Network Planning and Documentation

Network planning and documentation is an essential process to ensure the effective design, implementation, and maintenance of a network. It involves creating a strategic plan that defines the objectives, requirements, and resources needed to build and manage a network efficiently and securely. It involves identifying the specific needs of the organization, such as the number of users, the services required, and the expected volume of traffic. Likewise, it also involves evaluating the available technologies and selecting the most appropriate ones to meet the needs of the network.

Network documentation: diagrams, inventory of equipment

Maintaining network documentation is important because if part or all of the network is down, this can have a major negative impact on the business. Documentation can help us take a more systematic approach to troubleshooting the problem to get it back up and running as quickly as possible.

For a network administrator to monitor and resolve these network problems, it is necessary to maintain documentation including

• Configuration files, including network and end system configuration files.
• Physical and logical topology diagrams.

With this information, a network administrator can effectively diagnose and correct network problems based on the design and expected performance of the network under normal operating conditions.

Network configuration files

These files contain accurate and up-to-date records of the hardware and software used on a network. Among these files should be a table for each network device used with all relevant information about that device.

The device name and model	Interface name	Mac Address	IPV4 Address	IPV6 Address
R1 Cisco 1941 152-A.M1	G0/0	0071.8580.A350	192.168.5.1/24	2001:ad4:cafe:10::1/64
	G0/1	0071.8580.A351.	192.168.10.1	2001:ad4:cafe::11::1/64

We can also have a list of the end system configuration files, these are focused on the hardware and software used in the end system devices, such as servers, network management consoles, and user workstations.

This list will help us, as a misconfigured end system can impact negatively on the overall network performance. It is very useful to have a baseline log showing the hardware and software used on these devices for troubleshooting purposes.

Device Name	Operating System	MAC Address	IP Address	Default Gateway	DNS Server	Network Applications
PC2	Windows 10	5475:DB04.9A3E	192.168.15.5/24	198.168.15.1	192.168.15.15	192.168.15.15
192.168.20.254/24	192.168.20.1	192.168.20.1	192.168.20.1	2200:DBB::ACAD:1::99	HTTP, FTP

Network Topology Diagrams

Network topology diagrams keep track of the location, function, and status of all network devices. There are two types of topologies:

• Physical topology.

A physical network topology shows the physical distribution of devices connected to the network. To solve physical layer problems, it is necessary to know how the devices are physically connected. The information recorded in the diagram generally includes:

Device type:

• Model and manufacturer
• Operating system version
• Cable type and identifier
• Cable specification
• Connector type
• Cable ends
• Logical topology

The logical network topology illustrates how devices logically connect to the network, i.e. how devices transfer data across the network when communicating with other devices.

Symbols are used to represent network elements such as routers, servers, hosts, VPN concentrators, and security devices. Additionally, connections between various sites can be shown, but do not represent actual physical locations. Information recorded in a logical network diagram may include the following:

• Device identifiers
• IP address and prefix lengths
• Interface identifiers
• Connection type
• DLCI for virtual circuits
• Site-to-site VPN
• Routing protocols
• Static routes
• Data link protocols
• WAN technologies used

Network growth planning

It is also important to understand that one of the most important characteristics in the design of a network is that it can be scalable. This means that it can be planned for future growth.

This will allow us to ensure that the quality of service of the network is optimal and can continue to function despite the high demand for user growth, thus, designing a network that works flawlessly and adapts to updates and changes will solve problems related to security, functionality, and efficiency.

For a network to be scalable, it is necessary to take into account the ability to adapt, to focus on increasing network capacity by adding more access points, or to generate a hierarchy of networks.

The use of cloud services, combining several ports into one, and looking for a wireless solution will also be key to expanding and achieving scalability in distributed systems.

To support a large, medium, or small network, the network designer must develop a strategy that makes the network available and scalable efficiently and easily. A basic network design strategy includes the following recommendations:

Use expandable, modular equipment or clustered devices that can be easily upgraded to increase capabilities. Device modules can be added to existing equipment to support new features and devices without requiring major equipment upgrades. Some devices can be integrated into a group to act as a single device to simplify management and configuration.

Best practices for network management.

Design a hierarchical network that includes modules that can be added, upgraded, and modified as needed without affecting the design of the other functional areas of the network. For example, create a separate access layer that can be expanded without affecting the basic campus network distribution and layers.

Create an IPv4 and IPv6 addressing hierarchical strategy. Careful address planning eliminates the need to re-address the network to support additional users and services.

Choose multi-layer routers or switches to limit broadcasts and filter other unwanted network traffic. Use Layer 3 devices to filter and reduce traffic to the network core.

We can achieve all this with good network planning and management.

Network management systems can manage network devices such as switches, routers, access points, and wireless controllers from a centralized or remote location.

Network administrators or MSPs can monitor network operations by accessing this server, which gives them a great deal of control without having to go on-site. Good management can allow us to:

• Clear network visibility: The IT professional should get a clear picture of all connected devices on the network, observe data flow, and quickly identify and remedy problems that reduce network performance and can lead to failures.
• **More efficient use of IT resources: We can implement tools that reduce the amount of manual labor required. This reduces labor costs and frees up technicians to focus on more important projects or other tasks.
• Future infrastructure needs: Network monitoring systems show how network components have performed over some time, giving us insight into the future. These reports can be analyzed to help anticipate when the organization may need to consider upgrading or implementing a new IT infrastructure.
• Increased protection against security threats: Network monitoring establishes a baseline of a network's performance. This makes it easier to detect unusual changes in network behavior, such as unexplained increases in network traffic levels. When IT can quickly identify potential cybersecurity issues, it can often intervene before the threat becomes costly.

💡QUIZ

1. What is the main function of a firewall in a computer network? a) Manage network bandwidth. ✅ b) Protect the network by filtering unauthorized traffic. c) Provide IP addresses to devices on the network. d) Optimize the network topology.

2. How many layers make up the OSI Model (Open Systems Interconnection Model)? a) 4 b) 5 c) 6 d) 7 ✅

3. Which of the following network devices operates at Layer 2 (data link layer) of the OSI Model and is used to interconnect network segments on the same subnet? a) Router b) Concentrator (hub) c) Switch ✅ d) Firewall

4. Which of the following network topologies uses a central node to connect all devices on the network, forming a star structure? a) Bus topology b) Ring topology c) Mesh topology d) Star topology ✅

5. What does the acronym "DMZ" represent in the context of network security? a) Direct Access Zone b) Data Maintenance Area c) Demilitarized Zone ✅ d) Maximum Zoning Zone