@inproceedings {Tra2014b, title = {Exploiting Hybrid Measurements for Network Troubleshooting}, booktitle = {IEEE Networks}, year = {2014}, month = {09/2014}, publisher = {IEEE}, organization = {IEEE}, address = {Funchal, PT}, abstract = {Network measurements are a fundamental pillar to understand network performance and perform root cause analysis in case of problems. Traditionally, either active or passive measurements are considered. While active measurements allow to know exactly the workload injected by the application into the network, the passive measurements can offer a more detailed view of transport and network layer impacts. In this paper, we present a hybrid approach in which active throughput measurements are regularly run while a passive measurement tool monitors the generated packets. This allows us to correlate the application layer measurements obtained by the active tool with the more detailed view offered by the passive monitor. The proposed methodology has been implemented following the mPlane reference architecture, tools have been installed in the Fastweb network, and we collect measurements for more than three months. We report then a subset of results that show the benefits obtained when correlating active and passive measurements. Among results, we pinpoint cases of congestion, of ADSL misconfiguration, and of modem issues that impair throughput obtained by the users.}, keywords = {Hybrid measurements, measurement analysis, WP2}, author = {Stefano Traverso and Edion Tego and Eike Kowallik and Stefano Raffaglio and Andrea Fregosi and Marco Mellia and Francesco Matera} } @inproceedings {Ber2012, title = {DNS to the rescue: Discerning Content and Services in a Tangled Web}, booktitle = {Internet Measurement Conference 2012}, volume = {1}, year = {2012}, month = {11/2012}, pages = {413-426}, publisher = {ACM}, organization = {ACM}, edition = {ACM}, address = {Boston, MA}, abstract = {

A careful perusal of the Internet evolution reveals two major trends - explosion of cloud-based services and video stream- ing applications. In both of the above cases, the owner (e.g., CNN, YouTube, or Zynga) of the content and the organiza- tion serving it (e.g., Akamai, Limelight, or Amazon EC2) are decoupled, thus making it harder to understand the associ- ation between the content, owner, and the host where the content resides. This has created a tangled world wide web that is very hard to unwind, impairing ISPs{\textquoteright} and network administrators{\textquoteright} capabilities to control the traffic flowing in their networks.

In this paper, we present DN-Hunter, a system that lever- ages the information provided by DNS traffic to discern the tangle. Parsing through DNS queries, DN-Hunter tags traf- fic flows with the associated domain name. This association has several applications and reveals a large amount of use- ful information: (i) Provides a fine-grained traffic visibility even when the traffic is encrypted (i.e., TLS/SSL flows), thus enabling more effective policy controls, (ii) Identifies flows even before the flows begin, thus providing superior net- work management capabilities to administrators, (iii) Un- derstand and track (over time) different CDNs and cloud providers that host content for a particular resource, (iv) Discern all the services/content hosted by a given CDN or cloud provider in a particular geography and time interval, and (v) Provides insights into all applications/services run- ning on any given layer-4 port number.

We conduct extensive experimental analysis and show re- sults from real traffic traces (including FTTH and 4G ISPs) that support our hypothesis. Simply put, the information provided by DNS traffic is one of the key components re- quired for understanding the tangled web, and bringing the ability to effectively manage network traffic back to the op- erators.\ 

}, keywords = {DNS, mPlane, passive measurement, WP2}, isbn = {978-1-4503-1705-4}, doi = {10.1145/2398776.2398819}, url = {http://dl.acm.org/citation.cfm?id=2398776.2398819\&coll=DL\&dl=GUIDE\&CFID=225051145\&CFTOKEN=42401286}, author = {Ignacio Nicolas Bermudez and Marco Mellia and Maurizio M Munafo{\textquoteright} and Ram Keralapura and Antonio Nucci} }