scada protocols

, we can access the class by means of the protocol, without knowing the source code of the class.11. The protocol is defined using the @protocol Directive and the @end directive, where only a few methods can be declared. The declared method is @required type by default, that is, the class that adheres to this protocol must be implemented. If there are options to implement , use @optional to define. The template is defined in the H file as follows:@protocol Xprotoc...//method list name, declared

Network layer—The IP protocol belongs to the network layer of the network protocol stack. The functional goal of this layer is to transfer packets from one location in the network to another, which is the lowest level of processing end-to-end transmission. In the middle of the transfer process passes through many hop (hop) intermediate routers, so the routing algorithm is the core task of its design. (but unfortunately not the core task of this article) Tunnel—When two of the same networks are s

Code:@import Foundation;/**************************************** * Person class ****************************************///to adopt a protocol, you need to list the name of the Protocol in the Declaration of the class and enclose it in angle brackets .//With multiple protocols, the names of the protocols are separated by commas, such as: //multiple protocols can

Analysis plan of RIP routing protocols V1 and V2 is as follows: R1 connects to the Internet through a port and uses loopback to simulate the IP address of the host carrying the router R1: lo 0: 10. 1.1.1/24 f0/0: 192.168.0.1 www.2cto.com R2: lo 0: 10. 1.2.1/24 f0/0: 192.168.0.2 configuration: R1 R1 (config) # int lo 0R1 (config-if) # ip add 10.1.1.1 255.255.255.0R1 (config-if) # int f0/0R1 (config-if) # ip add 192.168.0.1 255.255.255.0R1 (config-if) #

This article describes the basic working principles of routers in TCP/IP networks and introduces several functions of IP routers, the static and dynamic routing protocols, as well as the concepts of the internal gateway protocol and the external gateway protocol are given, at the same time, the most common RIP, OSPF, BGP and BGP-4 routing protocols are briefly introduced, and then the design objectives and

, intuitive, and efficient. Due to the large amount of information transmitted by digital videos and limited bandwidth, the compression and encoding of videos, selection of transmission channels and network protocols, and IP Multicast technology (IP Multicast) software Implementation Based on the Windows operating platform has become a key technology in network-based digital video transmission applications. Among them, the choice of transmission chann

languages. By using source code and documents, you can understand the architecture of the entire software and the implementation methods of a specific function. Object Code refers to the object code generated after the source code is compiled, similar to the "class library". It provides various interfaces for others to use. According to my understanding, it is something like common DLL, ActiveX, OCX controls. (I don't know if this is correct) The purpose of these two concepts is to make it clea

Many people may be familiar with the term Router Protocol, especially the rapid development of the network, the Internet Router Protocol is constantly improved, and many new features are also emerging. The wide application of information technology in various fields has promoted the rapid development of information exchange networks. Internet is the biggest beneficiary. The main node and device of the Internet network are routers. The router technology determines data forwarding through routing.

For various reasons, many networks adopt multi-route protocols. This phenomenon is usually caused by merger and acquisition activities, or temporary occurrence during the migration. Many vro hardware manufacturers may use a variety of proprietary protocols to connect with standard protocols. Some routers will run more than one protocol and inevitably receive the

and provides services related to the existing GSM system. Core networks can connect users to various external networks and business platforms, such as circuit switched voice networks and packet switched voice networks (IP voice networks), data network, Internet, Intranet, e-commerce, SMS center, etc. 2. UMTS systems mainly include the following interface types: (1) B interface: MSC (vlr;(2) D Interface: MSC (HLR;(3) E interface: MSC (MSC;(4) GC interface: ggsn (HLR;(5) GJ interface: ggsn (exter

For various reasons, many networks adopt multi-route protocols. This phenomenon is usually caused by merger and acquisition activities, or temporary occurrence during the migration. 　　 Many vro hardware manufacturers may use a variety of proprietary protocols to connect with standard protocols. Some routers will run more than one protocol and inevitably receive t

Many people may not have a special understanding of Static Routing and dynamic routing protocols. Here we mainly introduce the RIP and OSPF routing protocols. Static Routing is a fixed route table configured on the router. The static route does not change unless the network administrator intervene. Because Static Routing cannot reflect network changes, it is generally used in a network with a small network

Through understanding the computer network, its layer-7 structure has different protocols to regulate. Based on the network type, we can divide these protocols into LAN protocols and generalized network protocols. Now let's talk about what protocols are included in the broad

Network Protocol in SQL Server To connect to the SQL Server database engine, you must enable the network protocol. Microsoft SQL Server can process requests through multiple protocols at the same time. The client connects to SQL Server using a single protocol. If the clientProgramIf you do not know which Protocol SQL Server is listening for, you can configure the client to try multiple protocols in sequen

"Original" https://www.toutiao.com/i6592813624689951239/ Overview⊙TCP/IP is a protocol group that can be divided into three levels: Network layer, Transport layer and application layer.At the network layer are IP protocols, ICMP protocols, ARP protocols, RARP protocols, and BOOTP protocols.There are TCP

With the development of the routing industry, both the router technology and the routing protocol are constantly improved, making the routing technology more standardized, the previous lecture on VPN routing and forwarding focuses on configuring and verifying VRF (VPN route forwarding. In the above circumstances, users must be isolated from a shared device. In that article, I did not define the communication mode between each user outside the shared interface, such as Static Routing Protocol or

Network protocols play an important role in movie servers. It can be said that without network protocols, movie servers will not be able to play a normal role. This article briefly introduces several mainstream network protocols, hoping to help you understand the film server. 1. FTP: File Transfer Protocol). This Protocol allows you to upload and download files b

How CAN we identify unfamiliar CAN network protocols ?, Identify the can protocol --> In the CAN network, data transmission and receiving of all nodes share a bus. In the face of an unknown multi-node CAN bus network, how CAN we accurately analyze the communication protocols between nodes? 1. CAN bus communication Similar to 485, CAN-Bus communicates with each other in the form of a Bus. All CAN nodes a

The previous article analyzed the overall concept of the Internet, from bottom to bottom, and the design philosophy of each layer of protocol.This is a question from the designer's perspective. Today I want to switch to the user's perspective to see how users interact with these protocols from top to bottom. ========================================================== ================================= Getting started with Internet

Network is a tool that everyone can't do without. It is becoming more and more active. How much do you know about these computer network protocols? Understanding the use of these protocols can help us use computer networks more rationally. Now, we will introduce several commonly used computer network protocols for literacy. Computer Network Protocol 1, HTTP Engli