What is Transparent Firewall ?

Transparent firewall works on layer 2.It connect two Router in a same layer .Firewall work like bridge. All interface in firewall assign interface zone according to Rule of firewall but do not assign ip address in interface .IP address assign on Device .

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Some of the features of transparent firewall

  1. Each interface is a broadcast domain.
  2. ASA performing secure transparent bridging between two broadcast domains in form of VLA
  3. No routing protocol to troubleshoot
  4. In common mode is going to see route lookup. In transparent mode it going to see media access lookup.
  5. It supports – mac application talk, IPX traffic, MPLS traffic, BPDU traffic,
    • ARP inspection (most popular transparent inspection)

Unsupported features of transparent firewall

  1. Dynamic DNS
  2. HDCP relay
  3. Dynamic routing protocol
  4. Multicast ip routing
  5. QOS (no investigation on layer 3)
  6. VPN termination
  7. Before 8.2 it doesn’t support

Transparent Firewall guideline

  1. Management ip address required on same subnet
  2. Inside/outside only pass traffic
  3. Each connection network on same subnet
  4. Default gateway will be router on the other side of ASA