@inproceedings {Hou2015, title = {A Study of the Impact of DNS Resolvers on Performance Using a Causal Approach}, booktitle = {Internet Teletraffic Congress}, year = {2015}, month = {08/2015}, address = {Ghent, Belgium}, abstract = {For a user to access any resource on the Internet, it is necessary to first locate a server hosting the requested resource. The Domain Name System service (DNS) represents the first step in this process, translating a human readable name, the resource host name, into an IP address. With the expansion of Content Distribution Networks (CDNs), the DNS service has seen its importance increase. In a CDN, objects are replicated on different servers to decrease the distance from the client to a server hosting the object that needs to be accessed. The DNS service should improve user experience by directing its demand to the optimal CDN server. While most of the Internet Service Providers (ISPs) offer a DNS service to their customers, it is now common to see clients using a public DNS service instead. This choice may have an impact on Web browsing performance. In this paper we study the impact of choosing one DNS server instead of another and we compare the performance of a large European ISP DNS service with the one of a public DNS service, Google DNS. We propose a causal approach to expose the structural dependencies of the different parameters impacted by the DNS service used and we show how to model these dependencies with a Bayesian network. This model allows us to explain and quantify the benefits obtained by clients using their ISP DNS service and to propose a solution to further improve their performance.}, keywords = {DNS, reasoner}, author = {Hadrien Hours and Ernst Biersack and Patrick Loiseau and Alessandro Finamore and Marco Mellia} } @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} }