Chapter3 : Lab 3.5.5 Analyzing an Existing Network

Step 1: Document and confirm existing network topology, addressing, and naming schemes

a. Examine the existing network topology diagram.

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Record the current addressing scheme in a table.

Associate device names with addresses on the table.

b. Highlight any inconsistencies in the naming and addressing schemes.

For example:

• Naming some devices by location and others by function

• Inconsistent or confusing use of abbreviations

• Some gateway addresses as the first address of a subnet, others as the last address

c. Use word processing software to create a Current Network document.

Step 2: Identify those parts of the existing network that currently meet the project technical requirements

a. Examine the network topology and specifications.

Record which current features meet the technical requirements of the proposed network upgrade.

• Capacity (bandwidth, address ranges, VLANs)

• Redundant links

• Router and switch interfaces and ports

• Router and switch feature sets, memory, and processing capability

• WAN

• Wireless

• QoS

b. Include these strengths and capabilities in your Current Network document.

Potential strengths may include:

• New wiring and adequate communications closets

• Adequate space for a new data center

• Servers and PCs are current models and will not need replacement

• Some existing network switches and routers can be used in the new design

Step 3: Identify those parts of the existing network that can be scaled to meet the project

technical requirements

a. Examine the network topology and specifications.

Record which current features do not meet the technical requirements of the proposed network

upgrade but can be scaled within the capacity of the network to do so.

• Capacity (bandwidth, address ranges, VLANs)

• Redundant links

• Router and switch interfaces and ports

• Router and switch feature sets, memory, and processing capability

• WAN

• Wireless

• QoS

b. Include these scalable features and capabilities in your Current Network document.

Step 4: Identify those parts of the existing network that do not to meet the project technical requirements

a. Examine the network topology and specifications.

Record which current features do not meet the technical requirements of the proposed network

upgrade and what additional networking resources are required.

• Capacity (bandwidth, address ranges, VLANs)

• Redundant links

• Router and switch interfaces and ports

• Router and switch feature sets, memory, and processing capability

• WAN

• Wireless

• QoS

b. Include these weaknesses and shortfalls in your Current Network document.

Possible weaknesses include:

• Flat network design

• Insufficient bandwidth at Distribution Layer, no true Core Layer

• Servers poorly located

• Multiple networks, difficult to maintain

• Poor IP addressing structure

• No dedicated bandwidth for WAN connectivity

• Limited wireless implementation

• Limited security implementations

Step 5: Obtain agreement and authorization from the company to continue with the network upgrade design

a. Finalize the Current Network document so that the strengths and shortfalls are clearly and precisely

presented.

b. Discuss and review your Current Network document with another student to ensure that it clearly

states which parts of the network meet the technical requirements of the upgrade project and which

parts do not. Amend the document as necessary to clarify any areas that could be misunderstood. At

this stage of the network design process, a meeting with the FilmCompany management would be

held to obtain their agreement and authorization to continue with the design of the upgrade.

c. Save and retain your Current Network document so that it can be incorporated with the previous

documents to complete this network design case study.

Step 6: Reflection

Consider the resources and information that will facilitate the task of analyzing a current network.

• Having up-to-date documentation showing such information as addressing, device names,

VLAN allocations, switch port assignments

• Systematic and consistent host names, descriptions, and addressing schemes

• Software tools that record data flows and device identification

• Efficient and accurate fault and incidence reporting and clearance documentation to highlight

and record problems

• sistematis dan nama host yang konsisten, deskripsi, dan skema pengalamatan
• Software tools yang merekam aliran data dan identifikasi perangkat