Tag Archives: XENPAK

Factors to Consider for 10 GbE Network Deployment

Nowadays, 10 Gigabit Ethernet network has been very popular and been employed by large amount of enterprises in their corporate backbones, data centers, and server farms to support high-bandwidth applications. To achieve a reliable and cost-effective 10 Gigabit Ethernet network, here are several factors that you should take into consideration for the deployment.

More Cost-effective for SAN

Direct-attached storage, network attached storage and SAN are three types of storage in a network. Among them, SAN is the most flexible and scalable solution for data center and high-density applications. But SAN costs much and needs special training for the installation and maintainance of the Fibre Channel interconnect fabric. The internet small computer system interface (iSCSI), which allows 10GbE infrastructure to be used as a SAN fabric, makes 10 GbE an attractive interconnect fabric for SAN applications. Compared with Fibre Channel, 10GbE infrastructure is more favorable because it can reduce equipment and management costs, enhance server management, improve disaster recovery and deliver excellent performance.

More Efficient for the Server Edge

Many organizations try to optimize their data centers by seeking server virtualization, which can support several applications and operating systems on a single server by defining multiple virtual machines on the server. And this can help organizations to reduce server inventory, better utilize servers, and mange resources more efficiently. Server virtualization relies heavily on networking and storage. Virtual machines require lot of storage. The network connectivity between servers and storage must be fast enough to avoid bottlenecks. 10GbE can provide fast connectivity for virtualized environments.

Reducing Bottlenecks for the Aggregation Layer

Today, traffic at the edge of the network has increased dramatically. Gigabit Ethernet to the desktop has become more popular. Many people adopt Gigabit Ethernet to the desktop, increasing the oversubscription ratios of the rest of the network, which brings the bottleneck between large amounts of Gigabit traffic at the edge of the network and the aggregation layer or core. 10 GbE allows the aggregation layer to scale to meet the increasing demands of users and applications. It can well solve the bottleneck for its three advantages: 10 GbE link uses fewer fiber stands compared with Gigabit Ethernet aggregation, 10 GbE can support multi-gigabit streams and 10 GbE provides greater scalability, bringing a future-proof network.

Fiber Cabling Choices

To accomplish 10 GbE network deployment, three important factors should be considered, the type of fiber cable (MMF of MF), the type of 10 GbE physical interface and optics module (XENPAK, X2, XFP and SFP+). Form factor options are interoperable when 10 GbE physical interface type is the same on both ends of the fiber link. For example, 10GBASE-SR XFP on the left can be linked with one 10GBASE-SR SFP+ on the right. But 10GBASE-SR SFP+ can’t connect to one 10GBASE-LRM SFP+ at the other end of the link. And 10G SFP+ active optical cable, such as Cisco SFP-10G-AOC3M SFP+ active optical cable (as shown below) and Cisco SFP+ active optical cable, SFP-10G-AOC10M, is also a good choice.

Cisco SFP-10G-AOC3M Compatible 10G SFP+ Active Optical Cable

Copper Cabling Solutions

Other than fiber optic cabling solutions, there are also copper cabling solutions for 10GbE. Copper cabling solutions are suitable for short distance connections. There are three copper cabling solutions: 10GBASE-CX4, SFP+ direct attach copper cable and 10GBASE-T.

10GBASE-CX4 is the first 10 GbE standard. It’s economical and it allows very low latency, but it’s a too large form factor for high density port counts in aggregation switches. 10G SFP+ direct attach copper cable (10g copper SFP) is a popular copper solution for 10 Gigabit Ethernet, which has become the main choice for servers and storage devices in a rack for its low latency, small connector and reasonable cost. 10GBASE-T runs 10 GbE over Cat6a and Cat7 up to 100 m.

For Top of Rack Applications

A top-of-rack (ToR) switch is a switch with a low number of ports that sits at the very top or in the middle of a 19″ telco rack in data centers. A ToR switch provides a simple and low-cost way to easily add more capacity to a network. It connects several servers and other network components together in a single rack. ToR switch uses SFP+ to provide 10G network in an efficient 1U form factor. Each server and network storage device can be directly connected to the ToR switch, eliminating the need for intermediate patch panels. And the cabling outside the rack, the ToR switch uplink connection to the aggregation layer, simplifies moving racks. The figure below shows a 10GbE ToR switching solution for servers and network storage. Because the servers are virtualized, so the active-active server team can be distributed across two stacked witches, which can ensure physical redundancy for the servers while connected to the same logical switch. What’s more, failover protection can be offered if one physical link goes down.



10 Gigabit Ethernet network is not the fastest solution, but it is quite enough for common applications in our daily life. For a better and successful 10 Gigabit Ethernet network deployment, you need to take all those factors mentioned above into consideration. And it can also help you make better options about fiber or copper cabling solutions for your 10G networks.

Optical Transceivers for 10 Gigabit Ethernet

Just as 10 gigabit Ethernet (10GbE) technologies have changed, so have the cabling technologies that support them and the devices that connect the cabling to their network. Optical transceivers provide the interface between the equipment sending and receiving data and the cabling transporting it. Just as there are distinct cabling technologies that coincide with 10 gigabit technologies, various transceivers are also available to match each cabling standard. 10 gigabit Ethernet has mainly four defined optical transceiver types. These optical transceivers are the result of multi-source agreement (MSA) which enables vendors to produce 802.3ae-compliant pluggable transceivers. This post will give a brief introduction to these four types of transceivers—XENPAK, X2, XFP, and SFP+.


XENPAK, the first 10 gigabit Ethernet pluggable transceivers on the market to support the 802.3ae standard transmission optics. They are large, bulky and used mainly in LAN switches. These transceivers are “hot pluggable” and support the new 802.3ak copper standard with vendors now producing transceivers to connect CX4 cables. XENPAK is a highly integrated, serial optical transponder module for high-speed, 10Gbit/s data transmission and offers a wide variety of 10 gigabit Ethernet connectivity options for data center, enterprise wiring closet, and service provider transport applications. It is designed to transmit and receive optical data of link length of 300m, 10km, 20km, 40km, up to 80km. XENPAK 10GB solution include dual fiber XENPAK, CWDM XENPAK and DWDM XENPAK modules which enable high port densities for 10 gigabit Ethernet systems.


X2, the smaller brother of the XENPAK pluggable transceiver, is about 2/3 the size of the XENPAK transceiver module. With the same “hot pluggable” specifications and supporting all the 10 gigabit Ethernet standards (including copper), the X2 form factor allows for more port density on switches. X2 fiber optic transceiver module is used in datacom optical links only (not telecom). Its electrical interface to the host board is also standardized and is called XAUI (10 Gigabit attachment unit interface). X2 uses the same 70-pin electrical connector as XENPAK and supports implementations of XENPAK’s four lane XAUI at both Ethernet (3.125 Gbit/s) and/or Fiber Channel (3.1875 Gbit/s) rates. X2 will also support serial electrical interfaces as they may emerge in XENPAK, as well as ongoing maintenance. There are 300m, 10km, 20km, 40km, 80km X2 optical modules, like Cisco X2-10GB-SR, X2-10GB-ER and X2-10GB-ZR, which provides customers with a strong sense of assurance that this technology is a good choice and will have strong vendor support. The picture below shows a XENPAK transceiver and an X2 transceiver.



XFP modules are hot-swappable and protocol-independent. They typically operate at near-infrared wavelengths (colors) of 850 nm, 1310 nm or 1550 nm. Principal applications include 10 gigabit Ethernet, 10 Gbit/s Fibre Channel, synchronous optical networking (SONET) at OC-192 rates, synchronous optical networking STM-64, 10 Gbit/s optical transport network (OTN) OTU2, and parallel optics links. They can operate over a single wavelength or use dense wavelength-division multiplexing techniques. They include digital diagnostics that provide management added to the SFF-8472 standard. XFP modules use an LC fiber connector type to achieve higher density. The positive aspect of the XFP form factor is it will allow switch vendors to increase port density in a smaller area for cost savings. A drawback of the XFP will be its inability to support the current copper (802.3ak) or the 10GBASE-LX4 standards.


SFP+, the enhanced version of the SFP, supports data rates up to 16 Gbit/s. It is a popular industry format supported by many network component vendors. In comparison to earlier XENPAK or XFP modules, SFP+ modules leave more circuitry to be implemented on the host board instead of inside the module. Consideration has to be given to whether the module is linear or limiting. Linear SFP+ modules are most appropriate for 10GBASE-LRM; otherwise, limiting modules are preferred. SFP+ also introduces direct attach for connecting two SFP+ ports without dedicated transceivers. SFP+ supports 8 Gbit/s Fibre Channel, 10 Gigabit Ethernet and Optical Transport Network standard OTU2. Although the SFP+ standard does not include mention of 16G Fibre Channel, it can be used at this speed. The picture below shows an XFP transceiver and an SFP+ transceiver.

XFP and SFP+

Fiberstore is a professional manufacturer and supplier for good quality optical transceivers products. They offer these four kinds of optical transceiver modules for 10 gigabit Ethernet cabling applications. For example, Cisco XFP-10G-MM-SR, FTLX8512D3BCL XFP and FTLX8571D3BCL SFP+ branded by Finisar are for 10GBASE-SR; Cisco XFP-10GLR-OC192SR and HP 455886-B21 SFP+ are for 10GBASE-LR.