1000BASE-T VS 1000BASE-TX

As we talk too much about the advantages of fiber optic cabling over copper cabling, and too many knowledge about fiber optic transceivers, today, I would like to talk something about the copper-based Ethernet. As we know, copper-based Ethernet connections are limited to a data transmission distance of only 100 meters when using unshielded twisted pair ( UTP ) cable. But this is not the main topic of today’s discussion. Today’s main topic will be this: 1000BASE-T vs 1000BASE-TX.

In the past, Ethernet cable had a reputation for being slower than fiber optic cable, but that has started to change. The speed of copper-based Ethernet was once limited to 10 Mbps. However, “Fast Ethernet” offers speeds of up to 100Mbps, and “Gigabit Ethernet” can provide speeds of up to 1000Mbps over twisted pair. Thus, IEEE 802.3ab, which defines the widely used 1000BASE-T interface type, uses a different encoding scheme in order to keep the symbol rate as low as possible, allowing transmission over twisted pair. 1000BASE refers to a Gigabit Ethernet connection that uses the unfiltered cable for transmission. “T” means twisted-pair cable (e.g. the common Cat5 in use today).

1000BASE-T

1000BASE-T (also known as IEEE 802.3ab) is a standard for Gigabit Ethernet over copper wiring. Each 1000BASE-T network segment can be a maximum length of 100 meters (330 feet), and must use Category 5 cable or better (including Cat 5e and Cat 6). 1000BASE-T can be used in data centers for server switching, for uplinks from desktop computer switches, or directly to the desktop for broadband applications. 1000BASE-T allows autonegotiation between 100Mbps and 1000Mbps. A big advantage of 1000BASE-T is that existing copper cabling can be used instead of having to rewire with optical fiber.

1000BASE-TX

1000BASE-TX is a physical layer standard similar to 1000BASE-T created and managed by Telecommunications Industry Association (TIA) (1000BASE-TX is also referred to as TIA/EIA 854). 1000BASE-TX uses two pairs of wires, instead of four, for data transmission which enables transmitting data at speeds of gigabits per second on category 6 and 7 cables. It is also maintained under the IEEE 802.3ab standard. Though 1000BASE-TX enables the building of devices with less circuitry to support, it has not been as commonly used as 1000BASE-T, due to the high cost of Category 6 and 7 cable requirements and the falling cost of 1000BASE-T products.

1000BASE-T vs 1000BASE-TX

1000BASE-T is designed to operate over 4-pair UTP cable and supports full-duplex data transfer at 1000Mbps. But 1000BASE-TX operated over only two of the four pairs in the cable. 1000Base-TX transmits data at 500 Mbps on two pairs and receives data on the remaining two pairs at the same data rate. In addition, delay skew, which is the difference between the slowest and fastest pairs within a cable, becomes increasingly important as data rates increase. This depends that Cat 5 cabling can be used with the 1000BASE-T standard. But 1000BASE-TX requires Cat 6 cabling. Furthermore, 1000BASE-TX standard can also be implemented with simpler electronics.

At present, 1000BASE-T is more commonly used with the lower cost of Cat 5 cabling. However, the design of 1000Base-TX does not require hybrids, nor does it necessitate echo cancellation. Consequently, the design of 1000Base-TX allows for its electronics to be much less expensive than comparable 1000Base-T electronics. So, which is better? It must depend on the plan, budget and application of your project.

Related Recommendation

1000BASE-T SFP Gigabit Ethernet RJ45 100m or 10/100/1000BASE-T Gigabit Ethernet Auto Negotiation Copper SFP $16.00

Original article source:http://www.fiber-optic-transceiver-module.com/

The Introduction of SFP Modules

Even though we cannot see the fiber optical communications products frequently in daily life, our life is closely related to them. In fiber optical communications field, fiber optic transceiver module is widely used by high-speed communication systems. And as the indispensable part of transceiver module, SFP (Small Form-Factor Pluggable) have gained much attention around the world.

The SFP is a compact, hot-pluggable transceiver used for both telecommunication and data communications applications, which are designed to support SONET, gigabit Ethernet, Fiber Channel, and other communications standards. SFP now can reach 4G at the highest and often use the LC interface. Because of its smaller size, SFP can be configured more than double of ports on the same panel. Moreover, most functions of SFP are the same as GBIC (Gigabit Interface Converter). So the SFP is sometimes referred to as a Mini-GBIC although no device with this name has ever been defined in the MSAs.

There are many kinds of SFP modules according to different transmitter and receiver types, allowing users to select the appropriate transceiver for each link to provide the required optical reach over the available optical fiber type, such as multi-mode fiber or single-mode fiber. Optical SFP modules are commonly available in these categories.

SX - 850 nm, for a maximum of 550 m at 1.25 Gbit/s (gigabit Ethernet) or 150m at 4.25 Gbit/s (Fibre Channel),with multi-mode fiber
LX - 1310 nm, for distances up to 10 km, with single-mode fiber
EX - 1310 nm, for distances up to 40 km, with single-mode fiber
ZX - 1550 nm, for distances up to 80 km, with green extraction lever (see GLC-ZX-SM1),with single-mode fiber
EZX 1550 nm, for distances up to 160 km, with single-mode fiber
TX：Electrical Modules，for distances up to 100m
CWDM：Coarse Wavelength Division Multiplexing
DWDM：Dense WaveLength Division Multiplexing
BX - 1490 nm/1310 nm, Single Fiber Bi-Directional Gigabit SFP Transceivers, paired as BS-U and BS-D for Uplink and Downlink respectively, also for distances up to 10 km. Variations of bidirectional SFPs are also manufactured which use 1550 nm in one direction.

Due to the important role SFP modules played in the fiber optical communication field, many scientific companies have paid much more attention to the SFP. Because of its hot-pluggable function, SFP modules can be connected or cut by the equipment without cutting the power. And this function also makes it possible for the administrator to upgrade or extend the system without affecting the users online. Moreover, the SFP modules make the maintaining work more simple. Meanwhile, because of the heat exchanging function of SFP, we can make the overall plan for the cost of sending and receiving, link distance, and all the network topology according to the network upgrading demand, instead of changing all the system board.

Through the above introduction, you will know what SFP module is, the different types of it and the main functions of SFP module. Nowadays the SFP optical module has become the most frequently used fiber optical transceiver module in the fiber communications industry. And the prospects of it has also been widely noticed by fiber optical communications field.