Securing an ISP Network

1
Securing an ISP Network

• by
• Brandon Moore
• for
• ITT Tech IS316

2
An ISPs Objective

• Provide internet service that is fast, reliable,
  and open for all types of communication.
• vs.
• Protect the network.

3
Port Blocking

• Customers are very discouraged by an ISP that
  actively blocks a port they need.
• However, some ports should never be open. For
  example, ports used by many well known viruses.

Well Known Viruses and Their Respective Ports
4
Bogons and Bad People

• Bogons are IP addresses that are designated as in
  a private or unallocated range and should not be
  seen creating connections to the network.
• Bad people are those that are known or have
  created a negative reputation for themselves.
  These people should not be allowed to originate
  sessions to anything on the network.

• Bogon Address Ranges
• Private IPs
• 10.0.0.0/8
• 192.168.0.0/16
• 172.16.0.0/12
• 169.254.0.0/16
• Unallocated IPs by IANA
• 100.0.0.0/8 133.0.0.0/8

• Blocking Countries
• Nigeria
• Russia
• Ukraine
• China
• Continuous assessment of
• incoming connections is crucial.

5
Incoming Spam

• A firewall is the first layer of defense against
  spam.
• By setting thresholds on what is an acceptable
  amount of SMTP connections most spam can
  eliminated.

6
Outgoing Spam

• Outgoing spam is spam originated by a customer of
  the ISP.
• Most cases are in result of a spam-bot downloaded
  by the customer unknowingly.

7
Q A

• Questions to ask ISP's.
• 1. Do you actively block usage of ports known to
  be exploited? If so, what ports?
• 2. What do you offer that can help protect me
  from spam? What about protecting the IP address I
  obtained from you?
• 3. Do you have an enforced security policy?
• 4. Can you offer me a public IP address where I
  control the network such as a /30 or /29?