Multicast Detective - Facilitating Robust Multicast Group Join

Abstract

• Multicast is a key service for many audio and video applications, yet it continues to be a challenging Internet service to deploy. While much attention has been given to a number of problems associated with multicast, two closely related problems in particular have received almost no attention. First, there is essentially no host support for dealing with the variety of ways to join a multicast group, and second, there is a complete absence of group join success or failure feedback from the network. The lack of a straightforward way to robustly join a multicast group and then to know whether the join has been successful is possibly the biggest limitation for multicast application developers today. In this study we develop a robust solution to determine the existence and nature of multicast service in the network. We consider two options: (1) the use of existing protocol features to extract the required information, and (2) the introduction of new protocol extensions to directly query the network. Our results indicate that while a truly robust group join is possible only when there is network support, these additional changes are difficult to deploy. Our evaluation implements a proof-of-concept prototype to determine the existence and nature of the multicast service in the network.

Publications

• A. Sen Mazumder, K. Almeroth and K. Sarac, "Facilitating Robust Multicast Group Management", Network and Operating System Support for Digital Audio and Video (NOSSDAV) , Skamania, Washington, USA, June 2005.

Software Release

• The Multicast Detective is a command line tool. The beta version runs on Windows 2000 and XP operationg systems and uses the IPv4 protocol stack.

• Binaries:

• The Win32 executable: .exe [617 KB] or zipped version of .exe [137 KB]

• Source Code:

• The source code is downloadable from here
• Build Requirements:
• Microsoft C++ Compiler (The recent version is built using VC++ 6.0)
• Microsoft Platform SDK

The Multicast Detective Tests:

• The Multicast Detective uses raw socket to send and receive IGMP and ICMP packets. This means that users need administrative privileges to run the entire test suit, otherwise only first two tests can be run. The tool runs following tests:


1. Joins the NLAR Multicast Beacon Group 233.64.133.120, port 10002
2. Joins the SSM Video Group 232.4.200.19, 63.105.122.29 port 8020
3. Checks if the first-hop router is multicast capabile
4. Checks if the first-hop router is SSM capable
5. Detects if there is IGMPv2 capability to the first-hop router
6. Detects if there is IGMPv3 capability to the first-hop router
7. Detects if the first-hop router supports PIM-SM
8. Detects if the first-hop router knows about an RP


• Finally the Multicast Detective prints out a report interpreting these test results.

Feedback

• Comments, suggestions and bug reports are welcome at avijit@cs.ucsb.edu