3com 4250T Switches Creating VLAN s with 802.1Q tagged connections - can I get traffic out on my Cisco 1702

Posted on 2005-05-12
Last Modified: 2010-05-18
This is similar to previous question that lrmoore answered so well..but I don't get to use Cisco switches..or even layer 3 switches.. trying to make this happen with Layer 2 3com switches...

So..a landlord is providing broadband to his tenants.

Time Warner Telecom supplies a managed router that is dishing out a 10MB of pipe
My Cisco 1700 series router has (2) ethernet interfaces
My 3Com 4250T 48 port, layer 2 switches with support for 802.1q tagging

The goal:

Give broadband to tenants, but dont allow them to "see" one another on the network..just let them get out to the internet.

Tenant1 will be on VLAN1 on the 3com 4250T switch with an assigned IP of
Cisco 1700's FastEthernet 1 is also part of VLAN1

So Tenant1 wants to go to the web.. wouldn't that request get passed to the Cisco, which would route out to the Time Warner router and then out the door...assuming that the Tenant and the Cisco were part of the same VLAN?



Question by:pdxsrw
    LVL 5

    Accepted Solution

    Yeah, it should work that way, but more information would help.  Provide more detail on how you see your routers and VLANs interconnected.  Also note whether you can add interfaces to either router.

    LVL 5

    Author Comment

    add physical  interfaces? I can add as many sub-interfaces that i need to on the Cisco 1700 series.. I can't rouch the Time Warner router though as it is a 'managed service'.

    I am planning on have the Cisco plugged into a port on the 3com switch that will be tagged with the 802.1q tagging and thus part of a port in the various VLANs I will create...

    LVL 5

    Author Comment

    This installation worked...was able to use ACL's on the Cisco router to restrict each IP address to only route out. Because of the frame tagging capability of the 802.1q 3com switches I was able to allow each VLAN to see the Cisco and get out to the web.

    However, to make this even easier, I would suggest using Layer3 switches...   I was using layer 2 switches... not by choice.

    Please close this question.


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