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New Member

VLAN or subnet my network?

hi pleae help me,

i have 1 3550 L3 switch, 2 2950 connected on it and 1 2650 (with 10 pc's connected)also connected on a 3550.My boss wanted me to improve the network performance on this 10 pc's connected on 2650.

i have 120 total users including 10 pc's connected on 2650.

Is there any problem to use VLAN on 2650 or just use subnet on 10 pc's?

what is the difference between VLAN and subnet?

OR do you have any suggestion that will help to improve my 10 pc's network performance?

thanks all.


Re: VLAN or subnet my network?

what is the network address (ip add ) of these 10 pc's now?How are they affecting the performance now?

A VLAN is a logical local area network (or LAN) that extends beyond a single traditional LAN to a group of LAN segments, given specific configurations.All the users under one vlan will be in one network(subnets).

subnet is alogical division of a local area network, which is created to improve performance and provide security.

ie,all the users under vvlan should be in one subnet.U can place all users under one sunets without configuring vlans.Just configure all pc adress in one network range thats all.The configuration of vlan dependes on ur requirement to extend this network to other switches in ur network and utilising other features like STP etc..

New Member

Re: VLAN or subnet my network?

hi arukumar thanks for your repsonse.

currently im using 1 network address for the whole network.

Most of our users connecting to this 10 pc's to access some applications installed.

im thinking to use subnet not VLAN because of 10 pc's only.

Is there any problem to use subnet or what is the advantage than the VLAn for 10 pc's.


New Member

Re: VLAN or subnet my network?

You mention that you want to improve the network performance of the 10 pc's, have you done any baseline testing? Do you know what or where the bottleneck is occurring?

Sounds like the 10 pc's are part of a group that will communicate mostly between themselves, a vlan would reduce traffic from other pc's from reaching those 10. You can trunk to your 3500 and allow only vlan traffic that is required for those 10 pc's across the trunk link, this should speed up their performance. Etherchannel is the best trunking method to improve performance by providing load balancing and fault tolerance between the two switches.

A subnet would isolate them from the rest of the network sending all traffic not on the subnet out of a default gateway or to the bit bucket. It would help to know what type of connection you have to the 3550, can you configure a port channel/etherchannel between the two switches? That may also help, but to better understand your problem more detailed information will be required

Have a look at the document below for some more information.


Re: VLAN or subnet my network?

Is ur complete network ,ie network over other switchs also in one network range.?If so,its very strange.

As i understand ur these 10 pc's are some server sort of thing which is accessed by other users in the network.and since ur might have other switches have users i think its better u can configure two vlans for the entire network.

U might require a routing between the vlans ,but that not an issue as u have got a L3 Switch.

Eg:Vlan 10 for ur 10 pc network with range and other users on vlan 20 over the network with

On 2650 switches configure vlan with

#vlan 10

#name vlan10

on each port connecting to pc u can give

#switchport access vlan 10

on other switches u can create vlan 20 similarly on other switches for the users.

U can trunk the connection between others all switches to L3 switch(3550).

#switchport mode trunk

On L3 switch create an SVI for intervlan communication..

int vlan 10

ip add

int vlan 20

ip add

Give the gateway as the above address for pc's in respective vlans.

hope this might help


New Member

Re: VLAN or subnet my network?

What troubleshooting havr you done ?

have you checked the duplex settings between the switch ports and the PC's.