Have a temperature to Channel

have a temperature to Channel is a standard from the range of the memory networks.

Most STORAGE AREA network today Channel standards are based on the implementation have a temperature. The reached ranges are today with 4 Gb/s (4GFC), which in the full-duplex - enterprise for data transfer rates of 800 MB/s is sufficient. Ithowever even if smaller ranges are possible, then the maximum range was in has a temperature to Channel to a few years ago still 1 Gb/s (1GFC). As transmitting medium one finds copper cables and optical waveguide cable, the glass fiber is the most frequently used kind of cable with has a temperature to Channel.

Generally two can doTo kinds of have a temperature to Channel implementations to be differentiated, the Switched factory, which usually as if have a temperature to Channel, or briefly fiber plastic is called, and the Arbitrated loop, briefly FC-AL admits. With have a temperature to Channel Switched factory point-to-point connections between the terminals are switched, with have a temperature to Channel Arbitrated loop actsit itself around a logical bus, with which all terminals the common range divide.

Similarly as with classical networks, where each network map has an MAC address, Channel has each equipment a WWN with has a temperature (World Wide name). It acts thereby overa 64-Bit-Hexadezimalzahl, which has a temperature everyone to Channel equipment clearly identified. Beside the WWN still the WWPN used, here concerns it the World Wide haven name. Have a temperature to Channel of devices can more than only one haven have, in this case has the equipment further onlya WWN however it possesses WWPNs in the same number as it haven possesses. The WWN and the WWPN are usually very similar itself, then the two addresses differ usually only in a bit.

The extension cards, it the servers make possible overHave a temperature to Channel to communicate, adapters become (short as host bus: HBA) designates. Typical HBAs needs a PCI X card location with 64 bits bus width and at least 100 MHz clock rate.

have a temperature to Channel Arbitrated loop (FC-AL)

FC-AL also as Low Cost having a temperature Channel one designates, it forms frequently thatEntrance into the world of the STORAGE AREA network. One finds fiber plastic aluminum implementations frequent with smaller Clustern, in which it is possible several physical Nodes to access a common mass storage directly. Here SCSI reached its border, why one has a temperature the characteristic to Channel uses, thoseit permits to connect several host with several memory subsystems.

Have a temperature to Channel Arbitrated loop permits it to operate 127 devices at a logical bus. All devices the available range of 1 GB/s divide and/or. 2 GB/s. The wiring been made mostly star shaped by one has a temperature to Channel stroke, it is however also possible to connect the devices circularly there many has a temperature Channel devices over two in and/or. Exits order.

have a temperature to Channel Switched factory (FC-SW)

with have a temperature to Channel Switched factory acts it around the most efficient and fail safe implementation of have a temperature themselves to Channel,Switched factory is meant in most cases, if only of have a temperature to Channel one speaks. In the center of the Switched factory has a temperature Channel SWITCH or the Director is located. By this equipment all other devices are interconnected, so that it has a temperature to Channel SWITCH overpossible will to switch direct point-to-point connections between ever two arbitrary attached devices.

In order to increase the range further is it possible to build several HBA in a server. After itself each HBA servers with a PLog (haven Login), which its WWPN and WWN contains, toSWITCH announced, recognizes the SWITCHes by the uniform WWN on all connections that it concerns the same server and can thus the connections be bundled.

In addition these can be combined among themselves on use of several Switches. The Switches recognizes the topology then among themselvesand these use intelligently. Thus the smallest loaded way is always used. If the server is put for each HBA on another SWITCH had more than a HBA and, the server can reach thus a memory subsystem on several ways. This ability in has a temperatureChannel is called Multi Pathing. It increases the reliability and the achievement of the STORAGE AREA network (SAN), since between different devices more than a possible data path exists.

In order to increase the reliability further, one is in many has a temperature to Channel implementations in addition changed over, with redundantly binaryTo work factory. Thus two perfectly independent Switched are operated factory, each memory subsystem and each server are factory attached with at least a HBA at each of the two. The overall system can bear the loss of a whole factory apart from the loss of individual data paths even. This abilitythese aster particularly plays of the Recovery an important role within the range.

 

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