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ANTI Access Network Type Inference Overview
Access networks consist of the links connecting end systems to edge routers. In practice, Ethernet, wireless LAN (WLAN), cable modem, ADSL and dialup are widely used types of access networks. Fast and accurate classification of access network type is useful for a wide range of scenarios. For instance, there is a large amount of literature on improving the performance of TCP when the last hop is a wireless link or cable connection, assuming that it is known that the last hop is a wireless link or cable connection. In peer-to-peer applications, given a group of neighbors, a peer may well choose a neighbor with an Ethernet connection over those using other connection types. Similarly, when constructing an application-level overlay, it is often desirable to choose overlay nodes with Ethernet connections over those with other connection types. We propose a simple and efficient scheme to infer the type of an access network based only on observed end-to-end measurements. Our approach utilizes the intrinsic characteristics of the various access networks and works as follows. If node A needs to determine the connection type of node B, A asks B to send a sequence of packet pairs (two back-to-back packets) to A. A then determines B's connection type based on the median and entropy of packet pair inter-arrival times from B. For Ethernet, we develop upper bounds for the median and entropy of packet pair inter-arrival times using queuing analysis. For WLAN, we derive the median and entropy values of packet pair inter-arrival times under the assumption of perfect channel conditions and a contention-free environment. The entropy and median values for a WLAN differ dramatically from those for an Ethernet connection, allowing us to distinguish between the two types of access networks based on these values. Our method to distinguish WLAN and low-bandwidth connections are based on empirical results. Extensive experiments (including 9 countries in 4 continents and 28 states in the US) show that our scheme obtains accurate classification results in a very short time (10 to 100 seconds). Experiment Coverage
Classification Results
Papers
· Classification of Access Network Types: Ethernet, Wireless LAN, ADSL, Cable Modem or Dialup? · Classification of Access Network Types: Ethernet, Wireless LAN, ADSL, Cable Modem or Dialup? |
