To deal with the strong demands of utilizing faster media, mounting bandwidth and play "traffic cop” to an ever-growing network infrastructure, there occurred Fast Ethernet and Gigabit Ethernet successively. And it is of great importance for network designers to understand basics of Ethernet technologies to manage networks. This article will touch on Fast Ethernet technology, mainly describing its two types of transmission media: copper and fiber optics.

In computer networking, Fast Ethernet is a collective term for a number of Ethernet standards that carry traffic at the nominal rate of 100 Mbit/s (the original Ethernet speed was 10 Mbit/s). It was introduced in 1995 as the IEEE 802.3u standard and remained the fastest version of Ethernet for three years before it was superseded by the Gigabit Ethernet.

Just as its name shows, Fast Ethernet is an extension of the existing Ethernet standard. It is sometimes referred to as 100BASE-X, where "X" is a placeholder for the FX and TX variants. The "100" in the media type designation refers to the transmission speed of 100 Mbit/s, while the "BASE” refers to baseband signaling. The letter following the dash ("T” or "F”) refers to the physical medium that carries the signal (twisted-pair cable or fiber, respectively), while the last character ("X", "4", etc.) refers to the used encoding method., such as 100BASE-T and 100BASE-FX. That is to say, Fast Ethernet runs on unshielded twisted-pair (UTP) cables or optical fiber cables.

100BASE-T—Of all the copper-based Fast Ethernet standards, 100BASE-T is one of the most-commonly used standard and is specified for twisted-pair cables with link lengths up to 100 m (328 ft). Almost all 100BASE-T installations are 100BASE-TX.

100BASE-TX—100BASE-TX is the predominant form of Fast Ethernet. It uses CAT5-rated twisted-pair copper cable to connect various hubs, switches and end-nodes. It also uses an RJ45 jack just like 10BASE-T.

There are also 100BASE-T4 and 100BASE-T2 standardized for copper SFPs (small form-factor pluggable) to operate on UTP.

Fast Ethernet optical standards also include 100BASE-LX10 and 100BASE-BX, which are designed to run over single-mode fibers (SMF).

Fast Ethernet broke through the speed limit from 10 megabits per second to 100Mbps, and tackled the strong demand for high transmission speeds. Fiberstore supplies both 100BASE copper SFPs and optical SFPs for Fast Ethernet transmission, such as 100BASE-FX SFP (Cisco GLC-FE-100FX also included), 100BASE-LX10 SFP, 100BASE-EX SFP, etc. You can visit Fiberstore for more information about 100BASE SFPs for Fast Ethernet transmission.

Posted by: fernxu123 at 04:17 AM | No Comments | Add Comment
Post contains 557 words, total size 5 kb.

With the widespread recognition of Cisco optical products, such as Cisco switches and routers, Cisco GBIC transceivers and Small Form-Factor Pluggable (SFP) transceivers for telecommunications applications have gained more and more popularity and reputation in the market. When customers choose Cisco optical transceivers, what do you require besides basic specification? Have you encountered SFPs with or without digital diagnostic monitoring (DDM) interface, such as 1000BASE-SX SFP (eg. Cisco GLC-SX-MM or Cisco GLC-SX-MMD)? What is DDM? What can it be used for?

Digital diagnostic monitoring is also known as diagnostic optical monitoring (DOM). The diagnostic monitoring interface outlined in the SFF-8472 MSA (Multi-Source Agreement) is an extension of the serial ID interface defined in the GBIC specification, as well as in the SFP MSA. Nowadays, many modern optical SFP transceivers are designed to support digital diagnostics monitoring functions according to the industry standard MSA SFF-8472.

Actually, when customers buy Cisco optical transceivers, it is highly possible to have a dilemma between SFP with DDM or SFP without DDM. On March 8, 2013, Cisco announced the end of sale of its SFP transceiver Cisco GLC-SX-MM transceiver and published a replacement—Cisco GLC-SX-MMD transceiver. "D” in Cisco GLC-SX-MMD here just means the DDM function which is not designed in Cisco GLC-SX-MM. The following image is a product: NEW Cisco GLC-SX-MMD Compatible 1000BASE-SX SFP 850nm 550m EXT DDM Transceiver Module.

Don't just judge DDM functions from its name. Certainly, DDM interface allows for component monitoring on transceiver applications in great details. Additionally, DDM interface includes a system of alarm and warning flags which alert the host system when particular operating parameters are not in line with the normal operating parameters set by the factory. Consequently, users can find fault isolation according to outcomes of DDM, and predict failure possibilities and prevent such fault.

• Real-time digital diagnostic sensors—Via the two wire serial interface, the end user can access real-time internal measurements of the transceiver temperature, supply voltage, transmitter bias current, transmitter output power, and received optical power.

• Alarm and Warning thresholds —Corresponding high alarm, low alarm, high warning and low warning thresholds are defined in SFF-8472. The threshold values, which are typically defined by the vendor and factory preset, allow the user to determine whether or not the transceiver is operating outside target limits for desired performance.

An optional set of alarm and warning flags is also defined. When the alarm and warning feature is enabled, the transceiver, in addition to cyclically performing internal measurements of the diagnostic read-back parameters and digitally storing on memory, also checks how these read-back values compare with programmed alarm/warning threshold values.

By continually polling the alarm and warning flag bytes via its system software, the user has the power to better screen transceiver performance, so as to avoid the occurrence of link failures and potential system downtime.

Optical transceivers with DDM/DOM interfaces give the end user the ability to monitor parameters of the SFP, such as optical output power, optical input power, temperature, laser bias current, and transceiver supply voltage, in real time. This partly explains why Cisco GLC-SX-MMD replaced Cisco GLC-SX-MM. Although it is not designed with DDM function, GLC-SX-MM is still used by many users since it performs the similar functions as GLC-SX-MMD and costs less. Fiberstore supplies optical transceivers with DDM and without DDM to satisfy customers' different needs. Please feel free to contact us and visit Fiberstore for more information.

Article Resource:

https://www.fs.com/blog/digital-diagnostic-monitoring-introduction.html

Posted by: fernxu123 at 04:25 AM | No Comments | Add Comment
Post contains 586 words, total size 5 kb.

Many papers and articles have been contributed to the comparison between copper cabling and fiber cabling. Admittedly, fiber optic cabling have advantages over copper lines in terms of speed, capacity, bandwidth, etc. But this article will touch on another topic about copper-based Ethernet: 1000BASE-T vs. 1000BASE-TX.

The 1000BASE designation is an IEEE shorthand identifier. The "1000” in the media type designation refers to the transmission speed of 1000 Mbps. The "BASE” refers to base-band signaling, which means that only Ethernet signals are carried on the medium. The physical layer standard available for 1000 Gigabit Ethernet is twisted-pair cables (1000BASE-T). Before a deep discussion about comparison between 1000BASE-T and 1000BASE-TX is going on, the respective introduction to these two standards is included.

1000BASE-T (also known as IEEE 802.3ab) is a standard for Gigabit Ethernet over copper wiring. It uses four pairs of Category 5 unshielded twisted pair to achieve the Gigabit data rate. Each 1000BASE-T network segment can be a maximum length of 100m (330 feet). Typical applications of 1000BASE-T involve server witching in data centers, uplinks from desk computer switches. Or it is used directly to the desktop for broadband applications. Nowadays, 1000BASE-T modules are still widely used for Gigabit Ethernet transmission. For example, Fiberstore’s compatible Cisco 1000BASE-T Copper RJ45 (SFP-GE-T) operates on standard Category 5 unshielded twisted-pair copper cabling with link lengths up to 100 m, and supports LAN 1000Base-T Fibre Channel, switch to switch interface, server interface, and so on.

1000BASE-TX, also known as TIA/EIA-854, was a standard created and promoted by the Telecommunications Industry Association (TIA). This standard is similar to 1000BASE-T, but uses two pairs of wires for data transmission: one for sending data at speeds of 500Mbps, and the other for receiving data at comparable speeds on Category 6 or 7 cables. Though the simplified design of 1000BASE -TX has, in theory, reduced the cost of the required electronics by two pairs of wires, actually, this 1000BASE-TX solution has not been widely recognized because of the high costs of the required Category 6 and 7 cables and the falling price of 1000BASE-T products.

First, let's begin with their designs to differ the two standards. The 1000Base-T configuration adds a significant amount of complexity because of the bi-directional transmission (two-way transmission on a single pair). This design requires the use of hybrids to separate the transmission path from the receive path.It also requires high-powered digital signal processors (DSPs) to cancel the echoes generated by the near and far-end hybrids. By contrast, the design of 1000BASE-TX is simpler, requiring no hybrids, nor echo cancellation.

Second, difference lies in their transmission aspects. Each employs a different transmission technique and bit rate. 802.3ab (1000Base-T) calls for a 250 Mbits/sec bit rate, applied bi-directionally on each of the four pairs, in full duplex, while TIA/EIA-854 (1000Base-TX) calls for a 500 Mbits/sec bit rate, applied unidirectionally on each pair, so that the transmit path is physically separated from the receive path.

Last, the difference falls on cost. Just as what has been discussed above, the design of 1000Base-TX does not require hybrids, but its requirements for electronics and Category 6 and 7 cables are more expensive than 1000BASE-T configuration requirements.

After discussion, you may already have a choice in your mind as which one is better to be deployed according to budget and application of your project. As for 1000BASE-T SFPs, Fiberstore supplies 100% compatible copper SFP modules for your copper Ethernet. Besides Cisco SFP-GE-T, HP JD089B can also be found in Fiberstore. Of course, Fiberstore 1000BASE-T Auto Negotiation 1000BASE-TRJ45 Copper SFPs are also in large stock. You can visit Fiberstore to find a suitable 1000BASE-T SFP module for your copper network.

Posted by: fernxu123 at 03:46 AM | No Comments | Add Comment
Post contains 620 words, total size 5 kb.

Cisco Coarse Wave Division Multiplexing (CWDM) solution has made scalable and easy-to-deploy Gigabit Ethernet and Fibre Channel services possible in their networks. This solution mainly combines several different CWDM SFPs (small form-factor pluggable) and a set of CWDM passive multiplexers/demultiplexers or OADMs (optical add-drop multiplexers) to enable flexible network services. This kind of solution is a convenient and cost-effective one.

Before we gain a better understanding of CWDM SFP solution, we can have a look at CWDM SFPs first, an important component in this solution.

A CWDM SFP is a small form factor pluggable module for bi-directional serial optical data communications, and used as a part of CWDM optical network to provide high-capacity bandwidth across an optical fiber network. It is a hot-swappable transceiver component that is used to connect fiber cables and switches. It is designed for single-mode fibers and operates at a nominal wavelength of CWDM wavelength. The image below shows the outlook of CWDM SFP.

Now, let’s return to point CWDM SFP solution. The following passages mainly discuss three advantages of Cisco CWDM SFP solution.

Cisco CWDM solution is scalable, meaning that multiple channels can be provided as data demands increase. The scalability of CWDM SFP solution enables the transmission of up to eight channels over single-mode fibers. Besides, CWDM SFP transceivers are hot-swappable and they can be easily installed. What’s more, the devices contained in CWDM SFP solution are passive and require no power. Various network configurations ranging from multi-channel point-to-point to hub and meshed-ring configurations make this scalable CWDM SFP solution desirable for designers in telecommunication industry.

The components of Cisco CWDM SFP solution offer in Fiberstore are reliable and become a preferred choice for designers to avoid deployment failure incurred by other devices with low quality, thus saving money. In addition, while allowing enterprises and service providers to increase the bandwidth of an existing Gigabit Ethernet optical infrastructure, CWDM SFP solution doesn’t need to add any additional fibers. This solution can also be used in conjunction with other Cisco SFP devices on the same platform. In this way, investment can be protected.

Cisco CWDM SFP solution takes advantage of a multi-channel architecture and the inherent protection of ring architectures. At the channel endpoints, layer redundancy and failover mechanisms are used to allow designers to build highly available links. Additionally, in a ring architecture, the two-path link configurations are used to provide protection from fiber cuts.

Cisco CWDM SFP solution offers functionality in increasing network capacities and data transmission speed. Fiberstore, as a third party, offers CWDM SFP solution components, like CWDM multiplexers/demultiplexers, OADM, and CWDM SFPs. Besides CWDM SFPs, other Cisco compatible SFPs are also supplied, such as Cisco GLC-SX-MM and Cisco GLC-SX-MMD. You can see GLC-SX-MM price at Fiberstore.

Related Article:

http://www.cisco.com/c/en/us/products/collateral/interfaces-modules/cwdm-transceiver-modules/product_data_sheet09186a00801a557c.html

Posted by: fernxu123 at 07:22 AM | No Comments | Add Comment
Post contains 483 words, total size 4 kb.

There are numerous different types of fiber optical transceivers available in telecommunication market that can be used for various applications. When you choose fiber optic transceivers for your fiber networks, do you know how they work? What are their specific applications? This article mainly contributes to answering those two questions.

Before we discuss the two important aspects, it’s necessary to know the structure of a fiber optical transceiver, so that a better understanding of its working principle can be obtained.

Just as its name show, a fiber optic transceiver contains a fiber optic transmitter and a fiber optic receiver in a single module. There are four types of source for the transmitter that can convert the electrical signals into optical signals.: LEDs(light emitting diode), fabry-perot (FP) lasers, distributed feedback (DFB) lasers and vertical cavity surface-emitting lasers (VCSELs). They are tiny semiconductor chips. In a fiber optic receiver, semiconductor detectors (photodiodes or photodetectors) are used to convert optical signals to electrical signals.

A fiber-optic transceiver is known for receiving information from one end of the optical fiber and sending it through another fiber. The transmitter and the receiver are arranged in parallel in a fiber optic transceiver, so they can operate independently. And both the receiver and the transmitter have their own circuitry and can handle transmissions in both directions. In the fiber optics, information is sent in the form of pulses of the light. The light pulses have to be converted into electrical ones in order to be utilized by an electronic device. This process is done by the fiber optic receiver. In its fiber optic data links, the transmitter converts an electrical signal into an optical signal, which is coupled with a connector and transmitted through a fiber optic cable. The light from the end of the cable is coupled to a receiver, where a detector converts the light back into an electrical signal.

Fiber optic transceivers are utilized in various applications. Networking applications and radio applications are the most common places that they are deployed. Other target applications include FTTH (fiber to the home), Base Station (3G SFP CPRI/ 6G SFP+ CPRI), Fibre Channel (4G SFP/ 8G SFP+) and Ethernet systems (from 100Mbps to 10Gbps with different form factor / SFF, SFP, XFP and SFP+).

Fiberstore supplies a full range of fiber optical transceivers, such as SFP+ (SFP Plus) transceiver, X2 transceiver, and XFP transceiver. All our fiber transceivers are 100% compatible with major brands, including Cisco, like GLC-SX-MMD Cisco and Cisco GLC-SX-MM-RGD. Customized optical transceivers can also be offered by Fiberstore. You can visit Fiberstore for more information about optical transceivers to meet your needs.

Reference:

https://en.wikipedia.org/wiki/Fiber-optic_communication

Posted by: fernxu123 at 08:43 AM | No Comments | Add Comment
Post contains 465 words, total size 4 kb.

In the telecommunication industry, pulses of light are transmitted at high speed and with great accuracy in Gigabit Ethernet by using various optical products, including optical transceivers. There are numerous different form factors and optics types available in telecommunication market, such as XFP, GBIC, SFP/SFP+, or other transceivers. Are you confused by them? The following passages will provide information about these three standards for optical transceivers.

The XFP (10 Gigabit Small Form Factor Pluggable) is a standard for transceivers for high-speed computer network and telecommunication links that use optical fiber. It is the first small form factor 10GbE optics, not dependent on protocol. The specifications of XPF were developed by the XFP Multi Source Agreement (MSA) Group. Generally, it operates at optical wavelengths of 850nm, 1310nm or 1550nm. Fiberstore’s Cisco XFP10GLR-192SR-L is suitable for 10 GbE datacom (belly-to-belly for high density applications) and storage area network (SAN/NAS) applications based on the IEEE 802.3ae and Fibre Channel standards. Here is the picture of this product.

A GBIC (gigabit interface converter) is typically used in gigabit Ethernet and Fibre Channels. By offering a standard, hot swappable electrical interface, one gigabit port can support a wide range of physical media, from copper to long-wave single-mode optical fiber, at lengths of hundreds of kilometers. As a standard for transceivers, it is non-proprietary and defined by the Small Form Factor Committee in document number 8053i. Moreover, its flexibility makes it attractive in networking equipment, as it is opposed to fixed physical interface configurations.

As a variation of the GBIC, also known as mini-GBIC, the small form-factor pluggable transceiver (SFP) is a compact, hot-swappable transceiver. It interfaces a network device motherboard (for a switch, router, media converter or similar device) to a fiber optic or copper networking cable, applicable to Fast Ethernet of Gigabit Ethernet applications. SFP+ can be referred to as an expansion of the SFP standard. It is a 10GbE optics using the same physical form factor as a gigabit SFP.

XFP and SFP/SFP+ transceivers are both 10G optical modules, and share the same features with other 10G transceivers. The main difference lies in their sizes. That is SFP+ is more compact sized than XFP. What’s more, SFP+ complies with IEEE802.3, SFF-8431, SFF-8432, while XFP conforms to XFP MSA.

GBIC transceivers came into existence earlier than SFPs. In addition to the differences in application fields mentioned in above paragraphs, their sizes also differ from each other. The bigger size of GBIC makes it not feasible to provide more number of interfaces on a line card or a switch since it occupies more space. In other words, SFP is half the volume of GBIC and can be configured double number of ports on the same panel. Besides these differences, actually, GBIC and SFP/SFP+ transceivers share almost the same functions.

Fiber optic transceiver modules, designed and built with industry standards, become the core devices in fast Gigabit Ethernet transmission. Fiberstore supplies a wide range of optical transceivers. Besides XFP, GBIC, SFP/SFP+ transceivers, XENPAK transceiver, CWDM/DWDM transceiver, 40G QSFP+ & CFP can all be found in Fiberstore. Certainly, the type Cisco X2-10GB-LRM is also available in Fiberstore. You can visit Fiberstore for more information about fiber optical transceivers.

Related Article:

http://www.fs.com/introduction-to-small-form-factor-pluggable-sfp-transceiver-modules-aid-22.html

Posted by: fernxu123 at 06:59 AM | No Comments | Add Comment
Post contains 551 words, total size 5 kb.

The 10GBASE series optical transceiver modules are designed for 10 Gigabit Ethernet connectivity applications, enabling users to take advantage of 10-GbE connectivity. They are compatible with HP, applicable for 10 Gigabit Ethernet switch, router and other networking equipment from HP networking. These HP 1OGBASE transceiver modules are available in two most common packages: SFP+, XFP.

HP 10GBase SFP+ transceivers include: JD092B-C, JD093B-C, JD094B-C, J9150A-C, J9151A-C, J9152A-C; HP 10GBase XFP Transceiver include: JD117B-C, JD108B-C, JD088A-C, JD121A-C, JD107A-C. The following passages will mainly talk about the type JD094B compatible 10GBASE-LR SFP+ transceiver and the type JD117B 10GBASE-SR XFP transceiver.

SFP+ optical transceiver for JD094B 10GBASE-LR (Long Reach) operates at a wavelength of 1310nm over single-mode fibers, with a maximum link length at 10 km. It supports 10-Gigabit communications, suitable for telecommunications and enterprises which require 10GBASE long-distance fiber extension. Fiberstore’s JD094B offers high performance and a low cost. It is fully compliant with the SFP+ Multi-Sourcing Agreement (MSA). This kind of transceiver boasts of hot plug capability, designed with digital diagnostic function. The figure below is a Fiberstore’s JD094B compatible 10GBASE-LR SFP+ transceiver module.

This optical transceiver module is for transmission at a wavelength of 850nm over multi-mode fibers. It meets Ethernet standards, which makes it ideal for 10G data communications and storage area network applications. A variety of 10 Gigabit Ethernet connectivity options are given by this transceiver for data center, enterprise wiring closet, and switch-to-switch applications. Fiberstore’s new JD117B comprises a transmitter with a vertical cavity surface emitting laser (VCSEL) and a receiver with a PIN photodiode. Transmitter and receiver are separate within a wide temperature range and offer optimum heat dissipation and excellent electromagnetic shielding, thus enabling high port densities for 10 GbE systems. The picture below just shows an outlook of this optical module.

Actually, many manufacturers of fiber optics, including Cisco and Juniper, buy original equipment manufacturers’ optical transceivers and label these products on their own brands. Fiberstore supplies you with these compatible optical modules with high quality at a low price. Buy Fiberstore’s compatible products, you can get the considerate services and technical support. What’s more, these compatible SFP and XFP transceiver modules are backed by a lifetime warranty.

Fiberstore has a large selection of compatible 10GBASE SFP+/XFP modules in stock. Besides JD094B, JD117B, JD108B can also be found in Fiberstore. In addition, transceivers can be customized to meet your specific needs. You can visit www.fs.com for more information about compatible HP 10GBASE SFP+/XFP transceiver modules.

Related Article:

http://www8.hp.com/h20195/V2/getpdf.aspx/c04155377.pdf?ver=3

Posted by: fernxu123 at 07:04 AM | No Comments | Add Comment
Post contains 438 words, total size 4 kb.

SFP+ transceiver is a compact, hot-pluggable transceiver which is used for both telecommunication and data communications applications. It is the enhanced version of SFP (small form-factor pluggable) transceiver. Since 10 Gigabit Ethernet has been launched years ago, various 10GBASE SFPs+ transceivers have been produced. This publication will mainly introduce the Cisco 10GBASE SFP+ modules.

The Cisco 10GBASE SFP+ transceiver modules are designed for use in 10 Gigabit Ethernet links over optical fibers, providing a wide variety of 10 Gigabit Ethernet connectivity options. Listed below are three types of Cisco 10GBASE SFP transceiver modules: Cisco SFP-10G-SR transceiver module, Cisco SFP-10G-LRM transceiver module and Cisco SFP-10G-ER transceiver module.

10GBASE-SR (Short Range) is a port type for multi-mode optical fibers and uses 850nm lasers. It is one of the mostly used types because of its cost-effectiveness. The Cisco 10GBASE-SR transceiver module supports a link length of 26m on standard Fiber Distributed Data Interface (FDDI)-grade multi-mode fiber (MMF). Using 2000MHz*km MMF (OM3), long link lengths up to 300 m can be achieved. Using 4700MHz*km MMF (OM4), signals can be transmitted over a fiber with link lengths up to 400 m.

10GBASE-LRM (Long Reach Multi-mode) originally specified in IEEE 802.3aq is a kind of specification for multi-mode fibers and uses 1310nm lasers. The Cisco SFP-10G-LRM transceiver module supports link lengths of 220m on standard Fiber Distributed Data Interface (FDDI) grade multi-mode fiber (MMF). The image below shows the outlook of the SFP-10G-LRM transceiver module.

10GBASE-ER (Extended Reach) is a port type for single-mode fibers (SMF) and uses 1550nm lasers. The Cisco 10GBASE-ER module supports a link length of up to 40 kilometers on standard single-mode fiber (SMF, G.652). The following picture helps to have a better understanding of the 10GBASE-ER module.

The 10G SFP transceiver module is popular among its users due to its several features and benefits. Besides the above-mentioned long-distance transmission, this hot-swappable Cisco 10G SFP+ transceiver allows the flexibility of integrating the devices in the interfaces. In addition, this kind of SFP is compatible, and the replacement or repair process of optics is convenient. What’s more, the monitoring and diagnostics of optical fibers are easy because this transceiver module supports the digital optical monitoring. More information about Cisco 10GBASE SFP+ modules, please go to the following link:http://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/data_sheet_c78-455693.html

The Cisco 10GBASE SFP+ transceiver modules offer various computer connectivity options for data center, enterprise wiring closet, and service provider transport applications. In Fiberstore, you can find the above-mentioned 10GBASE SFPs. Bseides, Fiberstore SFP-10G-SR-X transceiver module is also available. If you have any further demand or question about 10GBASE SFPs, please visit Fiberstore with no hesitation.

Posted by: fernxu123 at 07:07 AM | No Comments | Add Comment
Post contains 458 words, total size 4 kb.