PAM4 Auto-Neg & Link Training

Autonegotiation is a tried-and-tested process where a device is connected to a network through an Ethernet interface, and the end points of a link share information on various capabilities relevant for the communication.

Autonegotiation determines the highest common denominator among the end-point capabilities, and these will be used for the communication. Link Training is another process that can take place when a device is connected to a high-speed Ethernet port through a copper cable or backplane. In this case it is important that the characteristics of the transmitted signal are tuned to be optimally carried over the copper cable.

Xena’s 7-speed dual-media test module Thor-400G-7S-1P supports the new PAM4-based 400GE, 200GE, 100GE and 50GE speeds defined in the IEEE 802.3bs and 802.3cd standards. It also has the unique advantage of also being able to test the NRZ-based speeds: 100GE, 50GE, 40GE, 25GE and 10GE. Installed in a ValkyrieBay or ValkyrieCompact chassis, it provides advanced Ethernet test capabilities up to Layer 3.

Learn more about troubleshooting Auto-negotiation and Link Training for the new PAM4-based 400GE 200GE, 100GE and 50GE data rates using Xena’s Thor-400G-7S-1P & Teledyne LeCroy’s SierraNet protocol analyzer.