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Reading the following, <br />
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'Ethernet network is a shared environment so all devices have the right to access to the medium. If more than one device transmits simultaneously, the signals collide and can not reach the destination. <br />
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If a device detects another device is sending, it will wait for a specified amount of time before attempting to transmit. <br />
When there is no traffic detected, &nbsp;a device will transmit its message. While this transmission is occuring, the device continues to listen for traffic or collisions on the LAN. After the message is sent, the device returns to its default listening mode. '<br />
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Isn't this true for an LAN with only hubs? With switch, each port at switch device has a separate collision domain. If then, I think multiple devices connected to switch can transmit frames at the same time and switch handles the collision avoidance.
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Reading the following, 

'Ethernet network is a shared environment so all devices have the right to access to the medium. If more than one device transmits simultaneously, the signals collide and can not reach the destination. 

If a device detects another device is sending, it will wait for a specified amount of time before attempting to transmit. 
When there is no traffic detected,  a device will transmit its message. While this transmission is occuring, the device continues to listen for traffic or collisions on the LAN. After the message is sent, the device returns to its default listening mode. '

Isn't this true for an LAN with only hubs? With switch, each port at switch device has a separate collision domain. If then, I think multiple devices connected to switch can transmit frames at the same time and switch handles the collision avoidance.

CCNA understanding Ethernet and CSMA/CD

Reading the following, 

&#39;Ethernet network is a shared environment so all devices have the right to access to the medium. If more than one device transmits simultaneously, the signals collide and can not reach the destination. 

If a device detects another device is sending, it will wait for a specified amount of time before attempting to transmit. 
When there is no traffic detected,  a device will transmit its message. While this transmission is occuring, the device continues to listen for traffic or collisions on the LAN. After the message is sent, the device returns to its default listening mode. &#39;

Isn&#39;t this true for an LAN with only hubs? With switch, each port at switch device has a separate collision domain. If then, I think multiple devices connected to switch can transmit frames at the same time and switch handles the collision avoidance.

A switch is a device that filters and forwards packets of data between LAN segments. Switches operate at the data link layer or the network layer of the Open Systems Interconnection (OSI) Reference Model and therefore support any packet protocol. LANs that use switches to join segments are called switched LANs or, in the case of Ethernet networks, switched Ethernet LANs. A hub is a connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports; when a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

Switches / Hubs

A router is a networking device that forwards data packets between computer networks. Routers perform the "traffic directing" functions on the Internet. The most familiar type of routers are home and small office cable or DSL routers that simply pass data, such as web pages, email, IM, and videos between computers and the Internet. More sophisticated routers, such as enterprise routers, connect large business or ISP networks up to the powerful core routers that forward data at high speed along the optical fiber lines of the Internet backbone. Though routers are typically dedicated hardware devices, use of software-based routers has grown increasingly common.

Routers

Networking hardware includes the physical devices facilitating the use of a computer network. Typically, networking hardware includes gateways, routers, network bridges, modems, wireless access points, networking cables, line drivers, switches, hubs, and repeaters. But it also includes hybrid network devices such as multilayer switches, protocol converters, bridge routers, proxy servers, firewalls, network address translators, multiplexers, network interface controllers, wireless network interface controllers, ISDN terminal adapters and other related hardware.