District Government Computer Office Network Design

Chapter 1 Overview At present, the climax of planning and construction of information highways has taken place in the world. As a prototype, there are nearly tens of millions of connected computers on the international Internet, and hundreds of millions of people around the world exchange information on the Internet. And various business processes. The Internet has accumulated a large amount of information resources, which involve information on various fields, industries and social public services that human beings face and engage in. Become the largest information base that can be shared globally in the information age.
At present, due to the continuous development of networks, databases and related application technologies, especially the extensive application of international Internet and intranet technologies, the world is entering the era of network center computing. People's traditional interactions and working patterns are changing. People in different geographical locations can share data, use groupware technology to work together; multimedia data storage, transmission, and application technology continue to mature; the development of these computer technologies affects traditional computer business systems, enabling users Can be more convenient. The more intuitive use of the system also makes the system more complete and more powerful.
The goal of xxx district government office network construction is simply to connect various different information resources in the xxx district government office network through high-performance network equipment to form an intranet inside the xxx district government office network campus. The system accesses the WAN through a routing device.
It is not an easy task to build a government office network in the xxx area. It requires careful argumentation, careful decision-making and intense construction. When a bunch of devices became a network, the enthusiasm of most office workers slowly cooled and solidified. The xxx district government office network has been built, and various problems have emerged: the design goals are simply not realized, there is no suitable software to apply, many ideas cannot be implemented at all, and the subsequent maintenance costs are unbearable.
In response to the demand put forward by the computer network, combined with the practical experience of building various types of system integration projects over the years, we propose a design scheme for computer network construction, hoping to best solve the user's actual application problems. At the same time, due to the possible deviation of our understanding of the user's specific situation, the entire program may need to communicate with the user further during the implementation process.
Chapter II System Analysis I. Design goal of government office network in xxx area Because the network is a new concept, the development in China is still immature, so whether it is office, media or computer industry, the network is lacking in comprehensive and in-depth Understanding and understanding, with a certain degree of blindness and prejudice, do not know what role the Jinbei network should play.
The network lacks the appropriate software to apply. The so-called network is now a solution proposed by some system integrators based on advanced hardware devices, which is device integration. Because network technology is a relatively new technology, many people have the idea of ​​"paying attention to hardware and ignoring software." There are also few software companies that have invested in developing software in this area, resulting in a lack of software. Focusing only on the construction of tangible networks and neglecting the construction of intangible culture is the most critical reason for network failure. The "intangible culture" referred to here refers to things that people cannot see or touch, such as the concept of work, the way of work, the structure of interests, and the mode of operation and management of the office. In a sense, the construction of the Internet is not only related to technical issues, but will be extended to a deeper level, which means that a revolution brought about by information technology will completely change our way of life and work. .
The more expensive the network solution, the better? As a supervisor, it is necessary to study what kind of use will be used in the future, and whether the potential of these devices can be utilized, and whether these devices can meet the needs of future development. However, most of the current network system integration is the integration of advanced equipment, ranging from hundreds of thousands to millions, usually several million and tens of millions. Spend millions of networks built with atm technology for file sharing.
Based on the above conditions, we propose that the goal of xxx district government office network construction should be:
First, the construction of the network platform: building a center of office automation, computer-aided office, modern computer xxx area government office network culture and office automation, relying on modern network technology, advanced technology, strong scalability, can cover the main The main network of the government office network of the xxx area of ​​the building connects the various PCs, workstations, terminal equipment and regional networks of the office, and remotely interconnects with the relevant regional network through the internet to promote themselves and Get internet resources online.
Second, office automation: form a computer network system of xxx district government office network with reasonable structure and internal and external communication. On this basis, establish a software and hardware environment that can meet the needs of office, scientific research and management work, develop various information bases and apply The system provides adequate network information services for all types of office workers. The overall design of the system will fully reflect the technological advancement, high security and reliability of the system in line with the principles of overall planning and distribution implementation, and at the same time have good openness and scalability. In the interest of the office, the rational use of construction funds, so that the system is economically viable. Establish oa paperless automated office system.
Third, anti-theft monitoring: According to the actual situation of the government office network in xxx area, establish a monitoring and anti-theft system. It is required to observe and record the activities of personnel in all major places, and act as the patron saint of the government office network of xxx area, and discover various security in time. Hidden dangers and violations are easy to effectively deal with and stop the further development of accidents. In addition, some investigations and treatments provide some inquiries in the future to create a safe living environment and improve management.
Fourth, video conferencing: Considering the needs of the current office network, we will implement an efficient video conferencing system through the support of the office automation system for use in conferences, business meetings, group discussions, and in meetings, The language and information of the participants are accurately communicated.
Fifth, wireless office network: Based on the consideration of the advanced nature of network design, we adopted wireless network technology in the design of the program. The trednet wireless networking product family follows the most advanced iee network standards, giving you the freedom to configure your network. You can share network resources anywhere you want. You can freely connect to the network to share network resources in the office without the need for cables.
Sixth, lightning protection system: In order to ensure network security, we should use lightning protection system, so that our network can effectively avoid the harm of lightning strikes on network equipment. This part of the work will be carried out after the construction of the network system.
Second, the overall design idea of ​​the government office network network in xxx area
The xxx district government office network is not only related to technology, but includes the integration of many components such as network facilities, application platforms, information resources, professional applications, and personnel quality, as well as information-based office environment systems. Therefore, how to plan, organize network construction and develop the design ideas in general is the most important issue in the construction of xxx district government office network.
The overall design is xxx

The overall idea and engineering blueprint for the construction of the office network of the district government is the core task of building the network of the government office network in the xxx area. The overall design of the xxx district government office network is first carried out to conduct object research and demand survey, to clarify the nature of the office, the tasks and the characteristics of reform and development, to accurately describe the information environment of the office, and to clarify the needs of the system construction and Conditions; Secondly, based on the analysis of the application requirements, determine the type of office intranet service, and then determine the specific objectives of the system construction, including network facilities, site settings, development and management and management; third is to determine the network Topology structure and function, according to the application requirements, construction goals and distribution characteristics of the main office buildings, system analysis and design; Fourth, determine the technical design requirements, such as technology selection, wiring design, equipment selection, software configuration, etc. The standards and requirements of the aspects; Fifth, plan to implement the implementation steps of the construction of the government office network in the xxx area.
Whether the overall design of the xxx district government office network is scientific, depends on whether it can meet the following basic requirements:
1. Overall planning arrangements. Starting from the overall and comprehensive work needs of office construction, consider the geographical distribution and communication conditions of the department. The overall planning network construction plan provides for the major issues such as the objectives, overall structure, service functions, budget, and construction steps of the network system.
2. Combination of advanced, open and standardized. Try to adopt more mature technologies that conform to international industry standards, take into account the development direction of network technology, and choose structured, scalable, and versatile network products to ensure that the network does not lag behind for a long time.
3. Reasonable structure. It has a good layered design in communication network, resource configuration, system service and network management, which makes the network structure clear, easy to use, manage and maintain.
4. Efficient and practical. Focusing on the actual needs of office, scientific research and management, we will give priority to solving the urgently needed problems with limited funds. The equipment is easy to use and maintain. Provide advanced platforms for scientific research, such as visual computing, computer collaborative operations, virtual networks, virtual reality, computer simulation, remote computers and data processing.
5. Support for broadband multimedia services such as telecommuting, multimedia network offices, video conferencing
6. Provide a good environment for academic exchanges and high-speed interconnection with the internet, quickly access the internet, exchange information with colleagues at home and abroad, work collaboratively and display the image of the office.
Third, user needs analysis
XXX District Government Office Network Construction This project is a basic construction project, mainly to complete the task of building a network platform. Our years of experience in various types of integration projects prove that the network platform is only a stage, and the dominant role is the application system. Although there is no specific requirement for this part in the user, we are responsible for the user, in the design of the program, on the one hand, to complete the user's current construction needs, on the other hand, consider the user's future application development, and propose the future of the user. Apply some suggestions for advice so that users can best achieve their initial construction goals.
The construction tasks of the government office network in the xxx area can be summarized as follows:
● The xxx district government office network cabling project completes the structured cabling project and information system integration inside the office building.
● Network equipment is equipped with network switching equipment to realize Gigabit fiber connection between buildings to ensure the implementation of various systems in the future.
● The network management system design provides a Chinese graphical interface tool that can manage the entire network system, so that system maintenance personnel can centrally control all the devices on the network.
● Internal and external network isolation The office area network and the external network are isolated by a hard disk isolation card, a dual wiring system, and a dual network device.
The third chapter xxx district government office network network system design scheme network system is the operating platform of the application system, in the overall system construction is in a basic position. The design of the network system must be based on the user's specific situation and actual application requirements. The government office network of the xxx area has the actual characteristics of a large number of buildings, a complex network structure, and a huge amount of traffic due to the presence of video on demand in the future. Therefore, in the design of network systems, network technology selection and network device configuration are issues that need to be considered.
First, the principle of network technology selection and selection We consider the following characteristics in the design of the network system:
A stable and reliable network is a reliable network only when the network is stable. The reliable operation of the network depends on many factors, such as the design of the network and the reliability of the product. Choose a system with the experience of operating such a network. Network partners are even more important. Backup technologies for the physical layer, data link layer, and network layer are required.
In order to support the transmission capability of data, voice, and video multimedia, the high-frequency width must reach the current international advanced level in technology. To adopt the most advanced network technology to adapt to the transmission of large amounts of data and multimedia information, both to meet current business needs, but also to fully consider future developments. For this purpose, high-frequency wide advanced technology should be used.
The scalable network system needs to be scalable and scalable. As the business grows and the level of application increases, the data and information flow in the network will grow exponentially, requiring good scalability of the network. And can continue to upgrade with the development of technology. Easy to expand not only refers to the expansion of the device connection, but also the scalability of the network structure: that is, only when the network structure is designed properly, the new network node can easily join the existing network; Easy extension of the agreement: Whether it is to choose a Layer 3 network routing agreement, or to plan the division of the second layer of virtual network, you should pay attention to its expansion capabilities.
Qos guarantees that with the increasing use of multimedia in the network, such application requires higher quality of service, and the network system should be able to guarantee qos to support such applications.
The security network system should have good security. Security management is very important because all users inside the network connection campus. It should support the division of vlan, and can carry out effective security control when the third layer exchange between vlans to ensure the security of the system.
Easy to control and manage Because there are a lot of Internet users, how to manage their communication, to ensure the quality of a certain user communication, and to make reasonable use of network resources, is the primary problem facing the establishment of a network.
Ipmulticast Because the xxx area government office network contains many multimedia applications, there will be a lot of broadcast information, which takes up a lot of bandwidth resources. Therefore, in this project, the network system should be able to support ipmulticast, which can reduce unnecessary broadcasts in the network.

Save the bandwidth of the trunk.
Network that conforms to the trend of ip In the current network of any service provided, the support service for ip is the most common, and the ip technology itself is in the process of development, such as ipv6, ipqos, ipoversonet and other emerging technologies. Increasingly, the xxx district government office network must follow the pace of ip development, that is, must choose the network vendors in the ip development leadership position.
The selection of backbone network technology In the construction of the government office network in the xxx area, the choice of network technology for the backbone network plays a decisive role in the success of the network construction. Choosing the mainstream network technology suitable for the characteristics of the xxx area government office network network not only ensures the high performance of the network, but also ensures the advanced and expandable network, and can smoothly transition to the update technology in the future to protect users. investment.
According to the requirements of the users, our backbone network can use Gigabit Ethernet technology. Currently popular regional network and metropolitan area network technologies mainly include Ethernet, Fast Ethernet, ATM, fddi, cddi, and Gigabit Ethernet. Among these technologies, Gigabit Ethernet is gradually taking the mainstream position in its support for high-bandwidth, multi-transport media, multiple services, and guaranteed qos in the area network.
1. Introduction of existing network technology Ethernet is the most widely used network technology. It is based on the csma/cd mechanism and uses shared media to achieve communication between computers with a bandwidth of 10mbps.
The csma/cd technology uses bus control technology and backoff algorithm. When a station wants to transmit, it first needs to listen to the bus to determine if there is a transmission signal from other stations on the medium. If the medium is idle, it can be transmitted. If the medium is busy, it will be retransmitted after an interval, that is, some backoff algorithm is adopted.
In the early days of Ethernet, due to its media sharing characteristics, when the number of sites in the network increased, the performance of the network would drop rapidly, and there was a lack of support for multiple services and qos. With the development of network technology, the current Ethernet technology has evolved from sharing technology to switching technology. The emergence of Ethernet switching has greatly improved the traditional shared Ethernet technology. All nodes on the shared local area network share the same bandwidth. When two arbitrary nodes on the network exchange data, other nodes can only wait. Switching Ethernet uses network switches to establish multiple exclusive connections between different network segments, using directional transmission by destination address, providing dedicated frequency bands for each individual network segment, increasing network transmission. Throughput, the transmission rate is increased, and there is no collision problem on the backbone network. The combination of virtual network technology and switching technology effectively solves the broadcast problem, makes network design more flexible, and makes network management and maintenance more convenient. Switched Ethernet has overcome the shortcomings of shared Ethernet, and with the new development of ip technology, such as ipmulticast, ipqos and other technologies, the exchange Ethernet can support multimedia services and other business services.
Fast Ethernet Ethernet Fast Ethernet technology is still Ethernet, but also bus or star-shaped network. Fast Ethernet still supports sharing mode. In shared mode, it still uses broadcast mode, so in shared mode. The fast Ethernet network inherits all the features of the traditional shared Ethernet network, but the bandwidth is increased by 10 times. The application of Fast Ethernet is mainly based on its switching mode. In the exchange mode, the fast Ethernet network has no defect of the mechanism of csma/cd. In addition to the advantages of the Ethernet exchange mentioned above, the fast Ethernet in the exchange mode can work in the full duplex state. So that the network bandwidth can reach 200mbps. Therefore, Fast Ethernet is a very good network technology with good performance and price ratio in regional network technology. It can provide good network quality and service in supporting the application of multimedia technology.
Asynchronous transfer mode
As a new switching technology, atm has its obvious advantages. Atm is a network technology that combines the advantages of packet switching and circuit switching. It uses a fixed-length 53-byte small frame format, of which 48 bytes are the payload of the information, and another 5 bytes are Cell head. For the payload to be checked at the intermediate node, the verification of the information is performed in the end device of the communication to ensure a high transmission rate and a low delay.
Atm was originally designed for use in public networks, but it has now become the center of private network development, and has already entered the market in the experimental stage. This change is due to the efforts of organizations such as the atm forum. The rapid development of the atm forum truly demonstrates the growing interest in atm. The atm forum has now attracted more than 700 companies from the public and private networks and the computer industry, leading many advanced customer organizations, telecom service providers and independent software vendors.
Atm, metro, and public networks, ATM is being used primarily because it can multiplex multiple services onto one infrastructure to meet the growing demand for more powerful desktops. It can also provide new network services such as virtual lan and multimedia.
However, atm technology also has its drawbacks. First, the standards have not yet been fully developed, and many important standards are still being revised. This has affected the promotion of atm technology, especially in the area of ​​regional networks. Secondly, atm technology is currently used in the range of private networks and core networks, and the traditional network technology is extended to both the peripheral and the client. This makes it necessary between the ATM network and the traditional network. Establish an intermediate connection layer, which is a technology that converts between ATM cells and traditional network frame structures, such as classicip and atmlane. The advantage of this technology is that traditional networks can be connected to atm. In the network, the disadvantage is that it brings a lot of resource overhead, which greatly increases the complexity of the ATM network and reduces the overall performance of the network. In addition, most of the current network applications are mainly based on the application of the ip network, and the application of the ATM cell directly is very small, which also greatly increases the complexity of the use and management of the ATM network.
Gigabit Ethernet technology Gigabit Ethernet technology is based on simple Ethernet technology and provides 1gbps bandwidth for the backbone of the network. Gigabit Ethernet technology is a natural way to upgrade the skills of existing Ethernet networks, workstations, management tools and management personnel. Compared with other high-speed network technologies of comparable speed, Gigabit Ethernet is relatively inexpensive and relatively simple, such as retaining Ethernet's frame format, management tools, and understanding of the network concept.
Gigabit Ethernet is a fairly successful extension of the 10mbps Ethernet and 100mbps Fast Ethernet connection standards. Now the mature standard of Gigabit Ethernet is ieee802.3z, the goal of ieee802.3z is:

Use the ieee802.3 frame format;
Full duplex and half duplex can be used;
Csma/cd is still used in shared mode;
Backward compatibility with installation media;
The transmission speed is ten times higher than that of the fast Ethernet, and one hundred times higher than that of the Ethernet.
Gigabit Ethernet extends the line distance from 500 meters to 3000 meters through carrier expansion, network equipment with relay and switching functions, and a variety of lasers and optical fibers. If the 1300nm laser and 50um multimode fiber are used, the transmission distance can reach 3km. Now, the Gigabit Ethernet interface on some manufacturers' switches also supports the longhaul standard, which can support transmission distances of up to 60km.
Gigabit Ethernet provides higher bandwidth and is the third member of the powerful Ethernet family. Use switches or routers to connect with existing low-speed Ethernet users and devices, because the frame format and frame size of Gigabit Ethernet are the same as all Ethernet technologies, and do not need to do anything to the network. change. This upgrade method makes Gigabit Ethernet a better choice for economic and management performance than other high-speed networking technologies.
In the intranet application, there are many new application requirements, including video and audio. In the past, it was thought that these applications with high latency requirements could only be implemented on a network such as ATM. However, some new technologies and new standards have enabled the Gigabit Ethernet network to support video well in regional networks. And multimedia data such as audio.
The design of the Gigabit Ethernet is very flexible and has almost no restrictions on the network structure. It can be switched, shared or router-based. The network interconnection technologies currently being applied, such as specific ip switching technologies and Layer 3 switching technologies, are fully compatible with Gigabit Ethernet. Gigabit Ethernet can be implemented with inexpensive shared hubs, switches or routers. Gigabit Ethernet supports full-duplex cabling between new switches or switch-workstations, and half-duplex cabling mode to connect to shared hubs based on csma/cd access.
Transmission media used in Gigabit Ethernet networks are fiber optics, Category 5 non-prohibited twisted pair or coaxial cable. Currently, Gigabit Ethernet supports multimode fiber, multimode fiber and coaxial cable, and standards supporting Category 5 non-forbidden twisted pair are under development.
The table below lists the distance standards currently supported by Gigabit Ethernet.
Standard name media transmission distance
1000base-sx wavelength 850nm62.5 micron multimode fiber 50 micron multimode fiber 275 meters 550 meters
1000base-lx wavelength 1300nm62.5 micron multimode fiber 50 micron multimode fiber 9 micron or 10 micrometer multimode fiber 275 meters 550 meters 5 kilometers
1000base-cx coaxial cable pair 25 meters
1000base-t4 manages the Category 5 twisted pair 100m Gigabit Ethernet network. It is the same as the previously used and learned Ethernet network. It uses Gigabit Ethernet, and the backbone and network segments and desktops have been seamlessly integrated. , network management has become easier.
Advantages of Gigabit Ethernet technology:
The technology is simple, such as retaining the frame format of Ethernet, management tools and understanding of the network concept.
Easy to upgrade, smooth transition from existing traditional Ethernet and fast Ethernet to Gigabit Ethernet, without the need to master new configuration, management and troubleshooting techniques;
Online investment can be protected without the need to retrain users or invest in additional network agreements;
Gigabit Ethernet has good interoperability and backward compatibility;
The price of the connection is relatively low;
It can provide 10 times the transmission speed of Fast Ethernet.
Gigabit Ethernet vs. ATM Gigabit Ethernet atm
Although there are many standards in the standard ieee802.z, due to the complexity of the atm technology, the standard is still in progress, and it takes time to improve the bandwidth of 1000mbps155mbps or 622mbps.
Competitive ability, the number of switches submitted by manufacturers, dozens of various nic services, becoming a new growth point for technology companies. There are more than a dozen media supporting stp, utp5, multimode fiber, multimode fiber atm-622m and higher speed only Running the learning curve on the fiber, the complexity of the technology is easy to be complicated, it is difficult to learn and compatibility with existing data applications and networks without any changes. The existing lan collaboration technology is complex and inefficient.
Qos guarantees different types of new technology protocols such as rsvp, rtp, rtcp, 802.1p and a series of technologies in ip priority. In the case of lane, svcs or ietf is required to formulate complex mapping of rsvp to solve multi-vendor products. Interoperability is based on standard interconnect high-level interoperability, such as switch-to-switch signaling, and there is no guarantee that the ATM will be multi-protocol, and the standard is still improving.
Vlan's support is consistent with Fast Ethernet, but the same vlan connection and composition standards can easily cover Ethernet's fast Ethernet and Gigabit Ethernet images based on lan's release field, while atm's can Interoperability is both boring and complicated. In short, the Gigabit Ethernet network is more vital than the ATM network in the xxx area government office backbone network, and it is more affordable.
2, network technology selection conclusions In summary, in the selection of xxx area government office network technology should consider the following:
1. How to protect existing investments in the long run. An effective way to protect existing investments is to use existing network technologies and products in future network technology upgrades. Just like the speed of computer development, the development of network technology is also very rapid. If the existing technology can not be reasonably guaranteed to be used after the network upgrade in the future, it will bring great waste of funds. From the current trend, the use of Gigabit Ethernet technology is the most appropriate.
2, performance and price ratio. The performance of Ethernet, Fast Ethernet, Gigabit Ethernet and ATM is low to high, but the price is also low to high. In the construction of the xxx district government office network, we must fully consider the effective use of office funds. Choosing the applicable network technology is the key, so choosing Huawei network products is the best choice. What is currently seen is the country.

External technologies and products have virtually increased the cost of network construction, which has also brought certain obstacles to the popularity of the Internet.
3. After-sales service: The use of the government office network in the xxx area. From the past experience, the after-sales service problem is more prominent. A large number of domestic and foreign products are currently unable to achieve good pre-sales and after-sales support, and the repair time is generally 3 months to 6 months. Huawei's strong after-sales service system guarantees a 72-hour response throughout the country, and a first-tier city such as Shenyang can achieve 24-hour reverberation;
In the construction of the government office network in the xxx area, we use Huawei's switch supporting Gigabit Ethernet technology in the selection of switching equipment for the backbone and access layer.
Second, the overall structure of the network design network requirements characteristics ● Gigabit switching equipment to build the backbone, to achieve 100 megabit switching to the desktop, the backbone requires support for Layer 3 switching technology;
● It has good scalability and is convenient for network administrators to perform routine maintenance;
● Virtual subnets are divided between departments to ensure the security of data within the network and reduce the pressure on the amount of backbone data;
● Control the priority and quality of services, which can be prioritized according to specific addresses and agreements to meet the bandwidth requirements of important applications.
● Multiple routing protocol support.
● Support multipoint multicast.
●Multi-mode fiber-optic wiring is adopted outdoors, and multi-mode four-core fiber is used, which is laid by overhead wiring.
● The indoor wiring materials are selected from the five categories of non-prohibited twisted pair cables, and the wiring room position is reasonably arranged to avoid the occurrence of excessive transmission distance.
The overall structure of the network logically, the entire network can be divided into the core layer and the access layer, each layer has its own characteristics.
The advantages of hierarchical design can be summarized as follows:
Scalability: because the network can grow modularly without encountering problems;
Simplicity: By dividing the network into many small units, the overall complexity of the network is reduced, troubleshooting is easier, and the potential problems of broadcast storm propagation and routing loops can be isolated.
Design flexibility: Easily upgrade the network to the latest technology, upgrading any level of network will not affect other levels, without changing the entire environment.
Manageability: Hierarchy makes the configuration of a single device much less complex and easier to manage.
Based on the research on the structure of government office network in xxx area, combined with the user's application requirements, we designed and set up a wiring closet as the network management center of the whole system. Other buildings are connected to the core switch through Gigabit multimode or single mode fiber. Achieve redundancy of backbone links and balanced distribution of data traffic. That is, the user access layer Huawei ls-2403h switch completes the parsing and calculation of the data packet, and the switch completes the data packet forwarding in the same network segment to complete the data forwarding between different network segments vlan, the entire network data. The flow is reasonable. Through the link redundancy and device redundancy of the core layer, the data can be quickly forwarded and the link redundancy of the whole network is eliminated, and a single fault point is eliminated, thereby ensuring the security and stability of the network application.
Third, the network equipment configuration equipment selection principle Logically, the entire xxx area government office network network can be divided into the core layer, access layer, each layer has its own characteristics. Summarized as follows:
Scalability: The design ideas in the solution ensure that the network can be modularized and will not encounter problems in future network expansion. According to the design concept of the large-scale network multi-center network, the expansion of the government office network in the xxx area and the seamless upgrade of existing equipment will be guaranteed.
Simplicity: By dividing the network into many small units, the overall complexity of the network is reduced, troubleshooting is easier, and the potential for broadcast storm propagation and routing loops can be isolated.
Design flexibility: Easily upgrade the network to the latest technology, upgrading any level of network will not affect other levels, without changing the entire environment.
Manageability: Hierarchy makes the configuration of a single device much less complex and easier to manage.
Due to the large-scale development of the government office network in the xxx area, the core layer equipment needs to provide complex network applications such as multimedia office, office automation, book data retrieval, remote interconnection, and video conference. For the convenience of management, we recommend the switch. As a network to form a switching device. Choose one Huawei ls-3526 switch as the backbone switch to achieve 1000m backbone 100m to the desktop.
The ls-3526 series switches support stacking technology. In the future, the expansion of the connection is extremely flexible and convenient, without changing any configuration of the original network. By increasing the number of stacked switches or porttrunking, the network scale can be expanded; localized switching is implemented, and the entire network is improved, and the performance of the entire network is qualitatively changed. Gigabit fiber optic modules are selected and connected to the backbone to realize the Gigabit transmission of the backbone. The ls-3526 series switches support network management and stacking. It is easy to expand the number of connections by stacking as needed. In addition, the ls-3526 series switches are built on a powerful and absolutely non-blocking 32g switching backplane to ensure non-blocking wire-speed switching between all the interconnects in the stack.
In addition, the ls-35266 switch can also be installed with a 100-megabit fiber module while installing a Gigabit fiber module. It can fully adapt to the current or future fiber-optic wiring in the building, and has great flexibility.
High-reliability next-generation Ethernet switch-quidways3500/3000 series overview With the rapid development of Internet and data communication services, people's work, study and life have become more and more dependent on network and communication. The reliable operation of network equipment has become more and more closely related to people's normal production and life order. As one of the core devices of network data communication, Ethernet switch equipment, while facing more and more data processing requirements, people have also proposed to continuously enhance reliability and improve equipment. Run time requirements. For this reason, Huawei's 3com company's quidways3500/3000 series of high-performance Ethernet switches are designed with high reliability and high availability as the product. Various measures are taken through hardware and software design to provide a variety of high-reliability systems. Program.
Redundant power supply
Quidways3500/3000 series Ethernet network

The switch provides an rps power backup interface, which provides one-to-one power backup and protection for the device. It can also back up and protect multiple devices supporting the rps interface with one DC power supply.
Spanning tree
The quidways3500/3000 series Ethernet switches support the stp/rstp/mstp spanning tree protocol.
The spanning tree protocol is mainly used to establish and maintain the topology of the local area network, eliminate the network broadcast storm caused by the cyclic connection, and provide the redundant backup function of the network topology. The path that is usually used as the backup is blocked. When the network device fails, the connection status can be adjusted in time to adjust the network topology.
The working principle of the spanning tree protocol: The bridging device in the network determines that the highest priority device is the root bridge of the network according to the set priority value and the mac address, and the root bridge periodically transmits configbpdu packets, each receiving the packet. The switch updates the packet content to other connections according to its configuration and network topology. When a switch receives configbpdu from two or more connections, it indicates that the network is in the network. There is a loop, and one of the connections is reserved for forwarding, and the remaining connections are set to be blocked.
In addition to supporting traditional spanning tree protocols, the quidways3500/3000 series Ethernet switches support the ieee802.1w Rapid Spanning Tree Protocol and the 802.1s Multiple Spanning Tree Protocol. The Rapid Spanning Tree Protocol is an improvement of the Spanning Tree Protocol, which improves the performance of network protection based on the original functionality. The traditional spanning tree switching time is 42s. It takes at least 30 seconds to discover link breaks, data interruptions, and data recovery. The fast spanning tree protocol can switch data streams to the backup chain in only 6-8 seconds. On the road.
The 802.1s multiple spanning tree protocol can support multiple spanning trees within a network, allowing administrators to assign vlan traffic to a unique path. By assigning a separate spanning tree topology to the vlan, the network administrator can ensure that both vlans can be transmitted smoothly over the network. This can balance network traffic and improve reliability. The quidways3500/3000 series Ethernet switches can support up to 17 or 33 stp instances.
Link Aggregation In order to obtain higher data transmission bandwidth on the Ethernet, the quidways3500/3000 series Ethernet switches provide Layer 2 connectivity and link aggregation. Thus, in the spanning tree agreement and other Layer 2 agreements, all physical connections made by link aggregation are treated as the same connection. Redundancy backup and load sharing can be performed between the link aggregations.
In actual application, the connection 进行 that is aggregated is equivalent to a connection 埠. Any packet forwarded to the aggregated connection will be distributed to different connections through the logical operation of the source and destination addresses. on. Even multicast and broadcast messages are not duplicated, and traffic is balanced across different connections by logically calculating the address. The quidways3500/3000 series Ethernet switch system monitors the new addresses of hardware table misses at Layer 2 and Layer 3. If the new address is on the aggregated connection, the logical calculation is performed using the mac address or the ip address according to the difference between the second and third layers. According to the result of the logic, the corresponding connection is selected as the forwarding connection, and sent to the network. The frame of the destination address will be forwarded according to the result of load balancing, which implements load balancing and redundancy protection between the ports, ensuring that the data flow does not appear out of order.
Vrrp redundant backup
The quidways3500 series Ethernet routing switch supports the vrrp redundancy backup protocol. Vrrp is called virtualrouterredundencyprotocol. In simple terms, vrrp is a fault-tolerant protocol that ensures that when the next-hop router of the host fails, it can be replaced by another router in time to maintain communication continuity and reliability. Usually, a preset route is set on the host, and the next hop points to a router, so that the host communicates with the external network, but when the host's default router fails, the host cannot communicate with the external network. After starting vrrp, the IP address of the host's default router is actually the IP address of a vrrp virtual router. The vrrp virtual router consists of a primary router and one or several backup routers, and the primary router implements true forwarding. When the primary router fails, the backup router automatically elects the program and selects a new primary router to forward Layer 3 traffic. With the proper vrrp network configuration, the quidways3500 series Ethernet routing switch can also implement the load balancing function of Layer 3 traffic while implementing route fault backup. The quidways3500 series Ethernet routing switch supports up to 256 sets of vrrp virtual routers.
During normal operation, the two routing switches are hot backups to achieve equal traffic distribution. In the event of a fault, the backup routing switch becomes the master and all traffic is routed to the routing switch.
Equivalent routing In addition to supporting the Layer 3 forwarding fault-tolerant protocol vrrp from the device level, the quidways3500 series Ethernet routing switch also supports equal-cost routing. If the device supports the equal-cost route, the Layer 3 forwarding traffic destined for the destination ip or the destination network segment can pass through the same destination ip or the destination network segment. Different paths are shared to implement network load balancing. When some of the paths fail, the other paths replace the forwarding processing to implement the route redundancy backup function.
Supporting equal-cost routing not only from software but also from hardware is a significant advantage of the quidways3500 series of Ethernet routing switches compared to similar products in the industry. In the past, some routing switches also claimed to support equal-cost routing, but they only supported the software. The packets forwarded by the software can use equal-cost routes. However, for packets directly forwarded by hardware, they can only be fixed from one. Path forwarding. The quidways3500 series Ethernet router also implements equal-cost routing support from the hardware, realizing load balancing and routing redundancy backup of hardware Layer 3 forwarding traffic.
The quidways3500 series Ethernet switch supports up to four equal-cost routes, and regardless of the routes generated by routing protocols such as rip and ospf, or statically configured routes, whether it is network segment routing, host routing, or even preset routes, it can support. Price routing.
The quidways3500 series Ethernet routing switch can guarantee the order of packets while supporting equal-cost routing and load balancing. By calculating the destination ip address and source ip address of the data stream, the quidways3500 series Ethernet routing switch can ensure that the same ip forwarding stream is forwarded from the same routing path, thus ensuring the routing report of the entire end-to-end network. The order of text forwarding avoids the occurrence of tcp global synchronization and other issues.
Policy routing
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Nbsp;quidways3500 series Ethernet routing switches support high performance policy routing. Policy routing is a routing extension function that is being supported by more and more routers or Layer 3 switch devices. Devices that support policy routing can not only use the destination IP address of the packet as the basis for routing, but also the packet. The source IP address, the source mac address, the connection line of the message filial piety message, the packet type, the vlan attribute of the message, and other extended conditions are selected to select the route. Through reasonable routing policy design, network traffic load balancing can be realized, routing devices can be fully utilized, and redundant backup functions between routing and switching devices can be realized. At the same time, various service levels can be distinguished to provide different users. Qos service. Policy routing is set on the receiving message interface instead of the transport interface. The quidways3500 series Ethernet routing switch can support the policy routing function well, and can redirect the next hop of the route to a physical connection, or a next hop IP address.
The following figure shows the networking example of the quidways3500 series Ethernet routing switch that supports policy routing. The user network has two peer-to-peer quidways3500 series Ethernet routing switch devices. The main functions of the two devices are different. One main user is responsible for various server access requirements within the user's private network. As an outlet to access the internet. With the appropriate routing policy configuration, different routing devices are specified according to the source or destination IP address policy, and different access channels are selected, so that the network traffic is forwarded according to the standards set by the network administrator. And the route backup function of the policy route can smoothly switch the traffic to another device when a device fails, ensuring the uninterrupted service of the user accessing the internal server and the external website.