Information Security Blocklist

Campus Block Lists

The campus block lists provide the campus IT support community with a list of Internet resources and organizations which are denied access to the campus communications infrastructure.

Virus Block Lists

The campus mail infrastructure scans incoming mail and strips attachments containing viruses. Virus identification services are provided by Sophos Plc.

Spam Block Lists

Rogue organizations may be denied the privledge of sending mail to members of the campus community. Spam corporations may send mail directly or through third parties which may be unaware of the problem.

Servers and networks known to cause spam may be blocked by static lists of IP–blocks or by the use of dynamic spam block-lists. Many of these dynamic lists are maintained by consortiums outside the control of the campus, but provide valuable information about potential sources of spam.

CSUN's Dynamic spam blocking lists:

• SBL - Spamhaus Block List
• CBL - Composite Blocking List
• NJABL - Not Just Another Bogus List

Network Traffic Block Lists

Rogue organizations may be denied all ability to contact the campus network via the internet if they have proven to be a serious threat. Examples include probing for passwords and some forms of denial-of-service attacks.

The network is protected by the DShield - Distributed Intrusion Detection System external dynamic list.

The campus network prevents access from the following locations:

• Known-invalid external IP blocks, e.g. 127.0.0.0/8
• Unused CSUN subnets
• Abusive or compromised CSUN hosts

Internal hosts may be blocked based upon the Media Access Control (MAC) address of the network interface, e.g. 00:00:00:00:00:00