ring topology
Ring topology (English:) The ring structure is used more in LAN. The transmission medium in this structure goes from one end user to another until all end users are connected into a ring. Data is transmitted between nodes along one direction in the ring, and information is passed from one node to another. This structure obviously eliminates the dependence on the central system for end-user communication.
Image showing ring network layout
Advantages of ring structure
- The functions that can be realized are the simplest, and can only be regarded as a general file service mode;
- Faster transmission speed;
- Each end user is connected to two adjacent end users, so there is a point-to-point link, but it always operates in a one-way manner, so it is called an upstream end user and a downstream end user;
- The information flow in the network flows along a fixed direction, and there is only one road between two nodes, so the control of path selection is simplified;
- Each node on the ring is controlled by bootstrapping, so the control software is simple;
- It is suitable to use optical fiber, the transmission distance is long, and the transmission delay is determined.
shortcoming
- Response delay: Since the information source passes through each node serially in the ring, when there are too many nodes in the ring, it will inevitably affect the information transmission rate and prolong the response time of the network;
- Poor expansion performance: The closed nature of the ring structure determines that its expansion performance is far inferior to that of the star structure. If you want to add or move nodes, you must interrupt the entire network and connect with connectors at both ends of the ring;
- Difficult maintenance: The nodes of the entire network are directly connected in series, and any node failure will cause the entire network to be interrupted and paralyzed, and maintenance is very inconvenient;
- Difficult to maintain: The coaxial cable adopts the pin-type contact method, which is easy to cause poor contact and network interruption, and it is difficult to locate the fault of the branch node.
Applications
- LAN, environment with high real-time requirements
The most famous ring topology network is Token Ring