The design of network technology and integrated wiring system

1:fddi/cddi (Fiber/copper Distributed Data Interface)





2:ATM (Asynchronous transfer Mode)





3:fast ETHERNET (Fast Ethernet)





below analyze these three kinds of technology:





1:fddi/cddi (Fiber/copper Distributed Data Interface)





This is a mature, non-carrier listening, 100M bandwidth sharing network technology. The use of token delivery service strategy, network equipment between the main ring and vice-ring, in the network line or network equipment failure, there is a strong ability to self-reconfigurable. At the same time, its station management (SMT) function is very powerful, suitable for the backbone network. But its technical difficulty is high, the price is expensive, the expansibility is poor, is in the circular wiring, is not very compatible with the ATM.





2:ATM (Asynchronous transfer Mode)





This is a kind of advanced asynchronous mode based on the optical fiber transmission system, the application of statistical multiplexing technology, the use of SMS Exchange technology. It directly supports data, video, audio and other multimedia transmission. The speed is quite fast (reach 155m,622m), because the asynchronous mode is used, the efficiency is quite high, which is suitable for the backbone grid. However, it is still a controversial technology, many standards have yet to be improved, interoperability between different manufacturers of products and versatility needs to be further improved.





3:fast ETHERNET (Fast Ethernet)





today's high-speed Ethernet technology generally includes two kinds: 100M Vg-anylan and 100m-t. This is mainly about the latter--fast switching Ethernet. Although the 100M Ag-anylan provides the multimedia function, but its compatibility is poor, the price is high, the complexity is high, does not consider here. 100BASE-T is a modified variant of 10BASE-T, it is based on the original use of the mesh division into several network segments, the division of the conflict domain, and the adoption of buffer exchange, so that the grid on the transmission rate and transmission efficiency greatly improved.





Fast Ethernet is practical (compatible with the original Ethernet, software, hardware-rich, advanced (fast--100mbps), easy to upgrade (easy to ATM or faster grid conversion), scalability (through interconnection devices, switches, routers easy to expand), open good (software and hardware agreement open), cheap ( Compared to ATM, FDDI, supported by more manufacturers (with Intel, Sun, 3com, Bay, Accton and other large companies) features. For the multimedia grid application, Fast Ethernet can also meet the requirements well.





Although the effective distance between Ethernet grid devices is short (100 meters), suitable for departmental small LAN, but can use heart fiber optic converter and optical fiber to extend the transmission distance.





Fast Ethernet has excellent scalability, using switched hubs and common hubs, the expansion of the number of users has no effect on the grid (can be extended when it is in use) to facilitate future subnet access.





based on the above analysis, combined with the main points of the integrated wiring system and grid technology, this paper provides three kinds of integrated wiring scheme for readers.





: The use of all twisted-pair structure cabling Scheme (Fast Ethernet technology)





This scheme is the whole wiring system (vertical subsystem, horizontal subsystem, work area subsystem, equipment among subsystems, wiring subsystem) all use five types of twisted-pair, network technology is the use of Fast Ethernet technology (see design Diagram i).





advantages are: low-cost wiring, grid equipment cheap, easy to manage, Fast Ethernet technology is quite mature, its exchange is carried out in the second layer, without human intervention.





disadvantage is: if the floor is higher, this may lead to some dwelling point wiring length more than 100 meters, as we all know, according to the wiring principle, twisted-pair line generally does not allow more than 100 meters, this will cause the signal attenuation and even distortion.





second, because all the wiring from the center room through the vertical subsystem to the other floors of radiation, the shaft requirements higher.





is followed by the full twisted pair structure is difficult to upgrade to ATM technology or Gigabit Ethernet technology, ATM technology and Gigabit Ethernet technology need to use Single-mode/multimode fiber to connect the components of the backbone.





Two, uses the optical fiber to form the vertical backbone, the twisted pair line is the Edge wiring scheme (ATM technology)





the vertical subsystem of this scheme uses the fiber structure, the other subsystems adopt five kinds of twisted-pair wiring, and the network technology is ATM technology.





Advantage is: First wiring cost is cheaper (compared with scheme one, only slightly higher).





second, the vertical subsystem is greatly simplified, just from the center of the room to the other floor radiation fiber, each floor to allocate a fiber (preferably with backup line), in each floor, five types of twisted-pair wiring, the wiring of the time complexity and space complexity greatly reduced, and 100 meters length limit problem no longer exist, Because the fiber is not limited by the short distance (single-mode 15 km, multimode 1.5-2 km).





is followed by one-step, the direct use of advanced ATM switching technology, will make the network response speed greatly improved.





disadvantage: Mainly network equipment and host equipment is quite expensive. Thanks to the advanced ATM switching technology, the corresponding ATM switches, ATM emulation bridges, ATM adapters must be configured, and these devices are extremely expensive. and ATM switches need special management, based on the current technology, ATM exchange functions can not be fully automated, but according to the parameters of people to work, management by a certain limit.





the pros and cons of integrated programme I and Programme II, the third proposal is presented here.





III: The use of optical fiber to form a vertical backbone, twisted-pair cable for the edge of the wiring scheme (Fast Ethernet technology) 3lian.com





is to use the network technology of scheme one and the wiring way of scheme two. Optical fiber is used in the vertical subsystem, and the other subsystems are composed of five kinds of twisted-pair wires. The network technology uses the fast switching type Ethernet.





advantages: cheap wiring, reasonable cost of network equipment, no special configuration of host equipment, easy to upgrade. and Ethernet switching technology does not need human intervention. All automatic exchange and convenient management are implemented. And when you need to upgrade to ATM or Gigabit Ethernet technology, only need to replace the network equipment, no need to replace wiring equipment, truly achieve "a wiring, life-long benefit" goal. However, when the system needs to be upgraded, some network devices must be replaced.





The above three kinds of integrated wiring schemes have their advantages and disadvantages, however, from the network hardware layout of the diagram, taking into account the relationship between the performance price and future upgrades and maintenance, I think, under the current network technology, select a third cabling scheme more reasonable scientific