What is DNS traffic?How do I monitor DNS traffic
DNS is an important infrastructure, used for domain name services, load balancing, mobile IP and other important applications.DNS traffic surge impact on the normal operation of the Internet, and proposed malicious DNS traffic attacks, cellular effect concept, what is DNS traffic?What are the ways to monitor it?Take a look.What is DNS traffic?DNS is actually a device that converts web addresses into actual IP addresses of websites. It has a database of web addresses and actual IP addresses.The faster the connection speed is, the server in which you are connected will be the server in which you are connected, without compromising the response time.What are the methods for monitoring DNS traffic?1. Actual cases of Wireshark and Bro show that passive traffic analysis is effective in identifying malware traffic.The DNS data between the client and the parser is captured and filtered as PCAP (Network packet) files.Create a script to search these network packets for some kind of suspicious behavior you are investigating.Or SQL queries directly on network packets using PacketQ (originally DNS2DB).(Remember: Customers are prohibited from using any parsers or non-standard ports other than their own local parser.)2. DNS Passive replication This approach involves using sensors on parsers to create a database that contains all DNS transactions (queries/responses) through a given parser or group of parsers.The inclusion of DNS passive data in the analysis plays an important role in identifying malware domain names, especially when malware uses domain names generated by algorithms.The PaloAlto firewall and security management system that uses Suricata as an IDS (intrusion detection system) engine are examples of security systems that combine passive DNS with IPS (intrusion prevention system) to defend against known malicious domain names.3. Firewall All firewalls allow custom rules to prevent IP address spoofing.Add a rule to reject DNS queries from IP addresses outside the specified range to prevent domain name resolvers from being used as open reflectors in DDOS attacks.Enable DNS traffic detection to detect suspicious byte patterns or abnormal DNS traffic to prevent DNS software vulnerability attacks.Whether you’re using Snort, Suricata, or OSSEC, you can write rules that require your system to report DNS requests from unauthorized customers.You can also make rules to count or report NXDomain responses, responses with small TTL value records, DNS queries over TCP, DNS queries on non-standard ports, suspiciously large DNS responses, and so on.Any field or value in the DNS query or response information is basically “detectable.”The only limits are your imagination and your familiarity with DNS.Firewall IDS (Intrusion Detection System) provides both permit and deny configuration rules for most common detection items.