How to split existing network into two using separate firewalls?

Posted on 2012-09-18
Last Modified: 2012-10-01
Hello Experts,

Here is a tricky question; well maybe to some of you it will be easy to answer... I work for a company which is managed by another outsourced company.  We have an existing network which sort of ties into their remote network via private networks.  To make a long story short, they will not grant me access to our firewall because it is tied into their network so they are saying it will be a security breach to them, so therefore, they will not give me access to the firewall.  What I want to know, without going into too much detail unless it is needed, is is there anyway to break our existing network into two and get our own firewall for just our network so that we can manage our own network and not have any ties with them?  Without concern for company policies because I was already given the go ahead to investigate this by my superiors, can this be done?  Thanks in advance.
Question by:Brent Johnson
    1 Comment
    LVL 7

    Accepted Solution

    Firewalls can be quite complex in their configuration.  In an extreme situation, you could position a layer 2 'transparent' firewall on your side of the existing firewall.  Generally this allows you to 'break your network in 2', and its generally 'invisible' to layer 3 infrastructure.  However, this is quite a complex setup, and I would not generally recommend it.

    I very much recommend talking to the MSP about lack of firewall control being an issue, and that if they cannot provide access at a reasonable cost, then it will be your intention to position your own firewall 'inline' with theirs.  If you add a normal layer 3 firewall inline, you will generally need them to reconfigure the routing on the firewall.

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