Vtp Objectives
Explain the role of redundancy in a converged network.
Summarize how STP works to eliminate Layer 2 loops in a converged network.
Explain how the STP algorithm uses three steps to converge on a loop-free topology.
Implement rapid PVST+ in a LAN to prevent loops between redundant switches.
Hierarchical design model addresses issues found in flat model networks. One of these issues is redundancy. Having multiple paths for data to travel the network allows for a single path to be disrupted without impacting the devices connectivity to the network. With multiple paths on a network between two devices a layer 2 loop can occur because Ethernet frames do not have ttl. A broadcast storm can occur with so many broadcasts frames are caught in a loop and are using up all available bandwidth. When this occurs the network becomes unavailable for data communications.
STP ensures that there is only one logical path between destinations on a network by blocking redundant paths. A port is blocked when network traffic cannot enter or leave that port. STA will designate a single switch as the root bridge and use that switch as a reference point for all path calculations. Each switch uses the STA to determine which port to block. STA determines which paths are to be left open by labeling distinct port roles. Elects the Root ports, designated ports and non-designated ports.
Rapid PVST+ adds vlan support to RSTP and is the preferred STP on a Cisco network. To turn this feature on use the following commands:
Switch#conf t
Switch(config-if)# spanning-tree mode rapid-pvst
Switch(config-if)#interface(#)
Switch(config-if)# spanning-tree link-type point-to-point
Summarize how STP works to eliminate Layer 2 loops in a converged network.
Explain how the STP algorithm uses three steps to converge on a loop-free topology.
Implement rapid PVST+ in a LAN to prevent loops between redundant switches.
Hierarchical design model addresses issues found in flat model networks. One of these issues is redundancy. Having multiple paths for data to travel the network allows for a single path to be disrupted without impacting the devices connectivity to the network. With multiple paths on a network between two devices a layer 2 loop can occur because Ethernet frames do not have ttl. A broadcast storm can occur with so many broadcasts frames are caught in a loop and are using up all available bandwidth. When this occurs the network becomes unavailable for data communications.
STP ensures that there is only one logical path between destinations on a network by blocking redundant paths. A port is blocked when network traffic cannot enter or leave that port. STA will designate a single switch as the root bridge and use that switch as a reference point for all path calculations. Each switch uses the STA to determine which port to block. STA determines which paths are to be left open by labeling distinct port roles. Elects the Root ports, designated ports and non-designated ports.
Rapid PVST+ adds vlan support to RSTP and is the preferred STP on a Cisco network. To turn this feature on use the following commands:
Switch#conf t
Switch(config-if)# spanning-tree mode rapid-pvst
Switch(config-if)#interface(#)
Switch(config-if)# spanning-tree link-type point-to-point