What is Cisco deep packet inspection?

What is Cisco deep packet inspection?

Deep Packet Inspection (DPI) is a technique that allows network security devices such as firewalls to look “deeper” into the IP packet to try to learn its true intent.

What is inspection in Cisco ASA?

Internet protocol inspection also enables the ASA administrator to control traffic based on a number of different parameters that exist within the Internet traffic, including the information contained within the data portion of the traffic.

How do I check a stateful inspection on ASA?

ASA. Stateful Inspection

  1. Check if packet matches existing connection – if yes – go to 4th step.
  2. Check if ACL is configured and apply it to packet.
  3. If no ACL configured – follow to security-level pass-through logic.
  4. Stateful Inspection.

What is the packet flow of ASA firewall?

If packet flow does not match an existing connection, then TCP state is verified. If it is a SYN packet or UDP packet, then the connection counter is incremented by one and the packet is sent for an ACL check. If it is not a SYN packet, the packet is dropped and the event is logged.

What is SIP inspection?

SIP (Session Initiation Protocol) ALG (Application Layer Gateway) is an application within many routers. It inspects any VoIP traffic to prevent problems caused by firewalls and if necessary modifies the VoIP packets.

How disable SIP ALG Cisco ASA 5505?

Configuring via ASDM (ASA Only)

  1. Connect into the device using ASDM.
  2. Select Configuration, Firewall, Service Policy Rules.
  3. Open the Global Policy rule.
  4. Select Rule Actions, Protocol Inspection.
  5. Uncheck SIP.
  6. Click OK.
  7. Click Apply.
  8. Click Save.

How does a stateful inspection firewall work?

Stateful inspection monitors communications packets over a period of time and examines both incoming and outgoing packets. The firewall tracks outgoing packets that request specific types of incoming packets and allows incoming packets to pass through only if they constitute a proper response.

How does Asa process packets?

The packet is subjected to an Inspection Check. Cisco ASA has a built−in inspection engine that inspects each connection as per its pre−defined set of application−level functionalities. If it passed the inspection, it is moved forward. Otherwise, the packet is dropped and the information is logged.

How does firewall process packets?

The packet enters the host from the inbound NIC. As the inbound packet moves toward the IP module, the firewall intercepts it and applies inbound rules. If the inbound policy accepts the packet, the firewall sends the inbound packet to the IP module.

Is deep packet inspection necessary?

If your organization has users who are using their laptops for work, then deep packet inspection is vital in preventing worms, spyware, and viruses from getting into your corporate network.