QSFP vs QSFP-DD vs SFP vs LC vs MPO/MTP – Putting it all together

Transceiver Types

Quad Small Form-factor Pluggable Double Density (QSFPDD)

  • Definition: An evolution of the QSFP form factor, this transceiver can support eight channels of 50 Gigabit Ethernet, 200 Gigabit Ethernet, and 400 Gigabit Ethernet. It utilizes eight lanes that operate up to 25 Gbps NRZ modulation or 50 Gbps PAM4 modulation, potentially offering an aggregate of 200 Gbps or 400 Gbps respectively.
  • Use Cases: High-speed networking, including in data centers, high-performance computing centers, and enterprise core and distribution level applications.
  • Advantages:
    • High Data Rate: This can support extremely high data rates, making it suitable for modern networks demanding higher bandwidth.
    • Backward Compatibility: Compatible with existing QSFP modules, helping gradually upgrade networks.

Quad Small Form-factor Pluggable (QSFP)

  • Definition: QSFP transceivers are designed to accommodate Ethernet, Fibre Channel, InfiniBand, and SONET/SDH standards with different data rate options. QSFP transceivers are available with a variety of transmitter and receiver types.
  • Use Cases: Used widely in data centers, high-performance computing networks, and enterprise network environments for inter-rack and intra-rack transmission.
  • Advantages:
    • High Density: Allows for more port density than traditional SFP modules.
    • Flexible: Available in several types supporting a wide range of physical media from copper to long-wavelength single-mode optical fiber.

Small Form-factor Pluggable (SFP)

  • Definition: SFP transceivers are compact, hot-pluggable devices for telecommunication and data communications applications. They interface a network device motherboard (for a switch, router, media converter, or similar device) to a fiber optic or copper networking cable.
  • Use Cases: Commonly used in datacom and telecom networks, supporting applications such as Gigabit Ethernet, Fibre Channel, etc.
  • Advantages:
    • Versatility: Supports a wide range of data rates and standards.
    • Hot-Pluggable: Allows easy and quick swapping without powering down the network system.
    • Variety: Comes in various versions, including SFP+ (enhanced version with higher data rates) and SFP28 (for 25G and 50G networks).


All these pluggable form factors are pivotal in modern networking, offering different data rate options, compatibility with various media types, and hot-swappable capabilities for uninterrupted network operations. The choice depends on specific networking requirements, including desired data rates and transmission distances.

Connector Types

LC Connector

  • Definition: LC connectors are small form-factor connectors that feature a ferrule of 1.25mm diameter, making them compact enough to fit into dense patch panels. They are usually used with SFP and SFP+ transceivers.
  • Use Cases:
    • 1G/10G Networks: Commonly used in Gigabit and 10-Gigabit Ethernet networks.
    • Fiber Channel: Utilized in fiber channel connections.
  • Advantages:
    • High Density: Allows for high port density in patch panels due to its small size.
    • Simplex and Duplex: Available in simplex and duplex configurations, facilitating versatility in network setups.

MPO/MTP Connector

  • Definition: MPO (Multi-fiber Push On) and MTP (a branded version of MPO) connectors are designed to bundle multiple fibers, facilitating high-density connections that can be leveraged in high-speed data networks. They are usually used with multi-fiber cables and higher-speed QSFP and QSFPDD transceivers.
  • Use Cases:
    • 40G/100G/400G Networks: Commonly used in high-speed networks, including 40G, 100G, and 400G Ethernet connections.
    • Data Centers: Essential in data center environments where high-density connections are required.
  • Advantages:
    • High Bandwidth: Facilitates high bandwidth transmissions by bundling multiple fibers.
    • Quick Deployment: Allows for quick deployment and removal thanks to the push-pull tab design.


In conclusion, LC and MPO/MTP connectors are integral to modern data communications, offering solutions for various network speeds and environments. LC connectors are often favored for lower-speed networks due to their compact size and versatility. In contrast, MPO/MTP connectors find utility in high-speed, high-density network infrastructures, including modern data centers and high-performance computing setups. They are chosen based on the network’s specific requirements, including the transceivers in use and the desired data rates.


  • Transceiver types (like QSFPDD, QSFP, and SFP) refer to the design and form factor of the transceiver modules themselves. These transceivers can support various data rates and communication standards, and they are plugged into switches, routers, or other network devices to facilitate data transmission through fiber optic or copper cables.
  • Connector types (such as LC, MPO/MTP) refer to the connectors used at the ends of the fiber optic cables that plug into the transceivers. These connectors physically mate the cables to the transceivers, ensuring light (in the case of fiber optics) can pass through and carry data from one end to the other.

So, in a typical setup, you would have a transceiver plugged into a network device and a cable with connectors at both ends — one end connects to the transceiver, and the other end connects to another transceiver in a different network device, thus establishing a data link.

Choosing the correct combination of transceivers and connectors is essential to establishing a high-performance network, meeting the specific requirements of data rate, transmission distance, and other factors in different networking environments.

Common Combinations

Data Centers

  • QSFP28 transceivers with MPO/MTP connectors: This combination is typically used for 100G connections, leveraging the high bandwidth potential of multi-fiber connections.
  • QSFP-DD transceivers with MPO/MTP connectors: Increasingly popular in modern data centers, this is used for 400G connections, offering high bandwidth over a single cable.

Enterprise Networks

  • SFP+ transceivers with LC connectors: Commonly used for 10G connections in enterprise networks, offering good performance and reliability.
  • QSFP+ transceivers with MPO/MTP connectors: Employed for 40G connections, often in backbone networks to ensure high-speed connectivity within the enterprise.


  • SFP transceivers with LC connectors: Widely used for 1G and lower-speed connections, suitable for various applications including in telecommunications networks.

Campus Networks

  • SFP28 transceivers with LC connectors: Used for 25G connections, this combination is becoming more popular in campus networks, offering higher bandwidth than older 10G connections but without the higher costs associated with 100G infrastructure.

Future-Ready Installations

  • QSFP-DD or OSFP transceivers with MPO/MTP connectors: These combinations offer paths to extremely high data rates (up to 400G and potentially beyond) for organizations looking to future-proof their networks.

Cloud Service Providers

  • CFP/CFP2/CFP4 transceivers with LC or MPO/MTP connectors: These are utilized for very high-speed connections, commonly in the networks of cloud service providers.


In any case, it’s always important to carefully select the right combination of transceivers and connectors, considering not just the immediate needs of the network but also future scalability and upgrade paths. Different scenarios require different combinations to achieve the optimal balance of performance, cost, and future readiness.