Content Overview Despite current
information technology (IT) investments, many organizations
find that vital networked resources, applications, and
information assets remain largely unlinked. In fact, it is
common for organizations to have hundreds of applications and
databases that cannot communicate with each other. This is due
in part to increasing and often unexpected demands from
internal and external customers. Many enterprises have to
deploy new technologies and applications quickly. This often
leads to the deployment of disparate systems. The result of
these new deployments is an inability to share information
efficiently across the organization. For example, sales,
customer service, or purchasing departments cannot access
customer records easily without creating different overlay
networks that join applications and information. Many
organizations have found that unplanned expansion has left them
with multiple systems and distributed resources that are
uncoordinated and under utilized. The disparate systems are
also difficult and costly to manage. The Cisco Intelligent
Information Network (IIN) vision helps IT organizations correct
these problems and meet new challenges including
service-oriented architectures, web services, and
virtualization using network architectures. An intelligent
network builds on an existing infrastructure foundation and
turns the traditional IT “cost center” into a strategic tool
that helps enable sophisticated IT functionality, such as
virtualization, telepresence, application integration, and
optimization, that streamlines IT processes. Regardless of the
size and type of business, Cisco provides architecture roadmaps
to help build a more resilient, adaptive, and intelligent
network. This introductory lesson explains conceptual network
models that affect remote access networks and the services that
run on those networks. The topics in this lesson explain the
vision Cisco has of the IIN and the Cisco Service-Oriented
Network Architecture (SONA). The lesson also presents the
remote connectivity infrastructure and services within the
Cisco Enterprise Architecture to explain the diversity of
access options for branch offices and teleworkers with a focus
on security. Web Links Intelligent Information
Network; Building Business Transparency and Agility
http://www.cisco.com/warp/public/779/largeent/
landingPage/iin/pdf/cisco_refreshbrochure_05132_r2.pdf
Intelligent Information Network Introductory
Homepage
http://cisco.com/en/US/netsol/ns648/networking
_solutions_intelligent_information_network_home.html
What is IIN?
http://www.cisco.com/en/US/netsol/ns650/networki
ng
_solutions_market_segment_solution.html At-a-Glance:
What is Cisco SONA?
http://www.cisco.com/application/pdf/en/us/guest
/
netsol/ns477/c643/cdccont_0900aecd8039b324.pdf Service
Orientated Network Architecture
http://cisco.com/en/US/netsol/ns629/networking
_solutions_market_segment_solutions_home.html Cisco
Enterprise Architectures
http://www.cisco.com/en/US/netsol/ns517/networking
_solutions_market_segment_solutions_home.html Cisco
Enterprise Architectures - Poster
http://www.cisco.com/application/pdf/en/us/guest/
netsol/ns477/c643/cdccont_0900aecd8039e0ea.pdf Cisco
Enterprise Campus Architecture
http://www.cisco.com/en/US/netsol/ns340/ns394/
ns431/networking_solutions_packages_list.html Cisco
Enterprise Branch Architecture
http://www.cisco.com/en/US/netsol/ns477/
networking_solutions_packages_list.html Cisco Enterprise
Data Center Architecture
http://www.cisco.com/en/US/netsol/ns340/ns394/
ns224/networking_solutions_packages_list.html SAFE White
Papers
http://cisco.com/en/US/netsol/ns340/ns394/
ns171/ns128/networking_solutions_package.html Cisco
Enterprise Teleworker Architecture
http://www.cisco.com/en/US/netsol/ns340/ns394/
ns430/networking_solutions_packages_list.html Cisco
Enterprise WAN/MAN Architectures
http://www.cisco.com/en/US/netsol/ns483/
networking_solutions_packages_list.html
Content
1.1 Enterprise Networking 1.1.1
Hierarchical Network Model Traditional network design uses
a three-layer hierarchical model. The model provides a modular
framework that allows flexibility and makes implementation and
troubleshooting easy. Figure shows how the hierarchical model
divides networks or their modular blocks into the access,
distribution, and core layers. Each layer has specific
features: - Access layer: The access layer
grants local or remote users access to network devices. In a
networked campus, the access layer most often uses switched LAN
devices with ports that provide connectivity to workstations
and servers. In the WAN environment, the access layer at remote
sites provides access to the corporate network across WAN
technology.
- Distribution layer: The
distribution layer aggregates the wiring closets using switches
to segment workgroups and isolate network problems in a campus
environment. Similarly, the distribution layer aggregates WAN
connections at the edge of the campus and provides policy-based
connectivity.
- Core layer: The core layer or
backbone design switches packets as fast as possible. Because
the core layer is critical for connectivity, this layer must
provide a high level of availability and adapt to changes very
quickly.
Network designers can apply the
hierarchical model to any network type including LANs, WANs,
wireless LANs (WLANs), metropolitan-area networks (MANs), and
virtual private networks (VPNs) and to any modular block of the
Cisco networking model. Figure represents an enterprise network
using the traditional hierarchical model design.
Interactive Media Activity Point and Click: Layered
Design Model
In this media activity, the students
learn characteristics of the Layered Design Model. This is a
point-and-click activity where the students click their
choice.
Content 1.1 Enterprise Networking
1.1.2 Cisco Enterprise Architecture The
hierarchical layered approach to network design divides
networks into access, distribution, and core layers. This
approach treats the campus and the WAN as separate entities.