What is Ring Topology : Working & Its Applications

The arrangement of network that includes nodes as well as connecting lines between sender and receiver is known as network topology, which plays a key role in how a network works. A network functionality mainly depends on the topology. There are different types of network topologies available and each type of topology has its own structures, functionality, and its applications. But selecting the correct topology can help in increasing network performance & maintain network topology enhancing data transfer rates & energy efficiency. This article discusses one of the types of network topologies like ring topology – working with applications.

What is Ring Topology?

Ring topology definition is; a type of network topology in which every device is simply connected to two additional devices on any side using a coaxial or an RJ-45 cable to form a circular ring with connected devices. In this type of topology, the transmission of data can be done in single direction along the ring which is called as a unidirectional ring. So, the data is transmitted from one device to another until it reaches the destination.

How Does Ring Topology Work?

In a ring topology, every device is simply connected with two devices in a circular form. In this type of topology, the data is transmitted from one device to another until the data attains its destination. The data from the transmitting node to the destination is transmitted by using tokens. So this topology is also called token ring topology.

This topology commands all the nodes within the network to stay active for data transmission so it is also known as active topology. If the no. of nodes within the network is large, then tokens have to jump several nodes before attaining their destination, and there could be a loss of data. To avoid this loss of data, repeaters are installed to enhance the strength of signal.

In ring topology, the data transmission between different nodes includes the following step.

• The empty tokens on the ring are circulated freely from 16Mbps speed to up to 100Mbps.
• This token includes placeholders for storing data frames and also holding the address of the sender or receiver.
• If a transmitting node wishes to send a message, then it takes a token & packs it with the data, MAC address of receiving node & its own ID in the equivalent spaces of the token.
• This filled token is transmitted to the next node within the ring. After that, this next node gets the token & checks whether the data transmitted is copied from the frame toward the node & the token is set to zero & transmitted to the next node, or the token is transmitted to the next node as it is.
• The previous step is continued until the data attains the correct destination.
• Once the token arrives at the sender, it discovers that the receiver has read the data then it will separate the message.
• The token is reused & ready to be used by any one of the nodes in the network.
• If a node is stationary within the path of the ring network & the communication is broken down & the network simply supports a dual ring then data is transmitted in the reverse direction toward the destination.

Protocols in Ring Topology

The popular protocols used in ring topology are Resilient Ethernet Protocol (REP) and Device Level Ring (DLR) & Media Redundancy Protocol which are discussed below.

Resilient Ethernet Protocol

REP is a ring topology protocol used to provide an approach to handle failures, control loops and help in increasing convergence time normally 15ms. This ring protocol is mainly used between switches only. In addition, several REP rings can also exist over a switch. This REP ring is simply arranged by allocating particular roles of ports on the switch like Primary, No-neighbor, Edge, Transit, and No-neighbor Primary.

Device Level Ring

The device level ring is one type of ring protocol that is utilized by current Rockwell Automation devices like Ethernet/IP communication adapters, PowerFlex Drives, CompactLogix® Controllers, Stratix® switches & ControlLogix.

This protocol simply allows automation devices to be arranged within a ring through a junction time of below 3ms. This protocol is very simple to set up and you need to assign a ring supervisor only to connect the ring. So, the supervisor of the ring simply observes the ring to check the faults.

Media Redundancy Protocol

Media Redundancy Protocol is used in a Ring topology to keep away from single points of breakdown by providing 10ms or below recovery time, load balancing & fault-tolerance. The way media redundancy protocol works; a ring manager switch will block all the transmitting packets on one of its two selected ring ports to split the switch loop. The traffic from connected devices to the switches within the loop will still have a lane to each other including redundant links except exclusive of the harmful switch loop.

Features

The features of ring topology include the following.

• In this topology, no. of repeaters are utilized.
• The data transmission is unidirectional.
• The data in this topology is transmitted in a sequential way bit by bit.
• It improves communication link fidelity. If a single link breaks, then the other is prepared for communication.
• It is extremely reliable for long-distance communication because every node within the network functions like a repeater. So, the signal doesn’t drop its strength.
• In this topology, an in-built acknowledgment device is obtainable & it is released simply once the network completes its communication.
• The utilization of tokens in this network will prohibit the possibility of collisions or cross-communication because simply a single device has network charge & two devices are simply allowed to communicate at the same time.

Difference between Ring Topology, Bus Topology, and Star Topology

The differences between ring, bus & star topology include the following.

Characteristics

The characteristics of ring topology include the following.

• In this topology, if one computer is down then the entire network will be down.
• If the main cable in the network is down then the whole network will be down.
• Single computer can transmit data at a time due to token.
• Maximum computers within the network can affect the entire network because when computers in the network increase then the network will be slow.

Advantages and Disadvantages

The advantages of ring topology include the following.

• The data in this topology transfers in a single direction, so it reduces packet collision.
• A network server is not required for controlling network connectivity.
• A number of devices can be connected without affecting the performance of the network.
• Easy to recognize & separate single points of failure.
• There is no requirement for a server for controlling the connectivity between the nodes within the topology.
• This topology is very cheap to install & also expand.
• The data transfer speed is high.
• Every computer in this topology has equivalent access to resources.
• Fault recognition is simple.
• As compared to the bus topology, the performance of this topology is better in heavy traffic because of the presence of tokens.

The disadvantages of ring topology include the following.

• This type of topology is expensive.
• As compared to the bus topology, the performance of this topology is slow.
• Troubleshooting is difficult.
• These topologies are not scalable.
• It depends on a single cable.
• The whole network will go down if a node goes down.
• A token or data packet must pass throughout all the nodes due to the Uni-directional ring,
• Adding & removing any node in a network is very difficult & also it causes an issue within network activity.

Ring Topology Applications/Uses

The applications of ring topology include the following.

• This topology is used in the local area network and wide area networks.
• This type of topology is frequently used in the telecommunication industry and is commonly used in SONET fiber networks.
• It is used as a backup system in various companies for their existing network.
• Once the connection is misplaced through a node, and then it uses the bidirectional capacity to route traffic in one more way.
• It is applicable in educational institutions.

Thus, this is all about an overview of a ring topology – working with applications. The ring topology examples are; SONET (stands for Synchronous Optical Network) ring network, as a backup system in many organizations for their existing network, etc. Here is a question for you, what is star topology?