A reason for a VLAN is to reduce STP workload?
Roguetadhg
Member Posts: 2,489 ■■■■■■■■□□
in CCNA & CCENT
I need some help to understand what is trying to be said through this. To Keep the context, i've typed down the bullets.
1. To create more flexible designs that group users by department, or by groups that work together, instead of physical locations.
2. To segment devices into smaller LANs (broadcast domains) to reduce overhead caused to each host in the VLAN
3. To reduce the workload for the Spanning Tree Protocol (STP) by limiting a VLAN to a single access switch.
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4. To enforce better security by keeping hosts that work with sensitive data on a separate VLAN.
5. To separate traffic sent by an IP phone from traffic sent by PCs connected to the phones.
I question #3:
I understand the VLANs cut broadcasts, and thanks to VTP Pruning (other than manually doing this), a VLAN to be not transferred to another switch. The only part where I remember VLANs mentioned in the STP is when there's PVSTP/PVRSTP mentioned. Otherwise I don't recall a single word otherwise, and even looking through the chapter isn't revealing anything to me.
1. To create more flexible designs that group users by department, or by groups that work together, instead of physical locations.
2. To segment devices into smaller LANs (broadcast domains) to reduce overhead caused to each host in the VLAN
3. To reduce the workload for the Spanning Tree Protocol (STP) by limiting a VLAN to a single access switch.
:4. To enforce better security by keeping hosts that work with sensitive data on a separate VLAN.
5. To separate traffic sent by an IP phone from traffic sent by PCs connected to the phones.
I question #3:
I understand the VLANs cut broadcasts, and thanks to VTP Pruning (other than manually doing this), a VLAN to be not transferred to another switch. The only part where I remember VLANs mentioned in the STP is when there's PVSTP/PVRSTP mentioned. Otherwise I don't recall a single word otherwise, and even looking through the chapter isn't revealing anything to me.
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lon21
Member Posts: 201
Sorry could you explain what you are trying to find out?
Where did you see this question? -
Roguetadhg
Member Posts: 2,489 ■■■■■■■■□□
Wendell Odem - ICND 2nd Edition. The fundamentals of VLANs.
I was looking for an explanation of how #3 is true
These are reasons people use VLANs.In order to succeed, your desire for success should be greater than your fear of failure.
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lon21
Member Posts: 201
Roguetadhg wrote: »Wendell Odem - ICND 2nd Edition. The fundamentals of VLANs.
I was looking for an explanation of how #3 is true
These are reasons people use VLANs.
Do you have a page number.
I guess when you have Per PVST it does not have to converge on switch which do not contain the vlan i.e when using vtp pruning. -
instant000
Member Posts: 1,745
I think of #3 LIKE THIS:
the fewer VLANs you have, the fewer instances of spanning tree you have to run. if the switch has only one VLAN, less instances of spanning tree to worry about.Currently Working: CCIE R&S
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Forsaken_GA
Member Posts: 4,024
Right, when a vlan has a convergence issue, *every* switch that has that vlan on it needs to run the STP alogorithim. So by cutting up your network and restricting a vlan to as few switches as possible, you do indeed lighten the STP load.
This concept actually goes for a number of routing protocols as well, and is part of the pro's for OSPF and EIGRP stub areas.