X2 evolved from the XENPAK standard, and its internal functional modules are basically the same as XENPAK. As we all know, XENPAK optical modules need to be slotted on the circuit board when they are installed on the circuit board, and high-density applications cannot be realized. The improved X2 optical module (its volume is only about half of XENPAK) can be directly placed on the circuit board, so it is suitable for high-density rack systems and PCI network card applications.
X2 modules offer customers a wide variety of 10 Gigabit Ethernet connectivity options for data center, enterprise wiring closet, and service provider transport applications.
Let's see what is the main features of 10GBASE X2 modules include:
10GBASE Ethernet supported
Has optical interoperability with respective 10GBASE Xenpak, 10GBASE XFP and 10GBASE SFP+ modules on the same link
Provides flexibility of interface choice
Hot-swappable input/output device plugs into an Ethernet X2 port of a Cisco switch or router to link the port with the network
Due to the continuous pursuit of size of optical modules, X2 has gradually disappeared from public view, but it is undeniable that it used to be an important role in the evolution of optical modules, and it also had glorious moments.