(TCP congestion control over a live UMTS network [http://c3lab.poliba.it/images/2/21/Umts_tcp_stacks_170407.pdf])
(TCP congestion control over a live UMTS network [http://c3lab.poliba.it/images/2/21/Umts_tcp_stacks_170407.pdf])
Riga 13: Riga 13:
 
* packet loss ratios
 
* packet loss ratios
 
* number of timeouts
 
* number of timeouts
We present here using cumulative distribution function plots the main results of the investigation.
+
We show cumulative distribution function plots to illustrate the main results of our investigation.
 +
 
 +
==Goodput==
 +
[[Immagine:goodput_1_flow_downlink.png]]
 +
[[Immagine:goodput_2_flows_downlink.png]]
 +
[[Immagine:goodput_4_flows_downlink.png]]
 +
[[Immagine:channel_utilization_downlink.png]]

Revisione 16:03, 17 Apr 2007

TCP congestion control over a live UMTS network [1]

We have performed an extensive campaign of measurements that involved around 3000 flows and more than 40 hours of measurements using three different TCP stacks:

  • TCP NewReno: the congestion control algorithm standardized by IETF
  • TCP BIC: the default congestion control algorithm adopted by the Linux o.s.
  • TCP Westwood+: available in the Linux kernel (both 2.4 and 2.6 kernels).

The experimental evaluation has been carried out by accessing the public Internet using an UMTS card (see figure below).

UmtsTestbed.png

The following instantaneous variable measurements have been collected by using the libnetmeas library:

  • Goodput
  • Round Trip Time
  • packet loss ratios
  • number of timeouts

We show cumulative distribution function plots to illustrate the main results of our investigation.

Goodput

Goodput 1 flow downlink.png Goodput 2 flows downlink.png Goodput 4 flows downlink.png Channel utilization downlink.png

TCP congestion control over a live UMTS network [1][edit]

We have performed an extensive campaign of measurements that involved around 3000 flows and more than 40 hours of measurements using three different TCP stacks:

The experimental evaluation has been carried out by accessing the public Internet using an UMTS card (see figure below).

UmtsTestbed.png

The following instantaneous variable measurements have been collected by using the libnetmeas library:

We show cumulative distribution function plots to illustrate the main results of our investigation.

Goodput[edit]

Goodput 1 flow downlink.png Goodput 2 flows downlink.png Goodput 4 flows downlink.png Channel utilization downlink.png