Spanning Tree Protocol Study Guide - Revision history

Haug0445 at 21:27, 30 January 2012

2012-01-30T21:27:54Z

← Older revision		Revision as of 21:27, 30 January 2012
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	RSTP ~~Ports~~ States:		===RSTP===

			RSTP Porty States:
	*Discarding		*Discarding
	*Learing		*Learing
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	The discarding state of RSTP is equivalent to the Blocking and Listening states of STP		The discarding state of RSTP is equivalent to the Blocking and Listening states of STP

	RSTP Port Roles		RSTP Port Roles:
	*Root: The port going toward the root bridge		*Root: The port going toward the root bridge
	*Designated: There is one on each segment. It receives the frames from the root port.		*Designated: There is one on each segment. It receives the frames from the root port.

Haug0445 at 21:26, 30 January 2012

2012-01-30T21:26:15Z

← Older revision		Revision as of 21:26, 30 January 2012
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	Greg Haug/Monique Moison/Clay Wilson/Matt Morisz		====Written by: Greg Haug/Monique Moison/Clay Wilson/Matt Morisz====

			==Spanning Tree Sudy Guide==

	Evolution of STP Basics		Evolution of STP Basics
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	There are many varieties of STP...[pg 120]		There are many varieties of STP...[pg 120]

	*DEC STP		:*DEC STP
	*802.1D		:*802.1D
	*Common Spanning Tree (CST)		:*Common Spanning Tree (CST)
	*Per VLAN Spanning Tree Plus+		:*Per VLAN Spanning Tree Plus+
	*Rapid STP (RSTP)/IEEE 802.1w		:*Rapid STP (RSTP)/IEEE 802.1w
	*Multiple Spanning Tree(MST)		:*Multiple Spanning Tree(MST)
	*PVRST+		:*PVRST+

	STP How it operates...		====STP How it operates...====
	The Steps:		The Steps:
	:*STP initially converges on a logically loop-free network topology.		:*STP initially converges on a logically loop-free network topology.
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	*In the event of a tie, the bridge ID acts as the tiebreaker		*In the event of a tie, the bridge ID acts as the tiebreaker

	Port Roles		===Port Roles===

	The are four roles of ports under STP		The are four roles of ports under STP
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	:*FOrwarding		:*FOrwarding
	:*Disabled		:*Disabled
	~~--------~~


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	An edge port is directly connected to an end point and are allowed to transistion directly into forwarding. This is like portfast except that in an edge port receives a BPDU it will automatically become a normal spanning-tree port.		An edge port is directly connected to an end point and are allowed to transistion directly into forwarding. This is like portfast except that in an edge port receives a BPDU it will automatically become a normal spanning-tree port.

			===RSTp Topology Change Mechanism===
	~~----~~

	RSTp Topology Change Mechanism

	When an RSTP bridge detects a topology change it performs the following actions.		When an RSTP bridge detects a topology change it performs the following actions.
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	If the TC While timer is running on a port, the BPDU’s sent out of that port have the TC bit set. While the timer is active the bridge sends BPDU even on the root port.		If the TC While timer is running on a port, the BPDU’s sent out of that port have the TC bit set. While the timer is active the bridge sends BPDU even on the root port.

	Bridge Identifier for PVRST+		===Bridge Identifier for PVRST+===

	Bridge Priority: A 4-bit field still used to carry bridge priority. In values of 4096. Default value is 32,768.		Bridge Priority: A 4-bit field still used to carry bridge priority. In values of 4096. Default value is 32,768.
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	(MST) Multiple Spanning Tree		(MST) Multiple Spanning Tree

	PortFast		===PortFast===

	Spanning Tree Portfast causes an interface configured as a layer 2 access port to enter the forwarding state immediately.		Spanning Tree Portfast causes an interface configured as a layer 2 access port to enter the forwarding state immediately.
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	spanning tree- vlan 3 root secondary		spanning tree- vlan 3 root secondary

	Multiple Spanning Tree		===Multiple Spanning Tree===

	MST extends the IEEE 802.1w RST algorithm to multiple spanning trees. The main purpose of MST is to reduce the total number of spanning-tree instances.		MST extends the IEEE 802.1w RST algorithm to multiple spanning trees. The main purpose of MST is to reduce the total number of spanning-tree instances.

Haug0445 at 21:22, 30 January 2012

2012-01-30T21:22:52Z

← Older revision		Revision as of 21:22, 30 January 2012
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			Greg Haug/Monique Moison/Clay Wilson/Matt Morisz

	Evolution of STP Basics		Evolution of STP Basics
	Evolution of STP		Evolution of STP
Line 15:		Line 17:
	STP How it operates...		STP How it operates...
	The Steps:		The Steps:
	*STP initially converges on a logically loop-free network topology.		:*STP initially converges on a logically loop-free network topology.
	*Elects one root bridge		:*Elects one root bridge
	*Selects the root port on all non-root bridges		:*Selects the root port on all non-root bridges
	*Selects the designated port on each segment		:*Selects the designated port on each segment

	Breaking the STP Steps down:		Breaking the STP Steps down:

	Step One		Step One
	*Elects One Root Bridge		:*Elects One Root Bridge
	*The protocol uses a process to elect a root bridge		:*The protocol uses a process to elect a root bridge
	*Only one bridge acts as the root bridge in a given network per VLAN		:*Only one bridge acts as the root bridge in a given network per VLAN
	*On the root bridge, all ports act as designated ports		:*On the root bridge, all ports act as designated ports
	*Switch with lowest priority parameter is elected as root		:*Switch with lowest priority parameter is elected as root

	Step Two		Step Two
	*Selects the Root Port on All Non-root Bridges		:*Selects the Root Port on All Non-root Bridges
	*The protocol establishes one root port on each non-root bridge.		:*The protocol establishes one root port on each non-root bridge.
	*The root port is the lowest-cost path from the non-root bridge to the root bridge		:*The root port is the lowest-cost path from the non-root bridge to the root bridge

	Step Three		Step Three
Line 43:		Line 45:

	The are four roles of ports under STP		The are four roles of ports under STP
	1)Root		:1)Root
	2)Designated Port		:2)Designated Port
	3)Non-designated Port		:3)Non-designated Port
	4)Disabled		:4)Disabled

	STP Port states:		STP Port states:
	*Blocking		:*Blocking
	*Listening		:*Listening
	*Learning		:*Learning
	*FOrwarding		:*FOrwarding
	*Disabled		:*Disabled
	--------		--------

Haug0445 at 21:19, 30 January 2012

2012-01-30T21:19:36Z

← Older revision		Revision as of 21:19, 30 January 2012
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	There are many varieties of STP...[pg 120]		There are many varieties of STP...[pg 120]

	*DEC STP		*DEC STP
	*802.1D		*802.1D
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	*PVRST+		*PVRST+

	STP		STP How it operates...
			The Steps:
	*STP initially converges on a logically loop-free network topology.		*STP initially converges on a logically loop-free network topology.
	*Elects one root bridge		*Elects one root bridge
	*Selects the root port on all ~~nonroot~~ bridges		*Selects the root port on all non-root bridges
	*Selects the designated port on each segment		*Selects the designated port on each segment

	STP Steps ~~(cont)~~		Breaking the STP Steps down:

			Step One
	*Elects One Root Bridge		*Elects One Root Bridge
	*The protocol uses a process to elect a root bridge		*The protocol uses a process to elect a root bridge
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	*Switch with lowest priority parameter is elected as root		*Switch with lowest priority parameter is elected as root

	~~STP~~ Step ~~2 (cont)~~		Step Two

	*Selects the Root Port on All Non-root Bridges		*Selects the Root Port on All Non-root Bridges
	*The protocol establishes one root port on each ~~nonroot~~ bridge.		*The protocol establishes one root port on each non-root bridge.
	*The root port is the lowest-cost path from the ~~nonroot~~ bridge to the root bridge		*The root port is the lowest-cost path from the non-root bridge to the root bridge

	~~Step 3~~

			Step Three
	*Selects Designated Port on Each Segment		*Selects Designated Port on Each Segment
	*On each segment, STP establishes one designated port on the bridge that has the lowest path cost to the root bridge		*On each segment, STP establishes one designated port on the bridge that has the lowest path cost to the root bridge

Haug0445 at 21:13, 30 January 2012

2012-01-30T21:13:53Z

@@ Line 1: / Line 1: @@
 Evolution of STP Basics
 Evolution of STP
-STP (Spanning Tree Protocol) – Eliminates loops at layer 2 topology
+What is STP? (Spanning Tree Protocol) – Eliminates loops at layer 2 topology
 STP
 STP initially converges on a logically loop-free network topology.
-Elects one root bridge
+*STP initially converges on a logically loop-free network topology.
-Selects the root port on all nonroot bridges
+*Elects one root bridge
-Selects the designated port on each segment
+*Selects the root port on all nonroot bridges
 STP Steps (cont)
 Elects One Root Bridge
-The protocol uses a process to elect a root bridge
+*Elects One Root Bridge
-Only one bridge acts as the root bridge in a given network per VLAN
+*The protocol uses a process to elect a root bridge
-On the root bridge, all ports act as designated ports
+*Only one bridge acts as the root bridge in a given network per VLAN
-Switch with lowest priority parameter is elected as root
+*On the root bridge, all ports act as designated ports
 STP Step 2 (cont)
 Selects the Root Port on All Non-root Bridges
-The protocol establishes one root port on each nonroot bridge.
+*Selects the Root Port on All Non-root Bridges
-The root port is the lowest-cost path from the nonroot bridge to the root bridge
+*The protocol establishes one root port on each nonroot bridge.
 Step 3
 Selects Designated Port on Each Segment
-On each segment, STP establishes one designated port on the bridge that has the lowest path cost to the root bridge
+*Selects Designated Port on Each Segment
-The switch primarily chooses a designated port as the least-cost path to the root bridge
+*On each segment, STP establishes one designated port on the bridge that has the lowest path cost to the root bridge
-In the event of a tie, the bridge ID acts as the tiebreaker
+*The switch primarily chooses a designated port as the least-cost path to the root bridge
 Port Roles
 The are four roles of ports under STP
 )Root
@@ Line 61: / Line 78: @@
 An edge port is directly connected to an end point and are allowed to transistion directly into forwarding. This is like portfast except that in an edge port receives a BPDU it will automatically become a normal spanning-tree port.

Haug0445 at 21:02, 30 January 2012

2012-01-30T21:02:55Z

← Older revision		Revision as of 21:02, 30 January 2012
Line 50:		Line 50:
	*Root: The port going toward the root bridge		*Root: The port going toward the root bridge
	*Designated: There is one on each segment. It receives the frames from the root port.		*Designated: There is one on each segment. It receives the frames from the root port.
	*Alternate: A port that is blocked but is an alternate path to the root bridge.		*Alternate: A port that is blocked but is an alternate path to the root bridge. Would go into forwarding stat if root port goes down.
	*Backup: A port that is blocked because it is a redundant link to the root bridge.		*Backup: A port that is blocked because it is a redundant link to the root bridge and has the higher port ID. Would go into forwarding stat if root port goes down.
	*Disabled		*Disabled: Plays no role in spanning-tree

			RSTP relies on the variables of Link type and Edge ports to achieve fast convergence.

			The link types are:
			*Point-to-point: full-duplex port
			*Shared: half duplex port

			An edge port is directly connected to an end point and are allowed to transistion directly into forwarding. This is like portfast except that in an edge port receives a BPDU it will automatically become a normal spanning-tree port.

Haug0445: Created page with "Evolution of STP Basics Evolution of STP STP (Spanning Tree Protocol) – Eliminates loops at layer 2 topology STP STP initially converges on a logically loop-free network topo..."

2012-01-30T20:58:13Z

Created page with "Evolution of STP Basics Evolution of STP STP (Spanning Tree Protocol) – Eliminates loops at layer 2 topology STP STP initially converges on a logically loop-free network topo..."

New page

Evolution of STP Basics
Evolution of STP
STP (Spanning Tree Protocol) – Eliminates loops at layer 2 topology

STP
STP initially converges on a logically loop-free network topology.
Elects one root bridge
Selects the root port on all nonroot bridges
Selects the designated port on each segment
STP Steps (cont)
Elects One Root Bridge
The protocol uses a process to elect a root bridge
Only one bridge acts as the root bridge in a given network per VLAN
On the root bridge, all ports act as designated ports
Switch with lowest priority parameter is elected as root
STP Step 2 (cont)
Selects the Root Port on All Non-root Bridges
The protocol establishes one root port on each nonroot bridge.
The root port is the lowest-cost path from the nonroot bridge to the root bridge

Step 3
Selects Designated Port on Each Segment
On each segment, STP establishes one designated port on the bridge that has the lowest path cost to the root bridge
The switch primarily chooses a designated port as the least-cost path to the root bridge
In the event of a tie, the bridge ID acts as the tiebreaker
Port Roles
The are four roles of ports under STP
1)Root
2)Designated Port
3)Non-designated Port
4)Disabled

STP Port states:
*Blocking
*Listening
*Learning
*FOrwarding
*Disabled
--------

RSTP Ports States:
*Discarding
*Learing
*Forwarding

The discarding state of RSTP is equivalent to the Blocking and Listening states of STP

RSTP Port Roles
*Root: The port going toward the root bridge
*Designated: There is one on each segment. It receives the frames from the root port.
*Alternate: A port that is blocked but is an alternate path to the root bridge.
*Backup: A port that is blocked because it is a redundant link to the root bridge.
*Disabled