Network Tier Architecture
Tier: A tier is a distinct part of hardware/ software.
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(business, consumers, etc)
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° Single Tier Systems
5: A single computer that
contains a database and
a front-end (GUI) to
access the database is
known as Single Tier
System. Generally, this
type of system is used in
<-: There is one computer which stores all of the company's
data on a single database.
€-: The interface used to interact with the database may be
part of the database or another program which ties into
the database itself.
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User interface User interface
3-tier and n-tier client-server database designs try to solve
these problems by simply transferring the application logic
from the client back to the server.
Multi-tier architecture (n-tier architecture) is a client-server
architecture in which an application is executed by more than
one distinct software agent.
For example, an application that uses middleware to service
data requests between a user and a database employs
multi-tier architecture. The most widespread use of "mu| ti-tier
architecture" refers to three-tier architecture
The client program has only User Interface (Ul) code
that talks, via a network, to the "middle tier" on
which the business and database logic sits. In turn the
middle tier talks, via a network, to the database. In
practice the middle tier can be placed, if necessary, on
the same machine as the database.
User interface I V User interface
I logic (GUI)
logic (GUI) V n. ..4-. ..l. ... ..-. -.
] C Business logic
> A Tier 2 Network is an
Internet service provider
who engages in the practice
of peering with other
networks, but who still
purchases IP transit to reach
some portion of the Internet.
> Tier 2 providers are the most common providers on the
Internet as it is much easier to purchase transit from a Tier 1
network than it is to peer with them and then attemptto push
into becoming a Tier 1 carrier.
> The term Tier 3 is sometimes also used to describe networks
who solely purchase IP transit from other networks (typically
Tier 2 networks) to reach the Internet.
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