Achievable gains in AP Discovery

1. Achievable gains in AP Discovery Authors: Date: 2010-07-15 Marc Emmelmann, FOKUS

2. Abstract Based on the ongoing discussion in FIA SG, there requests were risen to elaborate how all phases being part of an initial link set-up could be shortened. This document presents some initial toughs on improving AP discovery, Marc Emmelmann, FOKUS

3. Network Discovery Reduce numberof channels (to 1)where APs areknown to operate No Assumptions(scan all channels),stop after 1stAPsis found Return after1st AP Responses(scan 1 channel) No Assumptions(scan all channels),find all APs Enablement at 5GHz via 2.4 GHz Expected Meanof time spent inscanning for 2.4 GHz 5 GHz 2.4 GHz 5 GHz 2.4 GHz 5 GHz 2.4 GHz 5 GHz 2.4 GHz 5 GHz Passivescanning 100 ms 1100 ms 2300 ms 550 ms 1150 ms 100 ms 50ms 50ms 50ms 50ms 95% gain 98% gain Activescanning 2 + ε ms 60 ms(x) 20 ms(y) 15 ms n/a 2 ms n/a 2 ms n/a n/a 99% gain 97% gain 11k may work, But not for initial link set-up Amendment required Amendment required Amendment required Amendment required • (x)= ca. 60 ms (rough guess, depends on deployment, i.e. on probability that there is at least one AP on a given channel) • (y) = ca. 20 ms ms (rough guess, depends on deployment, i.e. on probability that there is at least one AP on a given channel) Marc Emmelmann, FOKUS

4. References Marc Emmelmann, FOKUS