Multiplexers Used In Communication

A multiplexer, sometimes referred to a multiplexor or simply a mux, is an electronic device that selects from several input signals and transmits to one or more output signals, can be considered as a multiple-input, single-output switch. A Phone Optical Multiplexer is an example of a very large virtual multiplexer that is built from many smaller, discrete ones. An electronic multiplexer makes it possible for multiple signals to share one device or resource, for example, one A/D converter or one communication line, instead of having one device per input signal.

Multiplexers connect or control, multiple input lines called “channels” consisting of either 2, 4, 8 or 16 individual inputs, one at a time to an output. A multiplexer is often used with a complementary demultiplexer on the receiving end. A demultiplexer (or demux) is a single-input, multiple-output switch. At the receiving end, a demux, chooses the correct destination from the many possible destinations by applying the same principle in reverse.

Generally, multiplexers are used as one method of reducing the number of logic gates required in a circuit or when a single data line is required to carry two or more different digital signals. It selects one of many analog or digital input signals and forwards the selected input into a single line. A multiplexer of 2n inputs has n select lines, which are used to select which input line to send to the output.

Multiplexers also are used in building digital semiconductors such as central processing units (CPUs) and graphics controllers. In these applications, the number of inputs is generally a multiple of two, the number of outputs is either one or relatively small multiple of two, and the number of control signals is related to the combined number of inputs and outputs.

Types of multiplexers are used in communications. In its simplest form, a multiplexer will have two signal inputs, one control input and one output. One example of an analog multiplexer is the source control on a home stereo unit that allows the user to choose between the audio from a compact disc (CD) player, digital versatile disc (DVD) player and cable television line.

There are some more complex forms of multiplexers. Time-division multiplexers(or TDM), for example, have the same input/output characteristics as other multiplexers, but instead of having control signals, they alternate between all possible inputs at precise time intervals. Alternatively, a digital TDM multiplexer may combine a limited number of constant bit rate digital data streams into one data stream of a higher data rate, by forming data frames consisting of one timeslot per channel. Time-division multiplexers generally are built as semiconductor devices, or chips, but they also can be built as optical devices for fiber optic applications.

PDH Multiplexer designs for highly integrated structure and provides 16 standard E1 interfaces together with one channel of order wire, with self-contained alarm and NM functions, as well as self-testing and E1 loop-back testing functions. While, digital multiplexer is constructed from individual analogue switches encased in a single IC package as opposed to the “mechanical” type selectors such as normal conventional switches and relays.

The Optical Splitters for FTTX Applications

fiber splitter is a very important passive component that used in the optical network system to achieve the optical singles’ coupling, branching, and distributing, just the same with the coacial cable transmission system does. An optical splitter is fiber optical tandem device with multiple import or output terminals. Generally we often use M x N to indicate a splitter with M import and N output numbers. The optical splitters that used in the CATV system, are generally 1 x 2, 1 x 3 or the 1 x N fiber splitters that composed by them.

Fiber optic splitter is the passive components for FTTH PON (passive optical network). Gigabit Ethernet Passive Optical Network (GPON) splitters play an important role in Fiber to the Home (FTTH) networks by allowing a single PON network interface to be shared among many subscribers. Networks implementing BPON, GPON, EPON, 10G EPON, and 10G GPON technologies all use these simple optical splitters.

Every passive optical network, no matter GPON, EPON systems are comprised by the Optical Line Termination (OLT), the Optical Network Unit (ONU) and Optical Distribution Network (ODN). The ODN is the most important component is the FTTx systems which is the physical channel of the optical transmission between the OLT and ONU. It is composed by fiber optic cables, optical connectors, and most importantly, the fiber splitters as well as ancillary equipment connecting these devices.

 

There are two basic splitter technologies for the passive optical network: Fused Biconical Taper (FBT) and Planar Lightwave Circuit (PLC), which correspond with to types of fiber splitters, FBT splitter, also know as FBT coupler, and PLC splitter. Fused Biconical Taper is the older technology and generally introduces more loss than the newer PLC splitters.

The PLC Splitter contains no electronics and use no power. both PLC and FBT splitters are used in PON networks. A PON network may be designed with a single optical splitter, or it can have two or more splitters cascaded together. Since each optical connection will add the optical attenuation, a single splitter is superior to multiple cascaded splitters. One net additional coupling (and source of attenuation) is introduced in connecting two splitters together.

With the accessing network construction boom and the increasing subscribers trend in the market. PLC splitter will no double to become the main force in the market, the PLC optical splitters has the features of digitization, networking, broadband, miniaturization and easy maintenance, etc.

SFP Plus Transceiver With Newest Industrial Standard

SFP+ Transceivers (Small Form-Factor Pluggable) are the upgraded version of the former SFP transceivers (mini GBIC), with higher data rate and new industrial standards. It is smaller than any of the currently shipping form factors and provides the highest density per line card. SFP+ offers customers both immediate benefits and long-term advantages in supporting evolving data center needs. The SFP+ specification was first published on May 9, 2006, and version 4.1 published on July 6, 2009. It is a international industry format supported by many network component vendors.

SFP+ is an innovative, next-generation transceiver module. Initially, it is targeted to support speeds of 10 Gbps for next-generation Gigabit Ethernet applications and 8.5Gbps Fiber Channel systems. What is more, SFP plus is with lower power consumption for less than 1W and it is even cost effective. These transceivers are with managed digital optical monitoring and superior high temperature performance.

Several industrial acknowledged standards for SFP plus has been released for 10Gpbs networks, including 10Gbase-SR, which define the SFP plus transceiver working with OM3 10G multimode fiber at 30 to 300 meters range, 10Gbase-LR which define the SFP plus transceiver working with single mode fiber at 10km range, 10Gbase-LRM which define the FDDI multimode fiber at around 220 meters range.

Compare With XENPAK or XFP Modules
In comparison to earlier XENPAK or XFP modules, SFP+ module is with more compact size compared with the former 10G transceivers X2 and Xenpak, leave more circuitry to be implemented on the host board instead of inside the module.
The advantages of SFP+ modules:
SFP+ Has A More Compact Form Factor Package Than X2 And XFP.
It Can Connect With The Same Data Rate Of XFP, X2 And XENPAK Directly.
The Cost Of SFP+ Is Lower Than XFP, X2 And XENPAK.

SFP+ Transceiver is interchangeable with SFP transceiver and can be used in the same cages as SFP transceiver. For 10G applications, SFP+ transceiver has a smaller footprint and lower power consumption than XFP transceiver. The electrical interface to the host board for SFP transceiver and SFP+ transceiver is the same serial.

Many companies, such as Cisco, Finisar, and Sumitomo, have released SFP+ transceivers. SFP+ ensure the 10Gbps data transmission and the most densely installation capability as well as the lowest cost, currently it is well acknowledged as the ultimate choice for the 10Gbps fiber optic transceivers. Among them, Cisco SFP+ transceiver is the mainstream market. Cisco 10Gbase SFP+ transceivers are used for high speed 10Gigabit Ethernet, linking the equipment to fiber optic networks. Cisco SFP+ products include active SFP+ cables and SFP+ transceivers. There is also copper transceiver available from Cisco.

10G SFP+ Transceivers Introduction

10G SFP+ transceiver is one of Gigabit Ethernet fiber optic transceiver modules which are closely related with XFP, X2, Xenpak optical modules. SFP+ transceivers are mainly applied for Gigabit optical networking formation, with transmission rate of 300m, 10km, 40km, 80km. The connection type of SFP+ modules are dual-port LC.

SFP+ optical transceiver module is a new generation of Gigabit optical transceiver, it comply with the ANSI T11 protocol to meet the 8.5G fiber channel and Ethernet 10G applications. Compared with the earlier XFP optical transceiver, its appearance size has reduced about 30%, just is the same sized of the ordinary 1-4G SFP optical modules. SFP+ transceivers only retain the basic elecro-optic photoelectric conversion function, which has reduced the design of the original XFP SerDes, CDR, EDC, MAC, conversion function, thus simplifying the design of 1 0G optical transceiver module, as well as the power consumption. SFP plus optical transceiver has the obvious advantages such as higher-density, lower power consumption and lower system construction cost and other significant
features. The 10G SFP+ transceivers are widely used in Gigabit Ethernet fiber-optic data communications, and it has becomes the mainstream among the Gigabit modules.

SFP+ VS X2, XFP, Xenpak
They are all belong to 10Gigabit optical transceivers. SFP+ are more compact than X2 and XFP. Besides, SFP+ has a strong compatibility which can be interconnect and work together with other 10G XFP, X2, Xenpak optic transceivers. As to the price, the SFP+ has more advantages than other 10G transceivers.

SFP+ is similar with the SFP from the appearance, and they are all with LC connectors, but they are also different from each other: The transmission rata of them are different, SFP+ is 10Gbp/s optical modules, while SFP is generally 1.25G, 155M, 2.5G and other rate.

SFP-10G-SR is an typical Cisco compatible SFP+ transceivers which is hot swappable fiber transceiver module with 850nm VCSEL transmitter and PIN photo detector, The SFP-10G-SR fiber optic transceiver features low power consumption and it support multi-rate from 2G fiber channel to 10G Ethernet. Ingellen Technology Co., Ltd is a professional fiber optic transceiver OEM manufacture that provides the full range of 10G SFP+ transceivers and many compatible 10G transceivers for the market major brands including Cisco, HP, Finisar. The Cisco SFP-10G-SR modules are right one of the hot Cisco SFP+ transceivers that we recommend.

Typical Protocol Converter

protocol converter is  device used in telecommunications and networking to switch the protocol of one machine to match another protocol, as each protocol based on many factors. Protocol converter allows the different machines to work together — as long as the converter supports the protocols of each machine. The major protocol translation messages involve transformation of data, commands, representation, encoding and framing to achieve the conversion. Most converters have a database with several protocols, and this database is used to convert the initial protocol to another format.

The Protocol Converter connects directly to equipment and converts SNMP, BACnet, and Modbus protocols to one or more of these same protocols for integration into a building management system (BMS) or network management system (NMS). The protocol converter is ideal for situations where data from monitored equipment is incompatible with the protocols used by the BMS or NMS, such as in cases where legacy monitoring systems are present.

Applications of Protocol Converters
Protocol Converter applications vary from industry to industry. The protocol converter can be a software converter, hardware converter, or an integrated converter depending on the protocols.

Some of the key applications are:
Substation Automation;
Building Automation;
Process Automation.

Typical Types
Protocol converter provide local, remote loop-back functions, commanded remote device loop-back in addition to pseudo-random code testing functionality; loop-back functionality can be employed without influence on normal network data verbal exchanges and may definitely not end in this meltdown of network. Typical Protocol converters types include E1/V.35/V.24/RS485/RS232/RS422 protocol converter.

E1 to Ethernet Protocol Converter
E1 to Ethernet 10/100Base-T Protocol Converter adopts the ASIC chip which features simple circuits and compact structure and enhances the reliability of the integrated equipment. It provides data transmission channels at a maximum bandwidth of 2.048M for the Ethernet over coaxial cables and connects two LANs through coaxial cables. E1 port can certainly support 120 ohm/75 ohm amount of resistance in unison.

V.35 to Ethernet Converter
E1 to V.35 protocol converter provides physical conversion between ITU G.703 standard E1 interface and V.35 Interface. Equipments with V.35 interface but without G.703 interface such router and multiplexer is able to transmit data via E1 multiplexer or E1 channel with E1-V.35 protocol converter.

V.35 user port can certainly support N*64K (N=1~32) adaptive rate, which enables it to service central, additional and slave clock modes, so that you can possibly be taken to help a variety of apps; and it also can figure under DTE and DCE modes. E1 to V.35 protocol converter realizes the bi-directional data transfer from E1 port to V. 35 network. This equipment is used in communication network including WAN and LAN, realizing the transfer from E1 channel of SDH or PDH equipment to V. 35, which maybe provided by routers.

E1 to RS232 RS422 RS485 Converter
RS232 port can certainly service this a adaptive rate lower than 115.2K. Ethernet protocol convertor can certainly diagnose this giving in addition to having facts notice connected with E1 port on auto-pilot, in addition to switch off Ethernet function on auto-pilot.

Protocol converter are normally used with Switches, PCIe network cards and fiber media converters, CWDM and DWDM equipment, PDH multiplexers etc. Ingellen provides protocol converters for E1 to Ethernet Converter, V.35 to Ethernet Converter, E1 to V.35 or V.24 Converter and E1 to RS232 RS422 RS485 Converter, NxE1/ETH with E1/2E1/4E1/8E1/16E1 to ETH/2ETH/4ETH ports and tdm over ip converter, there are card types and standalone in 19 inch rack for choice.