
515151
© 2002, Cisco Systems, Inc. All rights reserved.
l2-security-bh.ppt
Spanning Tree Basics
STP is very simple. Messages are sent using Bridge Protocol Data
Units (BPDUs). Basic messages include: configuration,
topology change notification/acknowledgment (TCN/TCA); most
have no ÒpayloadÓ
Avoiding loops ensures broadcast traffic does not become storms
X
X
A Switch Is
Elected as Root
Root selection is
based on the lowest
configured priority
of any switch 0-
65535
F
F
F
F
F
F
F
B
B
F
F
F
A ÔTree-LikeÕ
Loop-Free Topology
Is Established from
the perspective of
the root bridge
F
F
A
Root
Root
B
STP Purpose: To maintain loop-free topologies in a
redundant Layer 2 infrastructure
Comentarios a estos manuales