DO NOT design your network like this!! // FREE CCNA // EP 6

Summary

In this video, the presenter highlights the importance of network design, focusing on the dangers of a poor setup that can lead to single points of failure. Using examples like daisy-chained switches, the speaker introduces better architectures, specifically the two-tier and three-tier designs. The two-tier setup is suitable for simpler networks, while the three-tier model is ideal for large campus environments. Redundancy, multi-layer switches, and proper tiered architecture are emphasized as key to ensuring robust, high-speed connections. The video concludes by encouraging viewers to explore their own company's network design and join the community for further learning.

Takeaways

• 😀 **Single points of failure** should be avoided in business networks to ensure reliability and resilience.
• 😀 **Home-style networks** with a single router and daisy-chained switches are acceptable for personal use but dangerous for business environments.
• 😀 **Two-tier network architecture** involves an access layer for device connectivity and a distribution layer for routing and policy enforcement.
• 😀 **The two-tier architecture** can work in smaller environments but is not ideal for large, multi-building campuses.
• 😀 **Three-tier architecture** adds a core layer that serves as the high-speed backbone, connecting different distribution layers and ensuring network scalability and redundancy.
• 😀 **Redundancy** is critical in network design: multiple connections and devices are required to minimize failure risks and ensure reliability.
• 😀 **Campus networks** can benefit from the three-tier design, especially in scenarios with numerous buildings requiring high-speed, low-latency connectivity.
• 😀 **Core layer** handles the backbone traffic between buildings, making it a crucial element for large campuses with high-performance requirements.
• 😀 **Layer 3 switches** play a key role in routing between VLANs, providing high-throughput and minimizing latency.
• 😀 Join NetworkChuck's **Discord community** for networking advice and CCNA preparation, and connect with thousands of professionals.
• 😀 **Redundant network design** increases costs but is necessary for maintaining uptime and performance in business-critical environments.

Q & A

What is a single point of failure in network design?

A single point of failure refers to any component or link in the network that, if it fails, causes a significant portion of the network or services to go down. For example, a single switch or cable can disrupt the entire network if it's the only path between critical devices.

Why is it bad to daisy chain switches together in network design?

Daisy chaining switches creates a risk of a single point of failure. If one switch or cable in the chain fails, it could disconnect all devices downstream, causing network downtime. Proper redundancy and diverse paths should be incorporated to prevent this.

What is the purpose of a multi-layer switch (Layer 3 switch)?

A multi-layer switch, or Layer 3 switch, combines the functionality of both switches and routers. It can forward traffic based on both MAC (Layer 2) and IP (Layer 3) addresses, making it faster and more efficient for routing within the network.

What is a two-tier network architecture?

A two-tier architecture consists of two layers: the access layer and the distribution layer. The access layer provides connectivity for devices (computers, printers, etc.), while the distribution layer handles routing, security policies, and network management between access switches.

What role does the distribution layer play in network design?

The distribution layer acts as an intermediary between the access layer and the core layer. It handles tasks like routing, inter-VLAN communication, access control lists (ACLs), and packet forwarding across the network.

How does a three-tier network architecture differ from a two-tier one?

A three-tier architecture adds a core layer between the distribution and access layers. The core layer provides high-speed backbone connectivity, helping to manage traffic across larger, more complex networks, especially for multiple buildings or large campuses.

What are the benefits of having redundancy in a network?

Redundancy in network design ensures high availability by providing alternative paths for traffic. If one device or link fails, another can take over, minimizing downtime and maintaining continuous network operation.

What is the difference between a core layer and a distribution layer in network architecture?

The core layer is the backbone of the network, handling high-speed traffic and low-latency operations between distribution layers. The distribution layer, on the other hand, manages routing, filtering, and policies at a slightly lower speed but with higher volume handling capabilities.

Why is it important to use powerful switches in the distribution layer?

The distribution layer needs powerful switches because they handle large volumes of traffic and complex tasks like routing and inter-VLAN communication. Using high-performance switches ensures smooth traffic flow without bottlenecks or delays.

What is the function of the core layer in a network?

The core layer provides fast, reliable, and redundant high-speed connections across large networks or campus environments. It serves as the network's backbone, ensuring minimal latency and maximum uptime for critical operations.