First,DCS'sskeleton-thesystemnetwork,whichisthefoundationandcoreofDCS.网络对于DCS整个系统的实时性、可靠性和扩充性，起着决定性的作用，各厂家都在这进行了精心的设计。Asthenetworkofthesystemforreal-timeDCS,reliabilityandscalability,playadecisiverole,sothemanufacturershavebeencarefulinthisareaofdesign.对于DCS的系统网络，它满足实时性的要求，即在确定的时间限度内完成信息的传送。DCSsystemforthenetwork,itmu
First, DCS's skelet
on- the system network, which is the foundation and core of DCS.网络对于DCS整个系统的实时性、可靠性和扩充性，起着决定性的作用，各厂家都在这进行了精心的设计。
Asthe network of the system for real-time DCS, reliability and scalability, play a decisive role,
sothe manufacturers have been careful in this area of design.对于DCS的系统网络，它满足实时性的要求，即在确定的时间限度内完成信息的传送。DCS system for the network, it must meet the requirements of real-time, that is completed within defined time limits of information transmission.这里所说的“确定”的时间限度，是指在无论何种下，信息传送都能在时间限度内完成，而时间限度则是根据被控制过程的实时性要求确定的。Here called "OK" time limit refers to whether the circumstances, the information transfer can be completed within this time limit, but this time limit will be under the control of the process to be determined in real-time requirements.，衡量系统网络性能的指标并不是网络的速率，即通常所说的每秒比特数（bps），而是系统网络的实时性，即能在多长的时间内确保所需信息的传输完成。Therefore, network
performance measurement system is not the network speed indicators, known as bits per second (bps), but the network's real-time system that can ensure long time to complete the required information transmission .系统网络还非常可靠，无论在下，网络通信都不能中断，多数厂家的DCS均采用双总线、环形或双重星形的网络拓扑结构。Network also have to be very reliable in any case, network communications are not interrupted, so most manufacturers of DCS were double bus, ring or dual star network topology.满足系统扩充性的要求，系统网络上可接入的最大节点数量应比使用的节点数量大若干倍。Scalability to meet the requirements of the system, the system can access the network should be the maximum number of nodes than the actual number of nodes used in a large number of times.这样，一可以随时新的节点，另一也可以使系统网络运行于较轻的通信负荷，以确保系统的实时性和可靠性。In this
way, one can always add new nodes, it can also make the system run on less communication network load conditions to ensure the system's real-time and reliability.在系统运行过程中，各个节点的上网和下网是随时发生的，特别是操作员站，这样，网络重构会经常进行，而这种操作绝对不能影响系统的正常运行，，系统网络应该具有很强在线网络重构功能。Actual operation in the system process, each node of the Internet and into the net may occur at any time, especially operator station so that network reconfiguration will be conducted frequently, and this operation definitely not influence the systems up and running, so the system network should have a strong online network
