Switches
Switches
Network switches are essential networking devices that operate at the Data Link Layer of the TCP/IP model.
They allow multiple computers to connect to a network through a single node and therefore reduce the wiring requirement. This is especially important in larger networks.
They are designed to efficiently manage data traffic within local area networks (LANs) by intelligently forwarding data frames based on MAC (Media Access Control) addresses.
How Switches Work
Switches use a MAC address table. The table maps MAC addresses to switch ports.
When a frame arrives:
- The switch reads the destination MAC.
- Looks it up in the MAC table.
- Sends the frame only out the port corresponding to that MAC.
- If the MAC isnβt in the table yet, the switch floods the frame to all ports except the incoming one.
MAC Addresses
Media Access Control (MAC) addresses, are unique identifiers assigned to network interfaces in computing devices. They operate at the Data Link Layer (Layer 2) of the OSI model.
MAC address is 48 bits in length, typically represented as 12 hexadecimal digits (0-9 and A-F) grouped into pairs, separated by colons or hyphens. For example, a MAC address might look like "00:1A:2B:3C:4D:5E."
Each MAC address is globally unique. This means that no two network interfaces in the world should have the same MAC address.
- The first 24 bits (the first three pairs of hexadecimal digits) of a MAC address represent the OUI, which identifies the manufacturer or organization that produced the network interface card (NIC).
- The remaining 24 bits are used to uniquely identify the specific NIC within that manufacturer's allocation.
MAC table
A MAC address table is a critical component within network switches. It is used to store and manage MAC (Media Access Control) addresses and their associated network interfaces.
When a switch receives a data frame from a device on one of its ports, it examines the source MAC address in the Ethernet frame header.
The switch records this MAC address and associates it with the port through which the frame was received. This process is known as MAC address learning. As more devices communicate with the switch, it continues to build its MAC address table.
What does a MAC address uniquely identify in a network?
Which type of cable is commonly used to connect devices to a network switch?
Review: Fill in the Blanks
A MAC address table is a critical component within network switches. It is used to store and manage MAC (Media Access Control) addresses and their associated . When a switch receives a data frame from a device on one of its ports, it examines the in the Ethernet frame header. The switch records this MAC address and associates it with the port through which the frame was received. This process is known as MAC address .
Media Access Control (MAC) addresses are unique identifiers assigned to network in computing devices. They operate at the Data Link Layer (Layer 2) of the OSI model. A MAC address is , typically represented as 12 hexadecimal digits (0-9 and A-F) grouped into pairs, separated by colons or hyphens. Each MAC address is globally . This means that no two network interfaces in the world should have the same MAC address. The first 24 bits of a MAC address represent the OUI, which identifies the or organization that produced the network interface card (NIC).
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Switch
- Switches
- How Switches Work
- MAC Addresses
- MAC table