What is the best way to set up a MAN?

[Vidmine]

I steped into a position where there is a current network set up. It's a MAN and I have not had much experience with them. They are running 1G out to all locations via metro ethernet. There are 6 locations each with Cisco 3560's to "terminate" the metro E at the host there is a Cisco 4506. There are about 100 vlans and the number will grow.
The VLANs are spread all over the network, meaning in location 1 there is vlan 300 with a specific network and task and several interfaces set up with access to vlan 300.
In location 2 we have VLAN 300 also with the same network and several ports set up with access to vlan 300.
Personally I don't like this set up.
Is there a better way?

 

[cajuntank]

Since you have Cisco equipment, I'll run you down the Cisco "CDA" model they preach.

Even though it's 1GbE, there's probably traffic passing across the links that don't need to be due to the fact that it has to talk to the L3 switch to route to the other subnets/vlans. So for example at siteB you have your 3560 and VLAN300 assigned to a couple of ports and say VLAN200 assigned to a couple of ports. If a resource on one of the VLAN300 ports needs to talk to a resource on one of the VLAN200 ports, then it will have to traverse to and fro the Metro link even though the resources are on the same switch.

Following Cisco CDA design, regardless of LAN, MAN, or WAN; you would have your "A=Access" level switches at your sites connecting to the 3560's. The 3560's would be the L3 switch for that site and only pass traffic to the other sites should your requests need to go to another subnet elsewhere. Those 3560's fall in Cisco's "D=Distribution" model and do the L3 routing and any ACL(s). The 4506 would be the "C=Core" in Cisco's model offering the fastest L2 switching for those connections coming in from the 3560's.

You don't have to have separate switches for each level (CDA); in smaller environments, the Core and Distribution switch might be the same device or the Access and Distribution switch might be the same device, etc... It's just Cisco's recommended network model.

Hope that helps.