MAC ADDRESS LEARNING SERIES
MAC ADDRESS LEARNING MAC

The switch doesn't use ARP, but ARP can help in preventing this situation from occurring in the first place, for two reasons: This is often confused because the end effect is the same, but they are actually different.

MAC ADDRESS LEARNING MAC

A broadcast is simply a frame with a destination MAC address of. A switch never broadcasts frames, a broadcast is not an action a switch can take. One last note regarding the terms Flooding vs Broadcast.

MAC ADDRESS LEARNING SERIES

I would also suggest reading the entire article series for a closer look at how a packet moves through a network. You can read more about how a Switch works here (where I took the animation from). Hopefully, upon receiving the frame, Host B will generate a response frame, which will allow the Switch to learn the MAC address mapping from the return frame. This assures that if host B exists (which at this point, the switch does not know yet), that it will receive it. Since it doesn't know where the destination MAC address is, it floods the frame out all ports. Upon receiving the frame, it records Host A's MAC Address to Switch Port mapping.

When Host A sends the frame, the switch does not have anything in its MAC address table. S1(config-if)# switchport port-security mac-address sticky S1(config-if)# switchport port-security mac-address aaaa.bbbb.1234 S1(config-if)# switchport port-security maximum 2 *Mar 1 00:12:39.194: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to upĮnter configuration commands, one per line. *Mar 1 00:12:38.179: %LINK-3-UPDOWN: Interface FastEthernet0/1, changed state to up Use the show port-security interface and the show port-security address command to verify the configuration. The administrator specifies a maximum of 2 MAC addresses, manually configures one secure MAC address, and then configures the port to dynamically learn additional secure MAC addresses up to the 2 secure MAC address maximum. The following example demonstrates a complete port security configuration for FastEthernet 0/1 with a host connected to port Fa0/1. Saving the running configuration will commit the dynamically learned MAC address to NVRAM. The administrator can enable the switch to dynamically learn the MAC address and “stick” them to the running configuration by using the following command: Switch(config-if)# switchport port-security mac-address sticky If the switch is rebooted, the port will have to re-learn the device’s MAC address. When the switchport port-security command is entered, the current source MAC for the device connected to the port is automatically secured but is not added to the startup configuration. The administrator manually configures a static MAC address(es) by using the following command for each secure MAC address on the port: Switch(config-if)# switchport port-security mac-address mac-address The switch can be configured to learn about MAC addresses on a secure port in one of three ways: S1(config-if)# switchport port-security maximum S1(config-if)# switchport port-security maximum ? The maximum number of secure MAC addresses that can be configured depends the switch and the IOS. To set the maximum number of MAC addresses allowed on a port, use the following command: Switch(config-if)# switchport port-security maximum value Mati ur Rehman on What is Inter-VLAN Routing?.What is the data plane DP in SDN? - Question And Answers Area on Control Plane and Data Plane.

Transport Layer Responsibilities May 21, 2021.Network Virtualization Technologies September 19, 2021.Core Components of ACI September 19, 2021.Device Discovery with LLDP October 10, 2021.Channel Management | WLAN October 17, 2021.Switchport Security Configuration June 12, 2022.Understanding VLAN Trunk Protocol (VTP) June 12, 2022.RIP Characteristics and RIP Timers June 12, 2022.

Dynamic Trunking Protocol (DTP) June 12, 2022.

Troubleshooting VLANs and Trunks June 12, 2022.

Distance Vector Protocols July 16, 2022.

Mac address learning