LAN routing

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Apr 5th, 2007
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i have 2950G 24+2GB in 3rd Floor,3500 in 4th floor and 4006 in 5 th Floor.all these are conected to the core 3550G in 5th Floor.

i want the routing to happen with in the floor insted of going to the core in the 5 th Floor.

ie when the user communicaes btw floor, they should not go to core in 5th .insted routing should happen per floor

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Danilo Dy Thu, 04/05/2007 - 23:24
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Your objective is that when user in the same floor communicates with each other, they should not go to the core in 5th floor?

This can be achieve by assigning vlan per floor. Enable vtp pruning as well

Network administrator best practices is create a vlan per department and service to implement some level of security. If there are multiple department in one floor and you plan to combine them in one vlan, this need to be discuss with each department technical representative (if any).

However, if you really want to run routing per floor (and retain vlan per department and service). Identify distribution switches in each floor that can be connected with bigger port (GE) to the core switches in 5th floor and can be installed with EMI (L3) IOS image

abychan22 Thu, 04/05/2007 - 23:29
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Thanks for the replay.

not only within the floor.but also when the users from different floor tries to talk themselves. i mean inter floor communication.

is there any way like priority something like that?

Danilo Dy Thu, 04/05/2007 - 23:41
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Well, if all switches connections end (terminated) in the 5th floor core switch, whatever you do they will reach 5th floor. You will need to plan for a revamp of their physical connection.

But in my experience, I recommend following;

- access switches in each floor terminates (FE) at the distribution switches (recommended two for redundancy) in the same floor.

- distribution switch in each floor terminates (GE) at the core switch (recommended two for redundancy)

- vlan for each department, service (network printer), wireless, meeting room.

Why would you like to prevent the routing between users to reach core switch anyway?

abychan22 Thu, 04/05/2007 - 23:38
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is there any comands in which i can do interfloor routing without disturbing the core?

Danilo Dy Thu, 04/05/2007 - 23:44
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If all distribution switches running EMI, I recommned you run dynamic routing protocol (i.e. OSPF) among distribution switches and core switches. So as not to route traffic between users in different floors reach core switch, make physical connections between distribution switches (need not to be fully meshed). This way, only traffic destined to other networks (internet, remote sites, servers, even networked printers) will reach core switches.

Danilo Dy Fri, 04/06/2007 - 00:26
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I'm an OSPF guy :)

As mentioned earlier, your objective is technically possible.

- access switch in each floor connects to distribution switch in the same floor.

- distribution switch in each floor connect to core switch in 5th floor

- distribution switch in each floor connect to each other (need not to be physcially fully meshed)

- vlan per department, service (networked printer/copier), meeting room, wireless

- run dynamic routing protocol in distribution switches and core switches that routing between users in each floor will remain in distribution switches, only routing to other services (i.e. internet, networked printer/copier, remote sites, servers) will reach core switch.

Good luck!

abychan22 Fri, 04/06/2007 - 02:24
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Please confirm whether RIP-V2 will work in this kind of environment!! becoz am not in a position to use OSPF.


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