Switches are core devices in enterprise, industrial, and data center networks. They forward electrical or optical signals and establish dedicated communication links between any two network nodes, ensuring efficient data transmission. In local area networks (LANs) with multiple devices, switches are indispensable infrastructure.

Given their critical role, switches feature a variety of interfaces. This article provides a comprehensive overview of the most common switch interfaces, their features, and their typical applications.

01.RJ-45 Interface: Standard Ethernet Port

The RJ-45 interface is the most widely used network port, also known as a twisted-pair connector or 8P8C connector. It supports 10/100/1000Mbps Ethernet connections and is the primary port for office and industrial networks.

Key Features:

• 8P8C design with latch to prevent disconnection

• Compatible with Cat5e, Cat6, and other twisted-pair cables

• For Gigabit Ethernet (1000Base-T), at least Cat5e is required; Cat6 is recommended for stable high-speed transmission

• Widely used in enterprise networks, campus networks, and industrial Ethernet

RJ-45 ports are cost-effective, easy to deploy, and the most common choice for enterprise networks.

02.SC Fiber Interface: High-Speed Long-Distance Transmission

SC interfaces are mainly used in fiber switches and high-performance routers, suitable for long-distance, high-bandwidth connections. They are widely deployed in enterprise campus networks, data centers, and industrial networks.

Key Features:

• Square-shaped connector for easy plugging

• High immunity to electromagnetic interference

• Supports Gigabit and 10-Gigabit fiber networks

With the widespread adoption of Gigabit and 10-Gigabit networks, SC fiber interfaces remain common in high-end switches and backbone networks.

03.AUI Interface: Legacy Ethernet Port

AUI (Attachment Unit Interface) was used in early Ethernet to connect thick coaxial cables, commonly seen in token ring or bus-topology networks.

Key Features:

• D-sub 15-pin connector

• Can be converted to 10Base-T Ethernet via an AUI-to-RJ45 transceiver

• Largely obsolete, but may appear in legacy network systems

Today, AUI ports are rarely used in modern enterprise networks.

04 .FDDI Interface: Fiber Distributed Data Interface

FDDI (Fiber Distributed Data Interface) was an early high-speed fiber LAN technology, offering up to 100Mbps data transmission. It was commonly used in campus networks and enterprise backbone networks.

Key Features:

• Dual-ring token mechanism ensures network reliability

• Fiber-optic transmission with strong interference resistance

• Supports multiple topologies, including ring and star

With the rise of Gigabit and 10-Gigabit fiber, FDDI ports are gradually being replaced but may still exist in some backbone networks.

05 .Console Interface: Management Port for Switches

Console ports are essential for managed switches, enabling local configuration, troubleshooting, and maintenance.

Common Forms:

• RJ-45 Console

• Micro-USB Console

• USB Type-C Console (on newer devices)

Applications:

• Initial device configuration

• Network troubleshooting

• System recovery

• Local network management

In large enterprises or industrial networks, the Console port is a critical tool for network administrators.

Conclusion: Choosing the Right Switch Interfaces for Enterprise Networks

Switch interfaces vary in application:

• RJ-45: Standard Ethernet port, suitable for office and industrial networks

• SC Fiber: Ideal for long-distance, high-speed backbone networks

• AUI: Legacy interface, largely historical

• FDDI: Fiber backbone interface, gradually replaced by Gigabit fiber

• Console: Essential for managed switch configuration and maintenance

Understanding switch interfaces helps enterprises design effective network architectures, the right switches, and improve deployment and maintenance efficiency.