Thursday, June 28, 2007

TCP ACK Congestion Control and Filtering for Fairness Provision in hte Uplink of IEEE 802.11 Infrastructure Basic Service Set

Feyza Keceli, Inanc Inan, and Ender Ayanoglu

The authors separate the TCP downlink acks in a different queue. By wisely scheduling those acks, they obtain fairness among the uplink flows.

Saturation Throughput Analysis of the 802.11e Enhanced Distributed Channel Access Function

Inanc Inan, Feycza Keceli, and Ender Ayanoglu

Again, an extended Markov chain allows the inclusion of the AIFS and CWmin in the throughput calculation. It makes emphasis in that in the slots immediatly after a busy slot there are different collision probabilities, depending on the AIFS configurations of the stations

Wednesday, June 27, 2007

conferences for woman (wireless open metropolitan access networks)

LANMAN -over
WMASH -dead
WCNC - Las Vegas, submission due to September
MWCN - over
INFOCOM . deadline July 2, rejection november 12
ACCESSNETS - over
QoSIP 2008 - over
QSHINE Over
ISWCS Over
MOBIQUITOUS Over
WiNTECH Over
IEEE LCN

The list:
http://wireless.cs.tku.edu.tw/~seanwang/html/research.html

Monday, June 25, 2007

Linux for suits: Migrating a mentality

Doc Searls

The author defends that network should be treated as a facility, just as electricity, to support the rest of the economy.

open access networks

@article{edvardsen:oan,
title={{Open access networks}},
author={Edvardsen, E. and Eskedal, T.G. and Arnes, A.},
journal={Converged Networking}
}

A completely different deffinition of the OAN.

Towards an Economic Framework for Network Neutrality Regulation

Barbara van Schewick

A forty-page analysis of the network neutrality discussion. The network providers have incentives to discriminate, even in the case that they do not hold a monopoly position. This discrimination would have disastrous impact on the innovation in the application level and therefore network neutrality should be enforced by regulators.

Wednesday, June 20, 2007

100+ VoIP Calls on 802.11b: The Power of Combining Voice Frame Aggregation and Uplink-Downlink Bandwidth Control in Wireless LANs

Sangki Yun, Hyogon Kim, Heejo Lee, and Inhye Kang

Very interesting... so many things to summarize! Deals with uplink/downlink unfairness aspects, packet aggregation at the MAC level, E-model.

The key idea is that the channel access is the main overhead in VoIPoWLAN. Thus aggregating packets belonging to the same call at the mac level drastycally boosts the performance.

Tuesday, June 19, 2007

ensalada grega

Tomàtiga
Formatge Feta
Olives
Orenga
Oli

Performance Analysis of the WLAN-First Scheme in Cellular WLAN Interworking

Song, Jiang, Zhuang

I've been studying IMS-WLAN interworking and there is people in the group focusing on CAC, VoIP QoS in WLAN, and capacity studies in heterogeneous (voice/data) scenarios. Thus this paper promises to bridge this topics.

The different behaviour/capacity of cell and wlan, and the different behaviour of users in both environments (assumed outdoor and indoor) makes it difficult to decide how to assign user to one or the other technology. Since the performance of VoIP on wlan is poor, it seems natural to as many data sessions as possible to the wlan.

Monday, June 18, 2007

wlan sharing - alternatives

This are different alternatives to share wlan.

- Neutral Operator (kth, barcelona...)
- Tunneling (Urbino)
- IMS-like (involving tunnels)
- Radius relay (Eduroam, WISPr)
- Wilmagate (Like Radius relay, without radius)
- Multiple ssid, multiple wlan
- WLAN differentiation using capwap

Maybe it would be interesting to review all the existing alternatives and compare thems in terms of

- convenince
- security
- matureness
- scalability

3GPP TS 23.234

Wireless Local Area Network interworking system description

Describes how a WLAN can be used to access 3gpp ims ps domain. I am specially interested in policy/QoS aspects.

Wednesday, June 13, 2007

MAC Access Delay of IEEE 802.11 DCF

Taka Sakurai, Hai L. Vu

Even though 802.11 dcf has been extensively studied, it seem that there is still room for more research. In this case, building up previous work by Kwak Song and Miller, the access delay is calculated, obtaining more accurate results than other authors.

Tuesday, June 5, 2007

Fairness Provision in the IEEE 802.11e Infrastructure Basic Service Set

Inanc Inan, Feyza Keceli, and Ender Ayanoglu

Closely related to our current work, they actually stepped forward. However, it's reconforting to see that other people focus on the same research, it makes you think that it's not completely worthless.

The authors highlight the fact that the default values for the EDCA are suboptimum. Moreover, no fixed set of parameters can fight the uplink/downlink fairness. They provide an analytical model and an extensive set of simulated scenarios involving TCP and UDP traffic.