OSPF Protocol application and algorithm optimization in Communication Networks

3G communication technology has been widely used and is evolving to 4G. The number of access stations and transmission points in the communication network has increased exponentially, and there is still a rapid growth trend. The communication network's site network capabilities and local fault recovery protection mechanisms have also become more demanding. The Open Shortest Path priority (0SPF) is a type of dynamic routing selection protocol. It can quickly check the topology changes of the running network and quickly compress new routes without loops, short time and small data streams have become the best choice for modern communication networks.

1 concepts related to communication networks and OSPF

1.1 concepts related to communication networks

Traditional communication networks, that is, telephone exchange networks, are composed of exchange, transmission, and terminals. Exchange refers to the information exchange intermediary, transmission refers to the information transmission media, and terminal refers to users' mobile phones, phones, computers and fax machines. Modern communication networks are the total number of communication-related services that professional organizations provide to society, enterprises, and individuals by working procedures and communication equipment .... The Internet is a new communication network. its normal operation requires a series of network protocols.

1.2 concept of OSPF

OSPF (0pen Shonest Path FirSt Open Shortest Path FirSt) is an Internal Gateway Protocol (IGP) used in a single autonomous system () decision routing. It implements the routing protocol for the link status, which is an internal gateway protocol (IGP). Therefore, it operates within the autonomous system.

2. OSPF Protocol application in Communication Networks

The networking of a typical communication network. Each site in the communication network uses the 0SPF protocol to form a hierarchical networking. Based on the actual situation, the backbone domain can be connected to the network management terminal of the data center through an Ethernet line. Or connect to the LAN and a 2 Mbit/s circuit to connect to the network management terminal to form a multi-channel protection management channel. Generally, the above connection methods will be used in combination.

In optical communication networks, site connections in various regions related to the OSPF protocol usually use broadcast topology and point-to-point topology. After the OSPF protocol is enabled for sites in the same region, you must manually configure the Domain value and IP address of each port and initialize the internal parameters of the Protocol, then, it discovers and connects neighbors and starts link state information interaction. At the same time, each site in the domain needs to perform regular network topology detection and updates. After network convergence is completed, all sites in the same domain have databases with the same information, and build their own Shortest Path Tree Based on Information calculation. The route table is automatically generated based on the shortest path tree.

3. Communication NetworkOSPFProtocol Algorithm Optimization

In general, the communication network will first plan the network topology, manually configure the site, and start commissioning to network supervision .... The planning focus of the network topology refers to the layout of the backbone network. The subordinate network is usually dynamically expanded with the business. In a hierarchical network that uses the OSPF protocol, the number of access network sites is usually dozens of times that of the backbone network. When the network is being established, the number of backbone networks in the early stage is small, and the number of O & M personnel is relatively large. After Non-backbone sites are established in the later stage, the workload will multiply, O & M personnel will be unable to ensure the normal and high-quality operation of the network. Therefore, the standardization and simplification of the start-up process have been widely valued by operators and equipment manufacturers.

After the backbone network is planned, the algorithm of the OSPF Protocol needs to be initialized and optimized to enable the access of sites in non-backbone regions to automatically distribute the correct Domain value and IP address, and ensures real-time monitoring and identification of network management.

3.1 optimizing the HeIIo protocol and overall solution in the OSPF Communication Network

In communication networks using OSPF, the establishment, maintenance, and correct two-way communication of neighbors require the use of the Hello protocol. After the underlying physical channel is built, the site sends a Hello packet to the multicast address to dynamically obtain the neighboring site. After receiving the correct Hello packet, add the information in the packet to your Hello packet. If both packets contain the information of the other site, the channel status changes to 2-way, indicates that the neighbor is successfully created. The algorithm optimization of OSPF is based on neighbor creation.

Websites in non-backbone domains are not configured correctly. You need to add new configuration requests and accept packages based on the Hello protocol and run them in the neighbor Down state, after correctly configuring the connection between the vro and the boundary, the vro is automatically and correctly divided into the completed Domain value and the site IP address, and the vro with the boundary is reported to the network management for supervision.

To optimize the overall scheme of the Hello protocol, you must first correctly configure the network site of the backbone domain. If no site is correctly configured for a non-backbone domain, you can only send and receive Hello packets after the network is connected, without establishing a neighbor, the neighbor site is in the Down state. After receiving the request packet configured for the connection site, it forwards the packet to the site of the border router. The error Hello message is discarded. If the site is not correctly configured for the connected site, the package will also be discarded and will not be forwarded.

The site allocation and management of the VBR's non-backbone domain IP information table. After determining the request package, the region value and IP information are allocated. Connect to the site to receive the configured response packet and then forward the requested site. After receiving the configuration response packet of the requested site, enable the correct configuration to access the site and establish a normal OSPF protocol and a neighbor.

3.2 site operation process optimization

For sites in non-backbone domains, you need to add configuration for the request and response mechanisms to obtain the correct Domain value and IP information. For the sites of the border router, the algorithm mechanism needs to be increased to complete maintenance and allocation of domain values and IP addresses.

When optimizing the site of the border router, you need to increase the allocation algorithm mechanism of the lP table to ensure the continuity of the IP table and improve the search efficiency) the establishment of the buffer pool for multi-site application package processing at the same time. You also need to record and allocate IP Tables, and regularly maintain non-backbone domain IP Tables to collect and refresh site lP information, enables the IP value to be used cyclically. The website information of non-backbone domains needs to be dynamically reported to the support function of the network management, so that the network management can dynamically monitor and identify.

To sum up, with the rapid development of network communication, the application of OSPF protocol networking in the communication network is increasingly important. The OSPF protocol can discover the network topology of the Communication site and establish the network based on the actual communication network, the Algorithm Improvement and optimization of the OSPF protocol can save the planning and configuration of the area and IP address information of the network construction site in non-backbone domains, and implement automatic access supervision of the network management more efficiently and correctly. As the scale of the communication network expands, the improvement and optimization of OSPF protocol is of great significance to the development of the communication network.