FAQs about 40G Ethernet Networking

With the development of fiber technology, the 10G/25G Ethernet transmission can no longer meet the needs of enterprises for larger capacity and higher speed data transmission. Undoubtedly, as more users opt to deploy 40G Ethernet for data center interconnectivity, 40G Ethernet is maturing and gaining popularity. So, what exactly is 40G Ethernet? What are its key benefits? Here are some answers to frequently asked questions (FAQs) about 40G Ethernet networking.

What Is a 40G Ethernet Networking?

The term 40G Ethernet stands for 40 gigabit Ethernet, which refers to a version of computer networking technology used to transmit data at a rate of 40 gigabits per second. By combining existing Ethernet technologies and interfaces with the new technology, achieving a higher achievable data transfer speed is possible. There are several ways 40G Ethernet shows its advantages over 10G and 25G Ethernet technologies. 40G Ethernet can deliver faster data transfer speeds, allowing access to files in corporate networks, and solving complex tasks in data centers will be less time-consuming.

In a 40G Ethernet network, commonly used connection methods include fiber optic connections and high-speed cable connections. Fiber optic connections utilize optical modules and fiber optic cables to transmit data, offering longer transmission distances and higher bandwidth. High-speed cable connections, on the other hand, transmit data to the target devices through specialized high-speed cables.

What Are the Applications of 40G Ethernet Networking?

40G Ethernet is a perfect solution for long-haul transmission and switch-to-switch transmission. In addition, it will be suitable for large enterprises and data centers requiring high-bandwidth and low-latency transmission, especially for those with large virtualized virtual machines and container pools, to meet their customers’ needs.

The following scenarios can also be used with 40G Ethernet:

• An aggregation, routing, and switching system in a data center

• Exchange points in the network

• Peering points between service providers

• Applications for high-bandwidth networks

• Cloud computing or high-performance computing systems

In What Ways Will 40G Transmission Performances Be Influenced?

Several factors that can influence the process of implementing a 40G Ethernet network, such as bandwidth, insertion loss, and so on, could affect the implementation of this network.

Skew

Several parameters affect 40G Ethernet transmission, but one of the most important is skew. It should be noted that skew refers to the difference in time of flight between optical signals traveling over different fibers. Parallel optics and 40G Ethernet, which uses 40G Ethernet, are closely related to skew. A parallel optic system allows splitting one data stream into multiple data streams and transmitting them over multiple fibers, allowing low-cost transceivers to be used.

Bandwidth

Other essential factors limit the use of 40G Ethernet, including bandwidth. If the 40G Ethernet uses enough bandwidth, the transmission distance over OM3 and OM4 fibers allows companies to meet their users’ demands better.

Insertion loss

An inserted component, such as a connector or coupler, can cause total optical power loss, referred to as insertion loss. An air gap between matching ferrules or scratching and contamination can cause it. It is possible to improve the performance of 40G Ethernet significantly with a reduction in insertion loss.

Which Type of Connectors and Cabling Are Used in 40G Ethernet Networking?

Cable for 40 Gigabit Ethernet can be either optical fiber or copper. The supportable channel length depends on the cable and the transceiver type. For data centers that operate at 40 Gbps, OM3 and OM4 multimode cabling is generally recommended because its reach supports a wider range of deployment configurations compared to copper solutions. And the cost is lower compared to single-mode solutions. As for the connectors, the only significant change stipulated in the 802.3ba standard is the use of MPO (Multi-Fiber Push On) -type connectors at the multimode transceivers to support the multifiber parallel optics channels. Except for the MPO connectors mentioned above, there are also some 40G transceivers equipped with LC connectors that need to work together with LC patch cables.

What Are 40G Ethernet Networking Transceivers?

Transceivers for Ethernet 40G are being developed along several standard form factors. Generally speaking, there are four types of transceivers applied for 40G Ethernet—QSFP (Quad Small-Form-Factor Pluggable), QSFP+, CXP, and CFP, of which the mainstream is the QSFP+. The QSFP+ is an evolution of QSFP and it provides four transmit and four receive lanes to support 40 Gigabit Ethernet applications for multimode fiber and copper today. They may serve 40G Ethernet cables and connectors. As for CFP, its size is much larger than QSFP. It features 12 transmit and 12 receive 10Gbps lanes to support one 100 Gigabit Ethernet port, or up to three 40 Gigabit Ethernet ports. Its larger size is suitable for the needs of single-mode optics and can easily serve multimode optics or copper.

What Type of Transmission Method Is Used in 40G?

Parallel optical transmission is employed for 40G Ethernet over multimode fibers. There is a significant difference between parallel optical transmission and traditional serial transmission based on the parallel optical interface. Therefore, transmitting and receiving data simultaneously through multiple fibers is possible. There is also the option of achieving 40G Ethernet over single-mode fibers such as MTP or LC, which can be healthier and more suitable for high-density data centers.