SPANNING TREE OVERVIEW
TYPES OF STP
MULTIPLE SPANNING-TREE (802.1S)
UPTO 15 INSTANCES SUPPORTED ON EVERY SWITCH
1 INSTANCE OF STP FOR A GROUP OF VLANs
RAPID PER-VLAN SPANNING-TREE(RPVST)
RAPID SPANNING-TREE (802.1W)
PORT TYPES
POINT TO POINT PORT
HALF-DUPLEX ON SHARED MEDIA
DESIGNATED PORT
ROOT PORT
EDGE PORT
NO LONGER EDGE WHEN BPDUs RECIEVED
HOST PORT
DISCARDING
BACKUP
ALTERNATE
PER-VLAN SPANNING-TREE PLUS +
OPERATES OVER BOTH DOT1Q AND ISL
INTEROPERABILITY BETWEEN CST & PVST
PER-VLAN SPANNING-TREE
ISL BASED
1 INSTANCE OF STP PER VLAN
COMMON SPANNING-TREE
DOT1Q BASED (NATIVE VLAN)
1 INSTANCE OF STP
802.1D(TRADITIONAL)
TIMERS
MAX-AGE (20 sec)
FORWADING (15 sec)
HELLO (2 sec)
PORT STATES
FORWARDING
LEARNING
LISTENING
BLOCKED
DISABLED
PORT ROLES
BLOCKING
DESIGNATED
ROOT
SPEED CONVERGENCE
BACKBONE-FAST
FOR INDIRECT FAILOVER
UPLINK-FAST
FOR DIRECT FAILOVER
PORT-FAST
ON ACCESS LAYER CONNECTED TO HOSTS TO REMOVE MAX-AGE TIMER DELAY
STP PROTECTION
LOSS OF BPDUs
UDLD(UNI-DIRECTIONAL LINK DETECTION)
DETECTS BY SENDING KEEPALIVES
1 WAY OR DIRECTIONAL LINK DETECTION
LOOP-GUARD
WITH: PORT BECOME INCONSISTENT
WITHOUT: PORT STARTS FORWARDING
DETECTS LOSS OF BPDUs
BPDU FILTERING
REQIURES PORT-FAST
DISABLES BPDUs ON PORT