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Webcast-Catalyst9k
New Member

Layer 3 versus Layer 2

Is Layer 3 worth the extra money. No one at Ciaco seems to be able to tell me why I need Layer 3. I dont use VLANs, any QoS, VoIP. I have 250 users, enough bandwidth and no users complaining. Can anyone tell me why I should get Layer 3 instead of Layer 2? Thanks.

4 REPLIES
New Member

Re: Layer 3 versus Layer 2

Layer3 is for routing between VLANs or routing with other segment that's not part of your LAN. If you don't see you will seperate your LAN into VLANs, there is no need that I can see you would need a layer3 blade on your switch. All though it's always good to have in case you change your mind.

New Member

Re: Layer 3 versus Layer 2

One obvious reason would be to elimate your broadcasts from going to every machine on the sytem. With only Layer 2 your system is one large broadcast domain....

Gold

Re: Layer 3 versus Layer 2

Right--the first time you have a broadcast storm, you're going to be wanting some layer three seperation. Of course, you can do this with vlans, and connect the servers to every vlan in the network, and then have one router connected to every vlan to get to the Internet (you've just injected layer three, of course, but we'll ignore that). You could probably get by for a long time on this, as long as your server can handle the network load/etc.

But if your network grows, you will soon find that you want a router someplace to take the load off the servers, and to route between the vlans for multiple servers.

:-)

Russ

New Member

Re: Layer 3 versus Layer 2

When the no. of users grows, to manage the broadcast strom, surely we will be in need of routers. Also when we have two sepate buildings where we need to access datas from different vlans, there also rotuer

will come into pictute to do the intervlan routing.

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