Collision
Collision Definition
A collision in computer networks occurs when multiple devices attempt to transmit data over the same channel simultaneously. This causes their signals to interfere with each other, making them harder to read. The area of the network (network segment) where a device’s signals can cause collisions is called the “collision domain.”
Collisions are uncommon in modern networks, since both wired and wireless systems can usually deal with them without disruption. They’re more likely to happen on Wi-Fi networks, where all connected devices use the same channel. However, modern Wi-Fi uses collision avoidance (CA) to check channels for traffic before sending data. Collisions can also happen on wired networks, like Ethernet, though they usually occur only on older systems or when a faulty device is connected.
What Happens After a Collision?
Wired and wireless networks deal with collisions differently. Modern Ethernet uses switching that manages network traffic so device signals don’t mix. On older networks, a device that detects a collision stops transmitting, sends a jam signal to notify other devices, waits briefly, then attempts a retransmission.
On Wi-Fi, devices don’t detect collisions directly. Instead, they use an acknowledgement signal to confirm they received a signal properly. If no acknowledgement is received, the sender waits a short time before transmitting data again.
A few collisions are generally acceptable for most networks, but a high collision rate can slow performance. Repeated collisions waste resources, corrupt data packets that must be retransmitted, and can cause serious network congestion, sometimes making the network unusable.
Causes of Collisions in Computer Networks
- Simultaneous transmissions: Multiple devices sending data at the same time on the same medium, like the same Wi-Fi channel, increase the risk of collision.
- Network traffic: High traffic on a network segment can make collisions more likely.
- Hardware malfunction: Faulty cables or device issues can delay signals and cause collisions.
Read More
FAQ
There are several factors that cause collisions, including faulty equipment or an overloaded network. All these points make it more likely that two signals will try to transmit at the same time and collide.
A collision domain is the part of a network (a network segment) where several devices transmit signals and need to take turns to avoid collisions. For example, a Wi-Fi network, including a router and all connected devices, is the collision domain for all those devices.
Collisions reduce network performance because they force devices to stop sending data, wait a short time, and then try to retransmit the signals. This increases delays and wastes network resources since devices have to keep sending the same data over and over again.
45-Day Money-Back Guarantee