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New Member

VLAN

i have a layer 2 switch, if i create two vlan's, without inter vlan routing the systems in both vlan's can't communicate.The same effect i feel simply i separate the systems using two subnet mask my qustion is that what is the diffrence between both (diffrent subnetmask and VLAN

3 REPLIES
Purple

Re: VLAN

If you simply use a single VLAN and separate hosts within that VLAN using different subnets, they will not be able to communicate directly at an IP layer without going through a router. However, the problem you create with this setup is that broadcasts sent by a host in one subnet will also be received by hosts in all other subnets belonging to the same vlan. When you use VLAN separation, broadcasts are local to each VLAN.

Hope that helps - pls do rate the post if it does.

Paresh

Re: VLAN

hi,

yes if you creat vlans and that have host in different vlan then also they are not able to communicate with each other becasue VLAN is the logical group of the switch ports... it means if you have four host... and you have two host in one vlan1 and two host in other vlan2... then if one of host in vlan1 will send brodcast any thing that will only receive by the host which is in the same vlan it means broadcast traffic of the vlan 1 will not pass to the other vlan2... so this is how you divid the broadcast...and this limited brodacst you can keep in perticular vlan even if you have more switches in the network with the same vlan configuration...

but letsay if you have 4 host with the different subnet but all are in the same vlan then even though they are in different subnet they will affected by the broadcast...

hope this will clear your idea

rate this post if it helps

regards

Devang

Bronze

Re: VLAN

Hii,

when u want two vlans to communicate it implies u need ip routing between two different lan subnets which is why router needs to pitch in.which means it is two different subnets have 2 vlan id.

talking of subnetmask it can be within a vlan or outside.if its within then its under the broadcast arena.

pls do rate the post.

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