CCNA

10GBASE-ER Maximum cable length

30km

10GBASE-LR Maximum cable length

10km

10GBASE-SR Maximum cable length

400 meters

10GBASE-SR, 10GBASE-LR, and 10GBASE-ER were defined in the IEEE [..] standard

802.3ae

IEEE Standard […] = 1 Gbps Ethernet (1000BASE-T)

802.3ab

IEEE Standard […] = 10 Gbps Ethernet (10GBASE-T)

802.3an

IEEE Standard […] = 10 Mbps Ethernet (10BASE-T)

802.3i

IEEE Standard […] = 100 Mbps Ethernet (100BASE-T)

802.3u

What is the numeric range of the first octet of a class A IPv4 Address?

0-127

What is the numeric range of the first octet of a class B IPv4 address?

128-191

What is the numeric range of the first octet of a Class C IPv4 address?

192-223

What is the numeric range of the first octet of a Class D IPv4 address?

224-239

What is the numeric range of the first octet of a Class E IPv4 address?

240-255

1000BASE-LX maximum cable length

550 meters (multimode)

5 kilometers (single-mode)

1000BASE-LX was defined in the IEEE [...] standard.

802.3z

Standard STP (NOT PVST) BPDUs are sent to destination MAC address

0180.c200.0000

spanning-treee vlan vlan-id root primary sets the STP priority to [...], or 4096 less than the current root's priority.

24576

spanning-tree vlan vlan-id root secondary sets the STP priority to [...]

28672

PVST+ BPDUs are sent to destination MAC address:

0100.0ccc.cccd