All Blog Posts

ntopng

Network Security Analysis Using ntopng

Most security-oriented traffic analysts rely on IDSs such as Bro or Suricata for network security. While we believe that they are good solutions, we have a different opinion on this subject. In fact we believe that it is possible to use network traffic monitoring tools like ntopng to spot many security issues that would make and IDS too complex/heavy to use (if possible at all). What many of our users are asking, is the ability to highlight possible scenarios where there is a potential security issue to be analysed more in …
PF_RING

Capture, Filter, Extract Traffic using Wireshark and PF_RING

Last year we introduced our new nBPF library able to: 1. Convert a BPF filter to hardware rules for offloading traffic filtering to the network card, making it possible to analyse traffic at 100G. 2. Accelerate traffic extraction from an indexed dump set produced by n2disk, our traffic recording application able to produce multiple PCAP files together with an index. Along with that library we released a tool n2if, able to create virtual interfaces to be used in Wireshark for implementing line-rate hardware packet filtering at 100G with Wireshark and filtering terabytes …
Guides

Filling the Pipe: Exporting ntopng Flows to Logstash

Logstash comes in very handy when it is necessary to manipulate or augment data before the actual consolidation. Typical examples of augmentation include IP address to customer ID mappings and geolocation, just to name a few. ntopng natively supports network flows export to Logstash. The following video tutorial demonstrates this feature. …
News

Meet ntop on April 28th @ Microsoft Munich

This year we’ve accepted the invitation from Wuerth-Phoenix to be part of their Roadshows 2017 and talk about network and system monitoring. The first workshop will be in Munich, Germany on April 28th. All ntop users are invited to come and talk about our monitoring tools.   ntop am 28. April bei Microsoft in München Wie wird die IT zu einem echten Service Enabler? Wie wird sich das Monitoring im Zeitalter von Industrie 4.0 entwickeln? Welche Neuigkeiten sind herstellerübergreifend in nächster Zeit zu erwarten? Eine neue Form des Managements und Monitorings …
ntop

What Is a Microburst and How to Detect It?

It’s not uncommon to see network administrator struggling tracking down packet drop on network equipments at interface level, while having a low average link utilisation. At the end it often turns out to be due to a phenomenon (well) known as microburst. While forwarding data between network links, network equipments absorb spikes with buffers, when buffers fill much quicker than they empty because of a line-rate burst, they overflow and packet loss occurs (yes you drop even though your like is in average little used). Now it’s clear that having …
nProbe

Collecting Proprietary Flows with nProbe

nProbe has been originally designed as an efficient tool able to capture traffic packets and transform them into flows. Call it network probe or sensor. Over the years we have added the ability to collect flows (i.e. nProbe is both a probe and a collector), so that nProbe can now act as probe, collector, also proxy by covering flows across formats. For instance you can collect IPFIX flows and export them in NetFlowV9. All this following the standards as confirmed by the IPFIX interoperability tests. Until now we focused in …
PF_RING

Positioning PF_RING ZC vs DPDK

Last week I have met some PF_RING ZC and DPDK users. The idea was to ask questions on PF_RING (for the existing ZC users) and understand (for DPDK users) whether it was a good idea to jump on ZC for future projects or stay on DPDK. The usual question people ask is: can you position ZC vs DPDK? The answer is not a simple yes/no. Let’s start from the beginning. When PF_RING was created, we have envisioned an API, persistent across network adapters, able to give people the ability to …
ntopng

Clustering Network Devices using ntopng Host Pools

In computer networks, devices are identified by an IP and a MAC. The IP can be dynamically assigned (so it might not be persistent), whereas the MAC is (in theory) unique and persistent for identifying a device. Non-technical users, do not know these low-level details, and in general it makes sense to cluster devices using other criteria. VLANs are a way to logically group devices belonging to the same administrative domain, but this is still a low-level network-level properly. When administering a network, we have have realised that we need …
nProbe

Flow-Based Monitoring, Troubleshooting and Security using nProbe

nProbe is a tool developed over the last 10 years, and thus it has been extended and improved year by year. However many users, even those who are using it since a long time, might not know all its features. Next week at Flocon 2017, I will give a talk about nProbe. The idea is to position nProbe (e.g. against the popular YAF tool), highlight what people can do with it (in addition to traffic monitoring and troubleshooting) and learn that nProbe is much more than a network sensor. I invite …
nProbe

Monitoring VoIP Traffic with nProbe and ntopng

VoIP applications usually limit theirs monitoring capabilities to the generation of CDR (Call Data Records) that are used for the generation of billing/consumption data. In essence you know how many calls a certain user/number has made, the duration etc. While this information can be enough for basic monitoring, it is not enough for guaranteeing reliable call quality as these systems are essentially blind with respect to call quality. Wireshark can analyse both call signalling and voice, but it is a troubleshooting tool meaning that it cannot be used for permanent …
cento

Stream That Flow: How to Publish nProbe/Cento Flows in a Kafka Cluster

Apache Kafka can be used across an organization to collect data from multiple sources and make them available in standard format to multiple consumers, including Hadoop, Apache HBase, and Apache Solr. nProbe — and it’s ultra-high-speed sibling nProbe cento — integration with the Kafka messaging system makes them good candidates source of network data. The delivery of network data to a redundant, scalable, and fault-tolerant messaging system such as Kafka enables companies to protect their data even in-flight, that is, when the consolidation in a database has still to occur. An impatient reader who is eager to use Cento for …
ntopng

ntopng MySQL Flow Export: Increase the Maximum Number of Open Files

ntopng uses partitioned MySQL tables when storing flows. As MySQL needs a file handle for each partition and its index, it is important to make sure that the open_files_limit is large enough to allow the process to keep all these files open. Typically, open_files_limit  default value works out-of-the-box but there are some packages/distributions that keeps this number pretty low. When the current value is too low, ntopng can show errors such as [MySQLDB.cpp:55] ERROR: MySQL error: Out of resources when opening file './ntopng/flowsv6#P#p23.MYD' (Errcode: 24 - Too many open files) [rc=-1] …