Allowing ISP Heartbeat messages
Internet Service Providers (ISPs) periodically send heartbeat messages to their connected dial-up customers to make sure they are still there. If the ISP cannot determine that the customer is there, it might disconnect the customer so that the user's IP address can be given to someone else.
By default, Zone Labs security software blocks the protocols most commonly used for these heartbeat messages, which may cause you to be disconnected from the Internet. To prevent this from happening, you can identify the server sending the messages and add it to your Trusted Zone or you can configure the Internet Zone to allow ping messages.
Indentifying the source of the heartbeat messages
This is the preferred solution because it will work whether your ISP uses NetBIOS or ICMP (Internet Control Message Protocol) to check your connection, and it allows you to maintain high security for the Internet Zone.
To identify the server your ISP uses to check your connection:
- When your ISP disconnects you, click Alerts & Logs|Log Viewer.
- In the alerts list, find the alert that occurred at the time you were disconnected.
- In the Entry Detail area, note the Source DNS detected.
If you're not able to identify the server this way, contact your ISP to determine which servers need access permission.
- After you have identified the server, add it to the Trusted Zone.
Configuring Zone Labs security software to allow ping messages
If your ISP uses ICMP echo (or ping) messages for connectivity checks, configure Zone Labs security software to allow ping messages from the Internet Zone.
To configure Zone Labs security software to allow ping messages:
- Select Firewall|Main.
- In the Internet Zone area, click Custom.
- Select check box labeled Allow incoming ping (ICMP echo).
- Click OK.
- Set the security level for the Internet Zone to Medium.
See Choosing security levels .
