What is a network Bridge, What is a network Switch
A Bridge/Switch is a network device that typically operates at the Data Link layer (Layer 2) of the OSI model.
Before reading further, I strongly recommend you to read following lessons thoroughly and understand the core concepts of computer networking.
• Types of network communication - Unicast, Multicast and Broadcast
• Collision domain and broadcast domain
• Seven Layers of OSI Model.
• Comparison between TCP/IP and OSI
• IP addresses, subnet mask, network addresses
• MAC addresses
A bridge or switch performs its job by examining the Data Link Layer (Layer 2) data packet (Ethernet Frame) and forwarding the packet to other network devices based on Layer 2 addresses (MAC Addresses). Both switches and bridges function using Datalink Layer (Layer 2) addressing system (also known as MAC addresses), to forward Ethernet frames from one device to another device in an Ethernet standard based LAN (Local Area Network).
Each port of a network switch is in a separate collision domain and therefore switches are used to divide a big collision domain into multiple smaller collision domains.
Bridge has only few ports and connect only a few collision domains, or Hosts. A bridge has comparatively less ports than a switch. Network switches with 24 ports or 48 ports are usually available in the market. Brides and switches are considered to operate at the Data Link Layer (Layer 2) of the OSI model.
Click the following link to learn differences between Bridges and Switches.
The term "Bridge" is not much used in networking industry these days. So, use the term "Switch" instead of "Bridge".
Ethernet network switches are designed to operate using Twisted pair cabling and use RJ45 jack to connect different network devices. Fiber optic ports in Ethernet switches are normally used to connect two different Ethernet switches together.
Following picture shows a Cisco 24 Port 10GBase-T (10 Gigabits per second) Ethernet Switch. For more details and technical specifications, please visit official Cisco product page for Cisco SG350XG-24T 24-Port 10GBase-T Stackable Managed Switch.
