TY - GEN
T1 - An adaptive optimized RTO algorithm for multi-homed wireless environments
AU - Fallon, Sheila
AU - Jacob, Paul
AU - Qiao, Yuansong
AU - Murphy, Liam
PY - 2009
Y1 - 2009
N2 - As a transport layer protocol SCTP uses end to end metrics, such as Retransmission Time Out (RTO), to manage mobility handover. Our investigation illustrates that Wireless LAN (WLAN) mobility causes continuously increased Round Trip Times (RTT) resulting from 802.11 MAC retransmissions, regardless of the service specified by upper layers. We present scenarios where the current understanding of SCTP switchover aggressiveness is invalid; spurious failovers together with excessive RTO result in new forms of receiver buffer blocking communication failure. Given wireless mobility performance issues, together with the ambiguity of end to end metrics, we propose an Adaptive Optimized RTO algorithm for wireless Access Networks (AORAN) which uses local as well as end to end metrics to manage mobility. AORAN measures RTT between the mobile node and Access Point (AP) to calculate wireless and Internet RTO subcomponents. We also show binary exponential backoff has negative effects on SCTP with increased wireless RTT; AORAN introduces a decision mechanism which implements backoff on RTO subcomponents only when appropriate.
AB - As a transport layer protocol SCTP uses end to end metrics, such as Retransmission Time Out (RTO), to manage mobility handover. Our investigation illustrates that Wireless LAN (WLAN) mobility causes continuously increased Round Trip Times (RTT) resulting from 802.11 MAC retransmissions, regardless of the service specified by upper layers. We present scenarios where the current understanding of SCTP switchover aggressiveness is invalid; spurious failovers together with excessive RTO result in new forms of receiver buffer blocking communication failure. Given wireless mobility performance issues, together with the ambiguity of end to end metrics, we propose an Adaptive Optimized RTO algorithm for wireless Access Networks (AORAN) which uses local as well as end to end metrics to manage mobility. AORAN measures RTT between the mobile node and Access Point (AP) to calculate wireless and Internet RTO subcomponents. We also show binary exponential backoff has negative effects on SCTP with increased wireless RTT; AORAN introduces a decision mechanism which implements backoff on RTO subcomponents only when appropriate.
KW - Failover
KW - Mobility
KW - Multi-homing
KW - Receiver buffer blocking
KW - SCTP
UR - http://www.scopus.com/inward/record.url?scp=69849107177&partnerID=8YFLogxK
U2 - 10.1007/978-3-642-02118-3_12
DO - 10.1007/978-3-642-02118-3_12
M3 - Conference contribution
AN - SCOPUS:69849107177
SN - 3642021174
SN - 9783642021176
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 133
EP - 145
BT - Wired/Wireless Internet Communications - 7th International Conference, WWIC 2009, Proceedings
T2 - 7th International Conference on Wired/Wireless Internet Communications, WWIC 2009
Y2 - 27 May 2009 through 29 May 2009
ER -