Chapter 1 Flashcards
Business forces affecting decisions for the
enterprise network include the following:
■Return on investment: Companies expect a return
(be it cost savings or increased
productivity) on its investments of network
infrastructure. The solutions need to use
technology to work within a business solution.
■ Regulation: Companies need to meet industry
regulations; for example, the Health
Insurance Portability and Accountability Act
(HIPAA) for the health insurance industry
and Payment Card Industry Data Security Standard
(PCI DSS) for the credit card
industry.
■ Competitiveness: To maintain a competitive
edge, companies need to use technology
to make them more competitive than other
businesses.
The technology forces affecting decisions for the
enterprise network are
■ Removal of borders: Traditional network
boundaries have been removed. Access to
network resources need to be enabled from branch
offices, teleworkers, home offices,
mobile devices, customers, and partner networks.
■ Virtualization: Allows for the maximization of
efficiencies through the reduction of
hardware, power consumption, heating and cooling
costs, facilities space, and management
effort. Virtualization and its benefits are a key
goal for almost all organization.
It has gained popularity by industry leaders such
as VMware.
■ Growth of applications: Customers continue to
ask for new products, service offerings,
improved customer service, greater security, and
customization flexibility—all
at a lower cost.
IT optimization areas are divided into three
groups:
■ Data center
■ Network
■ Applications
Cisco has created an interwoven framework to
create three architectures for each group
that provides for optimization at an individual
level and the integration with other areas:
■Borderless networks architecture
■ Collaboration architecture
■ Data center/virtualization architecture
Borderless Networks Architecture
Cisco Borderless Network Architecture is a next-generation solution that enables connectivity
to anyone and anything, anywhere, and at any time. The connectivity needs to be
secure, reliable, and seamless. The borderless architecture optimizes both business and
network performance.
As shown in Figure 1-2, the Cisco borderless network architecture blueprint consists of
four major blocks:
■ Policy and Control: Policies are applied to all users and devices across the architecture.
■ Network Services: These services include resiliency and control. Cisco Energy-
Wise and Medianet provide capabilities to borderless networks.
■ User Services: These services include mobility, performance, and security.
■ Connection Management: This block delivers secure access anytime and anywhere,
regardless of how the network is accessed.
Collaboration Architecture
Cisco’s collaboration architecture is composed of three layers:
■ Communication and Collaboration Applications: This layer contains conferencapplications,
and TelePresence.
■ Collaboration Services: This layer contains services that support the collaboration
applications: presence, location, session management, contact management, client
frameworks, tagging, and policy and security management.
■ Infrastructure: This layer is responsible for allowing collaboration anytime, from
anywhere, on any device. It includes virtual machines, the network, and storage.
Data Center/Virtualization Architecture
Cisco’s data center/virtualization architecture is built upon Cisco Data Center 3.0. It comprises
a comprehensive set of virtualization technologies and services that bring the network,
computing, storage, and virtualization platforms together. Figure 1-3 shows the
architecture framework for data centers.
Benefits of Cisco Network Architectures
Benefit Description
Functionality Supports organizational requirements
Scalability Supports growth and expansion of organizational tasks
Availability Provides services reliability, anywhere and anytime
Benefit Description
Performance Provides responsiveness, throughput, and utilization on a per-application
basis
Manageability Provides control, performance monitoring, and fault detection
Efficiency Provides network services and infrastructure with a reasonable operational
costs and appropriate capital investment
Prepare, Plan, Design, Implement, Operate, and
Optimize Phases
Cisco has formalized a network’s life cycle into six phases: Prepare, Plan, Design,
Implement, Operate, and Optimize. These phases are collectively known as PPDIOO.
The PPDIOO life cycle provides four main benefits:
■ It lowers the total cost of ownership by validating technology requirements and planning
for infrastructure changes and resource requirements.
■ It increases network availability by producing a sound network design and validating
the network operation.
■ It improves business agility by establishing business requirements and technology
strategies.
■ It speeds access to applications and services by improving availability, reliability, security,
scalability, and performance.
Actions That Lower the Cost of Ownership
Actions That Lower the Cost of Ownership
Identifying and validating technology requirements
Planning for infrastructure changes and resource requirements
Developing a sound network design aligned with technical requirements and business goals
Accelerating successful implementation
Improving the efficiency of the network and the staff that supports it
Reducing operating expenses by improving the efficiency of operation processes and tools
Actions That Increase Network Availability
Actions That Increase Network Availability
Assessing the state of the network and its ability to support the proposed design
Specifying the correct set of hardware and software releases and keeping them current
Producing a sound operations design and validating network operation
Staging and testing the proposed system before deployment
Improving staff skills
Proactively monitoring the system and assessing availability trends and alerts
Proactively identifying security breaches and defining remediation plans
Actions That Improve Business Agility
Actions That Improve Business Agility
Establishing business requirements and technology strategies
Readying sites to support the system that will be implemented
Integrating technical requirements and business goals into a detailed design and demonstrating
that the network is functioning as specified
Expertly installing, configuring, and integrating system components
Continually enhancing performance
Actions That Accelerate Access to Applications and Services
Actions That Accelerate Access to Applications and Services
Accessing and improving operational preparedness to support current and planned network
technologies and services
Improving service delivery efficiency and effectiveness by increasing availability, resource capacity,
and performance
Improving the availability, reliability, and stability, of the network and the applications that run
on it
Managing and resolving problems that affect the system and keeping software applications
current
Prepare Phase
The Prepare phase establishes organization and business requirements, develops a network
strategy, and proposes a high-level conceptual architecture to support the strategy. Techestablish
a financial justification for a network strategy.
Plan Phase
The Plan phase identifies the network requirements based on goals, facilities, and user
needs. This phase characterizes sites and assesses the network, performs a gap analysis
against best-practice architectures, and looks at the operational environment. A project
plan is developed to manage the tasks, responsible parties, milestones, and resources to do
the design and implementation. The project plan aligns with the scope, cost, and resource
parameters established with the original business requirements. This project plan is followed
(and updated) during all phases of the cycle.
Design Phase
The network design is developed based on the technical and business requirements obtained
from the previous phases. The network design specification is a comprehensive detailed
design that meets current business and technical requirements. It provides high
availability, reliability, security, scalability, and performance. The design includes network
diagrams and an equipment list. The project plan is updated with more granular information
for implementation. After the Design phase is approved, the Implement phase begins.
Implement Phase
New equipment is installed and configured, according to design specifications, in the Implement
phase. New devices replace or augment the existing infrastructure. The project
plan is followed during this phase. Planned network changes should be communicated in
change control meetings, with necessary approvals to proceed. Each step in the implementation
should includes a description, detailed implementation guidelines, estimated time
to implement, rollback steps in case of a failure, and any additional reference information.
As changes are implemented they are also tested before moving to the Operate phase.
Operate Phase
The Operate phase maintains the network’s day-to-day operational health. Operations include
managing and monitoring network components, routing maintenance, managing upgrades,
managing performance, and identifying and correcting network faults. This phase
is the design’s final test. During operation, network management stations should monitor
the network’s general health and generate traps when certain thresholds are reached. Fault
detection, correction, and performance monitoring events provide initial data for the optimize
phase.
Optimize Phase
The Optimize phase involves proactive network management by identifying and resolving
issues before they affect the network. The Optimize phase may create a modified network
design if too many network problems arise, to improve performance issues, or to resolve
application issues. The requirement for a modified network design leads to the network
life cycle beginning.
PPDIOO Network Life Cycle Phases
PPDIOO Phase Description
Prepare Establishes organization and business requirements, develops a network
strategy, and proposes a high-level architecture
Plan Identifies the network requirements by characterizing and assessing the
network, performing a gap analysis
Design Provides high availability, reliability, security, scalability, and performance
Implement Installation and configuration of new equipment
Operate Day-to-day network operations
Optimize Proactive network management; modifications to the design
Design Methodology Under PPDIOO
The following sections focus on a design methodology for the first three phases of the
PPDIOO methodology. This design methodology has three steps:
Step 1. Identifying customer network requirements
Step 2. Characterizing the existing network
Step 3. Designing the network topology and solutions
In Step 1, decision makers identify requirements, and a conceptual architecture is proposed.
This step occurs in the PPDIOO Prepare phase.
In Step 2, the network is assessed, and a gap analysis is performed to determine the infrastructure
necessary to meet the requirements. The network is assessed on function, performance,
and quality. This step occurs in the PPDIOO Plan phase.
In Step 3, the network topology is designed to meet the requirements and close the network
gaps identified in the previous steps. A detailed design document is prepared during
this phase. Design solutions include network infrastructure, Voice over IP (VoIP), content
networking, and intelligent network services. This set occurs in the PPDIOO Design phase.
Identifying Customer Design Requirements
To obtain customer requirements, you need to not only talk to network engineers, but also
talk to business unit personnel and company managers. Networks are designed to support
applications; you want to determine the network services that you need to support.
As shown in Figure 1-5, the steps to identify customer requirements are as follows:
Step 1. Identify network applications and services.
Step 2. Define the organizational goals.
Step 3. Define the possible organizational constraints.
Step 4. Define the technical goals.
Step 5. Define the possible technical constraints.
Characterizing the Existing Network
Step 1. Identify all existing organization information and documentation.
Step 2. Perform a network audit that adds detail to the description of the network.
Step 3. Use traffic analysis information to augment information on applications and
protocols used.
Top-Down Approach
Top-down design just means starting your design from the top layer of the OSI model and
working your way down. Top-down design adapts the network and physical infrastructure
to the network application’s needs. With a top-down approach, network devices and technologies
are not selected until the applications’ requirements are analyzed. To complete a
top-down design, the following is accomplished:
■ Analysis of application and organization requirements
■ Design from the top of the OSI reference model
■ Define requirements for upper layers (Application, Presentation, Session)
■ Specify infrastructure for lower OSI layers (transport, network, data link, physical)
■ Gather additional data on the network
