"How to Select an Automotive Ethernet SWITCHES" Guide

This article will explain the following important points when selecting an automotive Ethernet system.

Basic specs to check
Ensuring communication quality and real-time performance
Security and Redundancy

Please refer to this if you are unsure about which functions to choose, what aspects to consider, and what parts to select.

Introduction: Why SWITCHES Selection is Important

In recent years, in-vehicle networks have evolved rapidly. There has been a shift from conventional communication methods such as CAN and LIN to faster, higher-bandwidth Ethernet-based communication. In particular, the amount of data handled within vehicles has increased several-fold due to advances in ADAS (Advanced Driver Assistance Systems), autonomous driving, and infotainment.
In this context, Ethernet SWITCHES are no longer simply "communication repeaters," but play a central role in ensuring the reliability, real-time performance, and security of the entire in-vehicle system.

Choosing the wrong SWITCHES can lead to the following problems:

Control system instability due to communication delays and packet loss
Risk of external attacks due to security vulnerabilities

This article explains the technical and practical points to keep in mind when selecting an automotive Ethernet SWITCHES, incorporating knowledge gained from actual development work.

Basic specs to check

When selecting an in-vehicle Ethernet SWITCHES, first check its basic specifications, which are important for determining whether SWITCHES is compatible with the vehicle architecture and applications.

Number of ports and configuration

Select the number of ports required depending on the number of ECUs, sensors, and cameras to be connected.
Typical SWITCHES have 4 to 16 ports, but the optimal number of ports varies depending on the system.
Let's clarify the number of ports required for each communication standard and their breakdown.

Supported communication standards

The communication standards supported by an Ethernet SWITCHES are crucial for meeting the communication requirements of each vehicle. Selecting the appropriate standard will improve the stability and performance of the entire system.
The main specifications are as follows:

100BASE-T1: Medium speed. For sensor data and control systems.
1000BASE-T1: Medium to high speed. For camera footage and infotainment.
10BASE-T1S: For transmitting low-speed sensor data.

When selecting an Ethernet SWITCHES, be sure to check the PHY (physical layer device) and connection method (SGMII, RGMII, RMII, etc.) to ensure design compatibility and scalability.

Please check the details on our website below.

Ensuring communication quality and real-time performance

When selecting an in-vehicle Ethernet SWITCHES, ensuring communication quality and real-time performance is extremely important. In particular, in ADAS, autonomous driving, and vehicle control systems, communication delays and unstable networks directly affect safety and control accuracy, so stable communication with little delay is required.

TSN (Time-Sensitive Networking) compatible

TSN is a group of technologies that adds real-time capabilities to Ethernet communications. Selecting a TSN-compatible SWITCHES can achieve high reliability and real-time capabilities in an in-vehicle network. The main TSN functions are as follows:

802.1Qbv (scheduling)
→ Controls communication schedules and ensures transmission of high-priority communications.

802.1AS (time synchronization)
→ Achieve time synchronization across the entire network, enabling consistency of control signals and cooperative operation between multiple ECUs.

802.1Qbu (FRAMES preemption)
→ Even in the middle of a long FRAMES, control signals with high urgency can be inserted and transmitted.

Please check the details on our website below.

What is TSN?

Security and Redundancy

In-vehicle networks are communications environments where safety and reliability are of paramount importance. When selecting an Ethernet SWITCHES, ensuring security and redundancy is essential. With the increasing use of external connections, over-the-air (OTA) updates, and V2X communications, it is becoming increasingly important to be prepared for unauthorized Access and communication interruptions.

Security Features

MACsec (IEEE 802.1AE)

MACsec is a technology that encrypts communications to prevent tampering and eavesdropping. In automotive applications, it is used in the following situations:

Strengthened security when communicating with external parties via a gateway
Protection of confidential data between ECUs (logs, diagnostic information, etc.)
Ensuring data integrity during OTA (Over The Air) updates

Selecting a MACsec-compatible SWITCHES enables security measures at the hardware level.

Please check the details on our website below.

MACsec and encryption

ACL (Access Control List)

ACL is a feature that controls communication through SWITCHES based on rules. The following settings are available:

Allow or deny communication from specific MAC addresses or IP addresses
Port-based communication restrictions
Protocol-based FILTERS

By utilizing ACLs, you can block unauthorized Access and unnecessary communications, and flexibly implement security policies.

Please check the details on our website below.

What is ACL?

802.1CB (Seamless Redundancy)

802.1CB is a technology that allows the same data to be sent simultaneously over multiple routes, so that communication can continue automatically over an alternative route even if communication is interrupted. It is used for the following purposes:

Improving the reliability of communications for autonomous driving control systems
Stabilization of video data from camera sensors
Redundancy of gateways and backbone communications

Selecting an 802.1CB compatible SWITCHES enables a fail-safe design, improving vehicle safety and reliability.

Please check the details on our website below.

What is IEEE802.1CB?

Summary: Choosing the Right Automotive Ethernet SWITCHES

When selecting an in-vehicle Ethernet SWITCHES, it is important to make a comprehensive judgment from various perspectives, including communication quality, security, designability, and evaluation ability. In particular, with the advancement of ADAS and autonomous driving, in-vehicle communications are becoming more complex and sophisticated.
In this article, we have organized points to check when selecting a system, not only from the perspective of technical specifications but also from the perspective of practical use in actual development sites, such as implementation, evaluation, and diagnosis.
We hope that this information will help you select the optimal Ethernet SWITCHES and ensure the smooth progress of your project in your product development and design considerations.