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Could you help me with my firewall requirement analysis?

I am working in an IT solution company, and we give customers solutions as per their requirements.

When discussing firewalls -- what do you think are questions that I should ask my customer? If am selling him a Cisco PIX firewall -- how can I get those answers to help me to prepare my BoM. In short how could I size the firewall for the customer?
Requirement analysis plays an important role in determining and recommending any technical solution. Apart from the pricing and budgetary factors, the analysis needs to gather the technical information. The major technical information you need are:

  • The size of network (Servers, workstations, switches etc.) at the client site.

  • Network Topology and design.

  • WAN connectivity- Number of sites connected/ Internet/ Connectivity channel and Pipe size.

  • Level of security - Basic packet filtering/NAT/PAT/State inspection.

  • If any security solution already in place?

  • Appliance or Software based solutions - Both of these have their own benefits.

  • Network Traffic Analysis- This is another factor which determines the type and size of firewall.

  • Firewall throughput- Many a times, throughput is also a deciding factor along with security features.

  • IDS/VPN's and other integrated technologies- Most of the companies now lookout for the solution which can provide them all of these as one solution. For example, a client might want to be able to terminate 100 plus VPN connections with a PIX firewall. This might seem okay as a solution, but could be hard on pricing or performance. Here you can suggest some VPN concentrators which take off load from the PIX.

  • Level of Support and training.

  • Product loyalty- This plays an important role. Many companies like to stick with the vendors they have been working with.
  • Answers to the above mentioned questions should give a fair analysis of the requirements.

    Let me know if you need further information.

    This was last published in December 2003

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