Gene Cheunga
gene-cs.cheung@hp.com |
Puneet Sharmab
puneet@hpl.hp.com |
Sung-Ju Leeb
sjlee@hpl.hp.com |
Abstract
Modern mobile devices are multi-homed with WLAN and WWAN communication interfaces. In a community of nodes with such multihomed devices---locally inter-connected via high-speed WLAN but each globally connected to larger networks via low-speed WWAN, striping high-volume traffic from remote large networks over a bundle of low speed WWAN links can overcome the bandwidth mismatch problem between WLAN and WWAN. In our previous work, we showed that a packet striping system for such multi-homed devices --- a mapping of delay-sensitive packets by an intermediate gateway to multiple channels using combination of retransmissions (ARQ) and forward error corrections (FEC)--- can dramatically enhance the overall performance. In this paper, we improve upon a previous algorithm in two respects. First, by introducing two-tier dynamic programming tables to memoize computed solutions, packet striping decisions translate to simple table lookup operations given stationary network statistics. Doing so drastically reduces striping operation complexity. Second, new weighting functions are introduced into the hybrid ARQ/FEC algorithm to drive the long-term striping system evolution away from pathological local minima that are far from the global optimum. Results show the new algorithm performs efficiently and gives improved performance by avoiding local minima compared to the previous algorithm.