LAN Switching - Ethernet Basics

johnny_jiang

                                1. Cisco switches disable auto-negotiation after the speed and duplex have been configured. The other switch attempts auto-negotiation and fails.
However, the unconfigured switch can detect the speed even without auto-negotiation. By default, 10-Mbps and 100-Mbps ports use half duplex when they are unable to auto-negotiate a duplex setting.
2. Each switch has a range of reserved MAC addresses, with the first MAC being used by the switch IP address, and the rest being assigned in sequence to the switch interfaces – note 0xcd (last byte of 2nd address in the table above) is for Switch4’s FA 0/13 interface, and is 13 (decimal) larger than Switch4’s base MAC address.
VLAN 1:
IP Address 10.1.1.4
R4 MAC Address 000f.2343.87c0
fa0/13:
000f.2343.87cd
               
               
               
               

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