1 / 4

Overview of Channel Usage Change

Overview of Channel Usage Change. Authors:. Date: 2008-09-02. Situation. Solving service differentiation for smart phones and laptops (major users of bidirectional voice, video and data) is an important problem. The default EDCA were chosen:

adriananorman
Download Presentation

Overview of Channel Usage Change

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Overview of Channel Usage Change • Authors: • Date: 2008-09-02 Hart et al (Cisco Systems)

  2. Situation • Solving service differentiation for smart phones and laptops (major users of bidirectional voice, video and data) is an important problem. • The default EDCA were chosen: • To provide service differentiation between management traffic, “voice”, “video”, “best effort” etc • To provide 11e best effort traffic with the same level of priority as legacy traffic Hart et al (Cisco Systems)

  3. Problem • It turns out that the default EDCA parameters are poorly chosen for dense environments (e.g. enterprise environments) with stringent voice and video QoS requirements. • Accordingly, in these environments, EDCA parameters for BE and BK are typically advertised with larger backoffs in order to enable greater service differentiation. • Although larger backoffs may appear to waste medium time, experience indicates that this more than pays off for itself in terms of reduced collisions and greater QoS. • Presently IBSS (and DLS) STAs cannot take advantage of this prior knowledge Hart et al (Cisco Systems)

  4. Solution • 08/1095 • Send EDCA Parameter Set within Channel Usage frames, and reuse the EDCA Parameter Set sent in probe requests • Since this is the same IE as sent in probe requests, it offers IBSS (and DLS) STAs the same right to access the channel as associated clients • No reduction in service quality. • This could introduce a new DoS attack from fake APs advertising bogus EDCA parameters to degrade nearby IBSS (and DLS) STAs. • For this reason it appears as a hint, and IBSS (and DLS) STAs are free to determine the reliability of the hint (e.g. did the hint come from my associated AP?) and to follow or to disregard the hint. Hart et al (Cisco Systems)

More Related