- type, digital images. It doesn't work well on drawn images
such as line draw- ings, and it does not handle black-and-white images or
video images.
Mailing List:
An e-mail-based discussion group. Sending one message to the mailing
list's server sends mail to all other members of the group. Users join a
mailing list by subscribing. Subscribers to a mailing list receive
messages from all other members. Users have to unsubscribe from a mailing
list to stop receiving messages forwarded from the group's members.
MIME:
Multipurpose Internet Mail Extensions - An Internet standard that
lets computer files be attached to e-mail. Files sent by MIME arrive as
exact copies of the original so that you can send word processing files,
spreadsheets, graphics images and software applications to other users,
provided the recip- ient has a MIME-capable e-mail application—most e-mail
programs today are MIME-capable, including the one we've given you.
Modem:
An electronic device that lets computers communicate using regu-
lar phone lines or cable TV systems. The name is derived from the true,
technical name: modulator-demodulator.
Multi-processor Unix
Servers:
IMBRIS, Inc. servers run the Unix operating system for maximum
performance and reliability. No knowledge of Unix is required to use your
hosting account. IMBRIS, Inc.'s experienced system administrators will
handle the installation, configuration and maintenance of the Unix
servers.
Netiquette:
Internet etiquette. Good netiquette will keep you out of
trouble in newsgroups and mailing lists.
Newsgroup:
An electronic, community bulletin board that enables Internet users all
over the world to post and read messages that are public to other users of
the group. There are more than 25,000 public newsgroups and thousands of
private newsgroups collecting tens of gigabytes of data daily. No one
knows the actual count of current newsgroups because it changes so rapidly
as new ones are added and older ones are dropped.
NIC:
Network Interface Card - An adapter card placed into your
computer to allow it to communicate with other networkable devices, such as
an external cable modem.
NNRP:
Network News Transfer Protocol - An Internet protocol that handles
the transfer of Usenet newsgroups between Usenet news servers.
NTP:
Network Time Protocol - An Internet standard protocol (built on top of TCP/IP) that assures accurate synchronization to the millisecond of
computer clock times in a network of computers. Based on UTC, NTP synchronizes client workstation clocks to the U.S.
Naval Observatory Master Clocks in Washington, DC and Colorado Springs CO. Running as a continuous background client
program on a computer, NTP sends periodic time requests to servers, obtaining server time stamps and using them to
adjust the client's clock.
Packet:
A packet is the unit of data that is routed between an origin and a destination on the
Internet or any other packet-switched network. When any file (e-mail message, HTML file,
Graphics Interchange Format file, Uniform Resource Locator request, and so forth) is sent
from one place to another on the Internet, the Transmission Control Protocol (TCP) layer of
TCP/IP divides the file into "chunks" of an efficient size for routing. Each of these
packets is separately numbered and includes the Internet address of the destination. The
individual packets for a given file may travel different routes through the Internet. When
they have all arrived, they are reassembled into the original file (by the TCP layer at the
receiving end). A packet-switching scheme is an efficient way to handle transmissions on a
connectionless network such as the Internet. An alternative scheme, circuit-switched, is
used for networks allocated for voice connections. In circuit-switching, lines in the
network are shared among many users as with packet-switching, but each connection requires
the dedication of a particular path for the duration of the connection.
Peering:
Ever wonder how data gets from one network (MCI) to another (AT&T) on the
Internet? It's not as simple as you might think. Most major Internet
companies will not exchange data with you until you establish a peering
agreement. The more peering agreements you have, the faster your data will
get to end users. For instance, if you peer with AOL, requests for web
pages from your servers will go directly to their network. If you don't
peer with AOL, your data may have to traverse several networks before it
reaches one that peers with their network. Having a direct connection to
the Internet hubs is not very useful unless the other companies connected
to the facility will exchange data with you. IMBRIS, Inc. has peering
agreements with dozens of major networks.
PHP:
PHP Hypertext Preprocessor - A scripting language used to create dynamic Web pages. With syntax from
C, Java and Perl, PHP code is embedded within HTML pages for server side execution. It is commonly used to
extract data out of a database and present it on the Web page. NT/2000 and Unix Web servers support the
language, and it is widely used with the mSQL database. PHP was originally known as "Personal Home Page."
POP:
Point-of-Presence - A location that offers Internet access, usually
through an ISP. POPs are located in areas
covered by Internet Service Providers to afford customers a local (no long distance) access
telephone number.
Protocol:
In information technology, a protocol (pronounced PROH-tuh-cahl, from the Greek
protocollon, which was a leaf of paper glued to a manuscript volume, describing its
contents) is the special set of rules that end points in a telecommunication connection use
when they communicate. Protocols exist at several levels in a telecommunication connection.
There are hardware telephone protocols. There are protocols between each of several
functional layers and the corresponding layers at the other end of a communication. Both
end points must recognize and observe a protocol. Protocols are often described in an
industry or international standard. On the Internet, there are the TCP/IP protocols,
consisting of:
Pwebstats:
Pwebstats software generates reports which include statistical
information, as well as colorful graphs, that show market trends, website
usage, and much more!
Router:
On the Internet, a router is a device or, in some cases, software in a computer, that
determines the next network point to which a packet should be forwarded toward its
destination. The router is connected to at least two networks and decides which way to send
each information packet based on its current understanding of the state of the networks it
is connected to. A router is located at any gateway (where one network meets another),
including each Internet point-of-presence. A router is often included as part of a network
switch.
SMTP:
Simple Mail Transfer Protocol - The standard e-mail protocol on the
Internet. It is a TCP/IP protocol that defines the message format and the
message transfer agent (MTA), which stores and forwards the mail. SMTP was
originally designed for only ASCII text, but MIME and other encoding
methods enable program and multimedia files to be attached to e-mail
messages.
SMTP servers route SMTP messages throughout the Internet to a mail server,
such as POP3 or IMAP4, which provides a message store for incoming mail.
SNTP:
Short for Simple Network Time Protocol, a simplified version of Network Time Protocol (NTP)
SPAM:
Unsolicited e-mail or inappropriate commercial messages posted to
Internet newsgroups or mailing lists, especially when tlie ad is not
related to that newsgroup's designated topic.
SSL:
Secure Socket Layer enables credit card numbers, phone numbers and other
important, private information to be securely transferred across the
internet. SSL allows your customer's browser to connect to your website
and negotiate a secure communication channel.
Secure Socket Layer (SSL) is an emerging standard developed by Netscape
Communications to transfer information securely across the Internet. SSL
will enable your customer's browser to connect to your website and
transparently negotiate a secure communication channel. Once this
connection has been made, information (i.e. credit card numbers) can be
exchanged securely.
Static IP / Dynamic IP Address:
A static IP is a number (in the form of a dotted quad) that is assigned to a
computer by an Internet Service Provider (ISP) to be its permanent address on the Internet.
Computers use IP addresses to locate and talk to each other on the Internet, much the same
way people use phone numbers to locate and talk to one another on the telephone. When you
want to visit whatis.com, your computer asks a domain name system (DNS) server (think
telephone information operator) for the correct dotted quad number (think phone number) for
imbris.com and your computer uses the answer it receives to connect to the imbris.com
server.
Sub-Domains:
In addition to a domain name, some companies choose to further
distinguish their web pages with a sub-domain. A typical use for a
sub-domain would be a large company such as IBM that has numerous
locations and divisions around world. In addition to ibm.com, IBM also has
austin.ibm.com. Sub-domains are a good way to have several sites on the
Internet without having to pay for multiple domain names.
Subnet:
A subnet (short for "subnetwork") is an identifiably separate part of an
organization's network. Typically, a subnet may represent all the machines at one
geographic location, in one building, or on the same local area network (LAN). Having an
organization's network divided into subnets allows it to be connected to the Internet with
a single shared network address. Without subnets, an organization could get multiple
connections to the Internet, one for each of its physically separate subnetworks, but this
would require an unnecessary use of the limited number of network numbers the Internet has
to assign. It would also require that Internet routing tables on gateways outside the
organization would need to know about and have to manage routing that could and should be
handled within an organization. The Internet is a collection of networks whose users
communicate with each other. Each communication carries the address of the source and
destination networks and the particular machine within the network associated with the user
or host computer at each end. This address is called the IP address (Internet Protocol
address). This 32-bit IP address has two parts: one part identifies the network (with the
network number) and the other part identifies the specific machine or host within the
network (with the host number). An organization can use some of the bits in the machine or
host part of the address to identify a specific subnet. Effectively, the IP address then
contains three parts: the network number, the subnet number, and the machine number.
Switch:
In telecommunications, a switch is a network device that selects a path or circuit for
sending a unit of data to its next destination. A switch may also include the function of
the router, a device or program that can determine the route and specifically what adjacent
network point the data should be sent to. In general, a switch is a simpler and faster
mechanism than a router, which requires knowledge about the network and how to determine
the route.
A network's paths can be used exclusively for a certain duration by two or more parties and
then switched for use to another set of parties. This type of "switching" is known as
circuit-switching and is really a dedicated and continuously connected path for its
duration. Today, an ordinary voice phone call generally uses circuit-switching. Most data
today is sent, using digital signals, over networks that use packet-switching. Using
packet-switching, all network users can share the same paths at the same time and the
particular route a data unit travels can be varied as conditions change. In
packet-switching, a message is divided into packets, which are units of a certain number of
bytes. The network addresses of the sender and of the destination are added to the packet.
Each network point looks at the packet to see where to send it next. Packets in the same
message may travel different routes and may not arrive in the same order that they were
sent. At the destination, the packets in a message are collected and reassembled into the
original message.
T3 Connection:
Connections to the Internet vary widely in capacity. A typical home user
connects at 28,800 bits per second, or 28.8kbps. A typical office might
have a slightly faster connection of 128kbps. A large business might even
have a 1,550kbps connection, which is also known as a T1 (or terrestrial
backbone connection). IMBRIS, Inc. uses connections which are 29 times
faster than a T1 : T3 connections that connect to the Internet
at 45,000 bits per second! And to ensure complete reliability and peak
performance, IMBRIS, Inc. maintains multiple T3s (with multiple,
high-speed connections traffic is routed over whichever link is
"closer" to it's destination). The connections are constantly monitored,
and future bandwidth needs are forecast months in advance so there is
never a shortage of capacity.
TCP/IP:
Transmission Control Protocol/Internet Protocol - The basic
protocols that enable computer communications across the
Internet. Co-created by Vinton G. Cerf and Robert E. Kahn.
Upload:
The act of sending a file to the Internet or a server.
IMBRIS, Inc. clients can upload new website content 24-hours a
day. Using FTP, or File Transfer Protocol, you will be able to make these
changes on your computer system and upload them at your convenience.
Upstream:
This term refers to the path of data from your computer to the
Internet.
URL / URI Uniform Resource Locator:
Uniform Resource Locator / Uniform Resource Identifier -
This is the equivalent of having the phone number of a place vou want to
call. You will constantly use URLs with your Internet software to identify
the protocol, host name and file name of Internet resources vou want.
Usenet:
Another name for Internet Newsgroups. A distributed bulletin
board system running on news servers.
Virtual Secure Server:
Secure web pages are delivered on the web using SSL (Secure Sockets
Layer) technology. The URLs for secure web pages are prefaced by
"https" instead of the normal "http".
Virtual FTP Server:
Just like the web and mail, FTP (File Transfer Protocol) services can
also be "virtualized". E-Commerce Builder includes a virtual FTP server,
which can be accessed with the URL ftp://ftp.yourdomain.com. The FTP
service is a great way to distribute files to clients or the public.
24 / 7 Network Monitoring:
All IMBRIS, Inc. sites -- and their Internet connections -- are
monitored 24 hours a day, 7 days a week.