Subnetting vs VLan
Hi experts,
I wish to know if I should divide a network in to subnets or I can use vlan or both?
Say if I use 192.168.10 as my network and the last octet as my host if I want 4 hosts I can simply chop it up with new subnet mask of 255.255.255.192 which gives me 4 hosts network (each subnet shouldn't be talking to one another unless I do some routing and set rules). I can also group the switch ports into different vlans and assign different network to each vlan. Say if I divide a 48ports switch into 4 hosts, then I will have 12 switchports per vlan and 192.168.10.x to vlan1 192.168.20.x to vlan2 etc... and device in different vlan will be assigned with different IP.
Will there be a case user will use subnet in conjunction with vlan? say if I divide the 192.168.10.x into 4 hosts and assign each host to each of the vlan instead of using different network? OR people will use either vlan or the subnet but not both together? Thanks.
I wish to know if I should divide a network in to subnets or I can use vlan or both?
Say if I use 192.168.10 as my network and the last octet as my host if I want 4 hosts I can simply chop it up with new subnet mask of 255.255.255.192 which gives me 4 hosts network (each subnet shouldn't be talking to one another unless I do some routing and set rules). I can also group the switch ports into different vlans and assign different network to each vlan. Say if I divide a 48ports switch into 4 hosts, then I will have 12 switchports per vlan and 192.168.10.x to vlan1 192.168.20.x to vlan2 etc... and device in different vlan will be assigned with different IP.
Will there be a case user will use subnet in conjunction with vlan? say if I divide the 192.168.10.x into 4 hosts and assign each host to each of the vlan instead of using different network? OR people will use either vlan or the subnet but not both together? Thanks.
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Noci is correct.
Defining 4 subnets and keeping them in the same VLAN (broadcast domain) is pointless.
Subnets should be in different VLAN's (broadcast domains). Keeping them in the same VLAN negates some of the reasons for creating the subnets in the first place. But you don't have to.
Defining 4 subnets and keeping them in the same VLAN (broadcast domain) is pointless.
Subnets should be in different VLAN's (broadcast domains). Keeping them in the same VLAN negates some of the reasons for creating the subnets in the first place. But you don't have to.
Well done Don, you have your technically correct answer. I'm sure it'll be appreciated.
To that end, sure, as you note you can place two to hundreds of subnets inside the same VLAN. And the first person that came behind you and saw the configuration would brand your design appropriately, if in fact your cheerful customer had not already done so.
To that end, sure, as you note you can place two to hundreds of subnets inside the same VLAN. And the first person that came behind you and saw the configuration would brand your design appropriately, if in fact your cheerful customer had not already done so.
Well, one can talk about VLANs and traffic separation and that's fine only up to a point. If ports on switches are trunked then the traffic for all the associated VLANs is shared. This might happen if switches are cascaded and, yet, there's a desire to carry the VLANS through the cascade.
Splitting a switch up into separate ports on separate VLANs accomplishes what's been described here - so there remain details to be understood and dealt with.
Splitting a switch up into separate ports on separate VLANs accomplishes what's been described here - so there remain details to be understood and dealt with.
?? A subnet is by definition a broadcast domain.