JA3 is a popular method to fingerprint TLS connections used by many monitoring tools and IDSs. JA3 focuses on encryption options specified during TLS connection setup to fingerprint the encryption library used by the application. Image courtesy of Cisco So in essence the same JA3 fingerprint will match multiple applications, making JA3 unreliable (when used […]
Encrypted Traffic Analysis: A Primer
Monitoring encrypted traffic is must for providing visibility in modern traffic. Due to this we’ve put a lot of energy in extending nDPI so that it could be useful in this context. DPI (deep packet inspection) however is not enough for complete visibility, and thus we have started to add classification techniques and algorithm to […]
Rethinking Network Flow Visualisation
Traffic monitoring applications often aggregate traffic in flows, that in essence is a way to divide traffic according to a 5-tuple key (Protocol, IP/port source/destination). Flows are then aggregated for instance according to IP address or protocol, and often represented with timeseries as the one below. What is missing in all this is how the […]
How to use nDPI from CLI to analyse network traffic
Most people use nDPI indirectly being it part of ntopng and many other non-ntop developed tools. However not many people know that nDPI can also be used from the command line to analyse network traffic. This is useful to create scripts to automate detection of specific issues. ndpiReader is a testing tool used to demonstrate […]
Introducing nDPI v3: Encrypted/Malware Traffic Analysis with Ease
Those who though that DPI died with the advent of traffic encryption should play with nDPI v3 that we’re introducing today. As already discussed, the pervasive use of encrypted traffic requires a new mindset when analysing network traffic. We decided to enhance nDPI adding the best traffic analysis techniques available today, in particular Cisco Joy, […]
How Encryption Changed Network Traffic (Monitoring). Finally.
For years traffic monitoring tools assumed traffic was in clear text. This because when the Internet was created all the main protocols such as DNS, HTTP, SMTP, Telnet, POP were in clear. With this practice it was easy to report let’s say the breakdown of DNS response codes, or detect force brute attacks on HTTP […]
New Challenges in DPI Protocol Detection
In the early Internet days, each network protocol was designed for a specific purpose: SMTP for sending emails, HTTP for the web and so on. In order to make sure that implementations where compliant with the specification, there was an RFC per protocol describing it. If a connection was starting with a protocol, let’s say […]
TLS/SSL Analysis: When Encryption and Safety Are Not Alike
Most people think that SSL means safety. While this is not a false statement, you should not take it for granted. In fact while your web browser warns you when a certain encrypted communication has issues (for instance them SSL certificates don’t match), you should not assume that SSL = HTTPS, as: TLS/SSL encryption is […]
nDPI 2.8-stable is Out
This new release brings several fixes that make nDPI more stable. Such fixes involve especially DNS and HTTP traffic dissection. Here is the full list of changes: New Supported Protocols and Services Added Modbus over TCP dissector Improvements Wireshark Lua plugin compatibility with Wireshark 3 Improved MDNS dissection Improved HTTP response code handling Full dissection […]
Traffic Classification Using nDPI over DPDK
Last week we have attended the DPDK Summit North America 2018 and talked about how to use nDPI over DPDK, a kernel-bypass toolkit similar to PF_RING. For those who have not attended the presentation, they can read the presentation slides. As you will be read, nDPI is a cross platform deep packet inspection toolkit able […]