Tag: firewall

Unable to access Cisco ASA through AnyConnect VPN?

I stepped on this issue few weeks ago. I was implementing a new ASA Firewall solution, first time for me with software newer than version 8.4.2

It seems that all those stories about changes in the NAT logic after that version were true. This is what I found out about ASA packet processing.firewall

Configuration was really straightforward and everything worked fine except one thing. When connected remotely using Cisco AnyConnect I was able to access all devices inside the network (inside ASA firewall), but not the ASA itself. I wasn’t able to connect with SSH nor with ASDM.

| Continue Reading.. |

Transparent Firewalls

A firewall in terms of traditional network configurations serves as a default gateway for hosts connecting to one of its secured subnets. A transparent firewall acts like a “stealth firewall” and it is actually a Layer 2 firewall. In order to implement this, the connection of the security equipment is made to same network on both the internal and external ports. However, there is a separate VLAN for each interface.

Now let’s discuss the characteristics of transparent firewall mode:

  • Transparent firewall mode supports outside interface and an inside interface.
  • The best thing about transparent firewall mode is that it can run in both the single and multiple context modes.
  • Instead of routing table lookups the MAC lookups are performed.

    | Continue Reading.. |

How does Firewall defend our Network?

firewall

We all are familiar with the term ‘firewall’ but majority of us don’t know the source of its origination. It is actually a terminology used for describing a part of automobile that separated the automobile’s interior from the compartment of engine. In the world of network this term is used metaphorically to show the way internal networks are separated from the hazards of external world. With the help of firewalls the networks are divided into various physical networks and as a result of this the occurrence of potential damages can be controlled otherwise these damages can spread to different subnets.

This works in the same way as the original firewalls worked to stop the spreading of a fire.

| Continue Reading.. |

Firewall – Defending Networks

In network security today, a firewall may be a software or hardware that makes a barrier between our internal network and untrusted external network. You can look at the firewall as a set of related programs that enforce an access control policy between two or more networks.

firewallThe name “firewall” is very strange, it has been originally used to describe the segment that separated the engine compartment from the interior of an automobile. In the networking world firewall is the first line of defense and the technology that will allow us to segment the network in physically separate subnetworks.

| Continue Reading.. |