Ø THE INTERNET AND STANDAR
The Internet is a worldwide, publicly accessible network of
networks.
The way people interact, share information, and even do
business is changing to keep up with the continuous evolution of this global
network. The Internet is creating a wider audience and consumer base for
whatever message, product, or service can be delivered.
Some of the business uses of the Internet include:
ü
E-Commerce
ü
Communications
ü
Collaboration and training
Ø ISP AND SERVICE
An ISP is a company or organization through which a subscriber
obtains Internet access.
ISP may also offer other services to customers,
including:
ü Equipment
co-location
A business may opt to have some or all
internal network equipment physically located on the ISP premises.
ü Web
hosting
The ISP provides
the server and application software for storing web pages and web content for
the business website.
ü FTP
The ISP provides
the server and application software for the FTP site of a business.
ü Applications
and media hosting
The ISP provides
the server and software to allow a business to provide streaming media such as
music, video, or applications such as online databases.
ü Voice
over IP
A business can
save on long distance telephone charges, especially for internal calls between
geographically distant offices, by using Voice over IP (VoIP).
ü Technical
support
Many businesses
do not have the in-house technical expertise to manage large internal networks.
Some ISPs provide technical support and consulting services for an additional
fee.
ü Point
of Presence (POP)
ü A
business has the option of connecting to the ISP through POP, using a variety
of access technologies.
Ø
DELIVERING
INTERNET SERVICE TO AND USER
The main connection methods used by home and small business
users are:
ü Dialup
access
Dialup access is
an inexpensive option that uses any phone line and a modem. To connect to the
ISP, a user calls the ISP access phone number. Dialup is the slowest connection
option, and is typically used by mobile workers and in areas where higher speed
connection options are not available.
ü DSL
Digital
subscriber line, or DSL, is more expensive than dialup, but provides a faster
connection. DSL also uses telephone lines, but unlike dialup access, DSL
provides a continuous connection to the Internet. This connection option uses a
special high-speed modem that separates the DSL signal from the telephone
signal and provides an Ethernet connection to a host computer or LAN.
ü Cable
modem
A cable modem is
a connection option offered by cable television service providers. The Internet
signal is carried on the same coaxial cable that delivers cable television to
homes and businesses. A special cable modem separates the Internet signal from
the other signals carried on the cable and provides an Ethernet connection to a
host computer or LAN.
ü Satellite
Satellite
connection is an option offered by satellite service providers. The user's
computer connects through Ethernet to a satellite modem that transmits radio
signals to the nearest Point of Presence, or POP, within the satellite network.
· BANDWIDTH
Bandwidth is measured in bits per second (bps). Higher
bandwidth speeds are measured in kilobits per second (kbps), megabits per
second (Mbps), or gigabits per second (Gbps).
There are three main types of high-bandwidth connection
options that are used by businesses:
ü
T1 connections transmit data up to 1.544 Mbps.
ü
T3 connections transmit data up to 45 Mbps.
ü Metro Ethernet offers a wide range of
high-bandwidth options, including Gbps links.
Metro Ethernet allows the transfer of large amounts of data faster and
less expensively than other high-bandwidth connection options.
Ø INTERNET HIERARCHICAL
The Internet has a hierarchical structure. At the top of
this hierarchy are the ISP organizations. The ISP POPs connect to an Internet
Exchange Point (IXP). In some countries, this is called a Network Access Point
(NAP). An IXP or NAP is where multiple ISPs join together to gain access to
each other's networks and exchange information.
The Internet backbone is like an information super highway
that provides high-speed data links to interconnect the POPs and IXPs in major
metropolitan areas around the world. The primary medium that connects the
Internet backbone is fiber-optic cable.
ISP level access to the Internet backbone:
ü
Tier 1 ISPs are the top of the hierarchy. Tier 1
ISPs are huge organizations that connect directly with each other through
private peering, physically joining their individual network backbones together
to create the global Internet backbone.
ü
Tier 2 ISPs are the next tier in terms of
backbone access. Tier 2 ISPs can also be very large, even extending across
several countries, but very few have networks that span entire continents or
between continents.
ü
Tier 3 ISPs are the farthest away from the
backbone. Tier 3 ISPs are generally found in major cities and provide customers
local access to the Internet. Tier 3 ISPs pay Tier 1 and 2 ISPs for access to
the global Internet and Internet services.
Ø USING TOOLS TO MAP THE INTERNET
The ping command sends an ICMP (Internet Control Message
Protocol) echo request packet to the destination address and then waits for an
echo reply packet to return from that host. ICMP is an Internet protocol that
is used to verify communications.
To use the ping command, enter the following command at the
Cisco command line interface (CLI) router prompt or at the Windows command
prompt:
ping <ip address>
where <ip address> is the IP address of the
destination device.
Ø ISP REQUIREMENT
Some of the devices required to
provide services include:
ü Access
devices that enable end users to connect to the ISP, such as a DSL Access
Multiplexer (DSLAM) for DSL connections, a Cable Modem Termination System
(CMTS) for cable connections, modems for dialup connections, or wireless
bridging equipment for wireless access.
ü Border
gateway routers to enable the ISP to connect and transfer data to other ISPs,
IXPs, or large business enterprise customers.
ü Servers
for such things as email, network address assignment, web space, FTP hosting,
and multimedia hosting.
ü Power
conditioning equipment with substantial battery backup to maintain continuity
if the main power grid fails.
ü High
capacity air conditioning units to maintain controlled temperatures.
Loss of customers directly
translates to loss of income for an ISP. For this reason, it is important that
the ISP provides a reliable and scalable network.
Scalability is the capacity of a
network to allow for future change and growth. Scalable networks can expand
quickly to support new users and applications without affecting the performance
of the service being delivered to existing users.
The most scalable devices are
those that are modular and provide expansion slots for adding modules.
Different modules can have different numbers of ports. In the case of a chassis
router, some modules also offer different interface options, allowing for
different connection options on the same chassis.
It is important for ISPs to
provide a reliable and scalable network.
Scalability is the capacity of a
network to allow for future change and growth. Scalable networks can expand
quickly to support new users and applications without affecting the performance
of the service being delivered to existing users.
The most scalable devices are
those that are modular and provide expansion slots for adding modules.
Different modules can have different numbers of ports. In the case of a chassis
router, some modules also offer different interface options, allowing for
different connection options on the same chassis.
Ø ROLES AND RESPONSILIBITIES WITHIN AN ISP
Each of the network support
service teams have their own roles and responsibilities:
ü Customer
Service receives the order from the customer and ensures that the specified
requirements of the customer are accurately entered into the order tracking
database.
ü Planning
and Provisioning determines whether the new customer has existing network
hardware and circuits and if new circuits need to be installed.
ü The
On-site Installation is advised of which circuits and equipment to use and then
installs them at the customer site.
ü The
Network Operations Center (NOC) monitors and tests the new connection and
ensures that it is performing properly.
ü The
Help Desk is notified by the NOC when the circuit is ready for operation and
then contacts the customer to guide them through the process of setting up
passwords and other necessary account information.
Postingan
0 komentar:
Posting Komentar