Two Internet connections one cup... I mean one switch

[santaslittlehelper]

I'm wondering if this is possible....

I have two internet connections that I would like to seperate from each other.  One connection I would use as for public internet access only, the other connection will be used for our private LANs internet access.

I have two buildings physically seperated that are connected via a 25 pair fiber, only one pair is currently used for the private LAN connection.

Here's the problem.

Using the surplus gbics and fiber patch cords I have make a seperate connection between buildings utilizing the same switches in each building (3560's) that I use for the private LAN connection and make a seperate connection between buildings that the public internet access would use.  Currently the two buildings are trunked together.    The public internet access and private lan should NOT be able to communicate to on and another, keeping each others traffic seperate.  I am unsure how I would setup the routing.  I have the one switch doing layer 3 due to each building being on its on subnet.

Is this possible.

[Reza Sharifi]

3560 is capable of doing VRF Lite.  If you want to keep them completely separate, than you can put the public Internet in one VRF going out one connection to Internet and the private network use a different VRF going out to Internet using the second connection.  Have a look at this doc for more info and config example:

http://www.cisco.com/en/US/docs/optical/15000r4_6/ethernet/454/guide/vrf.pdf

HTH