Located at Argonne National Laboratory; 100 Mbps FastEthernet network connection
This java applet was developed to test the reliablity and operational status of your desktop computer and network connection. It does this by sending data between your computer and this remote NDT server. These tests will determine:
>> The slowest link in the end-to-end path (Dial-up modem to 10 Gbps Ethernet/OC-192)
>> The Ethernet duplex setting (full or half);
>> If congestion is limiting end-to-end throughput.
It can also identify 2 serious error conditions:
>> Duplex Mismatch
>> Excessive packet loss due to faulty cables.
We performed several throughput measures between two hosts with 10 GE interfaces, using stock TCP (Reno), Fast TCP, Scalable TCP and High Speed TCP.
The results show that there are a lot of variables to take into account to improve the performances. Some of these variables are: TCP memory settings,
window size, mtu, txqueuelen. A small change for one of their values may alter significantly the results.
This document begins with a description of the testbed and of the general settings for Sender and Receiver hosts.
In the next section we compare the best results we could get for the four different TCP stacks, using Jumbo and Standard MTUs.
The last section shows the measures obtained changing values of mtu, txqueuelens and other settings. Results are grouped by TCP stacks.
The CM is an end-to-end framework for congestion control and management, bandwidth sharing, independent of specific transport protocols (like TCP) and applications. Its end-system architecture enables logically different flows (such as multiple concurrent Web downloads, concurrent audio and video streams, etc.) to adapt to congestion, share network information, and share (varying) available bandwidth well. Rather than have each stream act in isolation and thereby adversely interact with the others, the CM maintains host- and domain-specific path information, and orchestrates all transmissions. The CM's internal algorithms ensure social and stable network behavior; its API enables a variety of applications and transport protocols to adapt to congestion and varying bandwidth. Internet traffic patterns and applications have been evolving rapidly in recent years and network congestion is becoming a problem of extreme importance. While the Internet's transport protocol, TCP, incorporates congestion control machinery and has largely been responsible for the stability of the Internet to date, two problematic trends threaten this situation:
Internet Measurement Conference 2003
Sponsored by ACM SIGCOMM and co-sponsored by USENIX
October 27-29, 2003
Miami, Florida, USA
The Internet Measurement Conference is a two and a half day event focusing on Internet measurement and analysis, following on the success of the 2001 Internet Measurement Workshop and the 2002 Internet Measurement Workshop. Submissions should contribute to the current understanding of how to collect or analyze Internet measurements, or give insight into how the Internet behaves.