Things You Should Know about Modular Switches and Fixed Switches

Posted on Oct 17, 2023

In the world of networking infrastructure, switches play a crucial role in connecting devices and facilitating efficient data transmission. When it comes to switches, two common types are fixed switches and modular switches. Understanding the differences between these two types of switches can help network administrators make informed decisions when building or upgrading their network infrastructure.

What Is Modular Switch?

Modular switches are designed to accommodate various types of line cards, allowing for port connectivity in both copper and fiber networks. These line cards can be inserted into slots within a chassis, which also houses modules for functions like power supply, processing, and cooling. For example, NC8400-4TH is a 4-slot data center modular chassis switch that contains 2 types of line cards, 6 smart fans, and 4 hot-swappable power modules. Modular switches allow customization based on specific requirements, making them scalable and adaptable for future network expansions.

modular switch

Main Features of Modular Switches

    • Modular Architecture: One of the key features of modular switches is their modular architecture. They consist of a chassis or enclosure that can accommodate various modular components, such as line cards, power supplies, and control modules. This modular design allows for flexibility, scalability, and customization based on specific network requirements.

    • Scalability and Expansion: Modular switches are designed for scalability, allowing for easy expansion as network needs grow. Additional modules or line cards can be added to the chassis to increase the number of ports or enhance the switch's capabilities. This scalability makes modular switches suitable for enterprise networks, data centers, or environments with evolving connectivity demands.

    • Advanced Features and Functionality: Modular switches typically offer advanced features and functionality to meet the demands of modern networks. They often support advanced switching protocols, VLANs, QoS, multicast routing, and security features. These advanced capabilities enable efficient traffic management, improved network performance, and enhanced security.

    • Centralized Management: Modular switches often come with comprehensive management tools and software that allow for centralized management and configuration of the entire switch system. This simplifies network administration, monitoring, and troubleshooting tasks, improving overall network management efficiency.

What Is Fixed Switch?

Fixed switches, also known as fixed configuration switches or fixed port switches, are network switches that come with a predetermined and non-expandable number of ports. These switches have a fixed configuration, meaning that the number and type of ports are predetermined and can not be modified or upgraded once the switch is manufactured. For example, N8560-64C is a 64-port L3 data center fixed switch that has 64 x 100Gb QSFP28 ports.

fixed switch

Main Features of Fixed Switches

    • Fixed Configuration: Fixed switches have a fixed number of ports and a predetermined configuration that can not be modified or expanded. They come in various sizes, such as 8, 16, 24, or 48 ports, with different port types, such as Ethernet or Gigabit Ethernet.

    • Compact Size: Fixed switches are compact in size, taking up less physical space compared to modular switches. This makes them ideal for environments with limited space, such as small offices, branch locations, or home networks.

    • Specific Functionality: Fixed switches are often purpose-built with specific functionality in mind, such as access switches or distribution switches. Access switches are typically used to connect end-user devices, such as computers or printers, while distribution switches aggregate traffic from access switches and connect to the core network. This focused design ensures optimal performance for their intended use cases.

    • Energy Efficiency: Fixed switches are designed to be energy-efficient, consuming less power compared to modular switches. They are optimized to provide efficient network connectivity while minimizing energy consumption, resulting in lower energy costs.

Fixed Switches vs. Modular Switches

Both fixed and modular switches are suitable for legacy and modern fiber-optic networks. The choice between the two depends on various factors, such as network requirements, current architecture, compatibility with other devices, and more. Here are four key differences between fixed and modular switches.

Scalability and Adaptability

Fixed switches have a compact and self-contained design. They come with a fixed number of ports and a predetermined configuration that cannot be modified or expanded. Modular switches consist of a modular chassis or enclosure that can accommodate various modular components, such as line cards, power supplies, and control modules. This allows for customization, expansion, and flexibility in configuration.


Modular switches are generally more expensive than fixed switches due to their inclusion of line cards, power supplies, fan trays, and blades. However, modular switches often support multiple queues and thresholds per port, making upgrades to supervisor modules more cost-effective compared to upgrading all ports in a fixed switch when new features are released.


Since modular switches generally feature a high-speed common backplane module, more often than not, it is possible to obtain line-rate L2 and L3 switching on all ports of the entire chassis for packets of any size, resulting in a non-blocking configuration for all ports. It is difficult to realize such non-blocking configurations in fixed switches. Also, the manufacturing quality of fixed-format switches is lower than modular switches. Modular switches are designed, manufactured, and built for much higher MTBF and MTTR than a fixed format switch and this is reflected in better software defect ratios, and lower hardware failure rates.


Fixed switches are suitable for smaller networks with straightforward needs and limited budgets. Modular switches are more appropriate for medium and larger networks that require scalability, flexibility, advanced features, high availability, and greater customization options.

small data center

medium-sized IDC

Product Type Modular Switches Fixed Switches
Models NC8200-4TD NC8400-4TH N9510-64D N8560-64C N8560-32C N8560-48BC N5860-48SC
Ports 128x 10G/25G, 64x 40G, or 32x 100G 32x 100G, or 16x 100G, 4x 400G 64x 400G 64x 100G 32x 100G 48x 25G, 8x 100G 48x 10G, 8x 100G
Switch Chip BCM56870 BCM56980 BCM56990 BCM56970 BCM56870 BCM56873 BCM56873
Switching Capacity 6.4 Tbps 25.6 Tbps 51.2 Tbps 12.8 Tbps 6.4 Tbps 4 Tbps 2.56 Tbps
Forwarding Rate 4.76 Bpps 1.905 Bpps 10.3 Bpps 4.288 Bpps 2.98 Bpps 1.929 Bpps 1.920 Mpps
Virtualization Technology MLAG, Stack, EVPN-VXLAN MLAG / MLAG, Stack MLAG, Stack, EVPN-VXLAN MLAG, Stack, EVPN-VXLAN MLAG, Stack, EVPN-VXLAN
Latency <1μs <1μs <1μs <1μs <1μs <1μs <1μs
Max Power Consumption <650W <1950W <2524W <600W <450W <300W <300W

You might be interested in