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TKN - Telecommunication Networks Group TU-Berlin
Head of Group: Prof. Adam Wolisz Faculty of Electrical Engineering and Computer Science

MOMBASA Software Environment
Performance measurements
Links and papers related to MOMBASA


MOMBASA stands for 'MObility support - a Multicast-BASed Approach'. MOMBASA utilizes IP-style multicast to support network-level mobility in IP-based networks. In this approach the basic multicast functionality (location-independent addressing and routing, group creation, subscription, unsubscription) is complemented by functionality which are required for mobility support (registration, etc,) and are useful due to performance reasons. In comparison to the classical approach for mobility support with IP address translation and indirect routing (e.g. Mobile IP), MOMBASA has three main advantages:

  • Rerouting for handover is done in a network node where the path to the old and from the new access points diverge (and not in a software agent in the mobile's home network as in the Mobile IP approach).
  • In principle, no "handover-specific" signaling and infrastructure is required, instead multicast is reused for mobility purposes.
  • MOMBASA minimizes the handover latency. In the utmost case packets are distributed in advance to potential new access points which buffer the packets. In this case the usage of multicast provides the efficient distribution of data to multiple access points.
More about MOMBASA (ps, pdf)



For evaluation and comparison of selected multicast approaches an experimental testbed is setup.

 Its main components are:

  •        a subnetwork unaware of mobility mechanisms where the corresponding host is located,
  •        a WAN emulator, basically emulating the traffic- and transport characteristics of the Internet,
  •        a Gateway router to the visited domain,
  •        some routers inside the visited domain,
  •        cell switches (WUGS),
  •        some access points with different technologies (IEEE 802.11, IrDA), and
  •        some mobile hosts.
In the testbed the MOMBASA Software Environment is used.


MOMBASA Software Environment

A subset of the MOMBASA functionality has been realized as an experimental platform. The main components of the MOMBASA Software Environment are implemented for the Linux operating system in C++ as daemons running in user space.
  • Download the MOMBASA Software Environment ( html )
  • Online documentation of the source code ( html )
  • Protocol specification of the MOMBASA Software Environment ( ps, pdf )
  • Implementation design of the MOMBASA Software Environment ( ps, pdf )
  • The conformance of the implementation with the specification was extensively tested. The test cases and the test environment are described here (ps, pdf).


    Performance measurements






    Links and papers related to MOMBASA

    General papers on multicast-based mobility

    A New Multicasting-Based Architecture for Internet Host Mobility, J. Mysore and V. Bharghavan, ACM Mobicom '97, Budapest, Hungary, September 1997. (link)
    Providing Connection-Oriented Network Services to Mobile Hosts, K. Keeton, B. Mah, S. Seshan, R. Katz, and D. Ferrari. Proceedings of the USENIX Symposium on Mobile and Location-Independent Computing, Cambridge, MA, 1993. ( ps )
    A Protocol for Seamless Communication in a Picocellular Network, R. Ghai and S. Singh, ICC'94. ( ps.gz )
    Fast and Scalable Handoffs for Wireless Internetworks, R. Cáceres and V. N. Padmanabhan, Proc. ACM MobiCom '96, November 1996. ( ps.gz )
    Vertical Handoffs in Wireless Overlay Networks, M. Stemm and R. H. Katz. ACM Mobile Networking and Applications (MONET), Special Issue on "Mobile Networking in the Internet", January 1999. ( link )
    Agent based seamless IP multicast receiver handover, J. Wu, G. Maguire, Proceedings of the IFIP Conference on Personal Wireless Communications PWC'2000, September 2000. ( pdf )
    Multicast For Mobility Protocol (MMP) For Emerging Internet Networks, A. Mihailovic, M. Shabeer, A. H. Aghvami, Proceedings of the eleventh IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC 2000), September 2000, London UK. ( pdf )
    A Multicast-based Protocol for IP Mobility Support, A. Helmy, ACM Second International Workshop on Networked Group Communication (NGC 2000), Palo Alto, November 2000. ( pdf )

    IP Multicast

    IETF Protocol-independent multicast working group ( link )
    IETF Source-specific multicast working group ( link )
    IETF Multicast & Anycast Group Membership working group (magma) ( link )
    Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification (Revised), B.. Fenner, M. Handley, H. Holbrook, I. Kouvelas, Internet Draft, WORK IN PROGRESS, July 2001. ( txt )
    Protocol-Idependent Multicast-Sparse Mode: Motivation and Architecture, S. Deering, D. Estrin, D. Farinacci, M. Handley, A. Helmy, V. Jacabson, C. Liu, P. Sharna, D. Thaler, L. Wei, Internet Draft, Expired, October 1996. ( ps.gz )
    IGMPv3 source code for Linux @ Cisco ( link )
    PIM implementation   (Open source code for Linux) ( link )
    Design and Implementation of IGMPv3 for Linux, C. Gkantsidis, Technical Report TR00-ATL-111501. ( ps )
    Testing IGMPv3 Implementations, C. Gkantsidis, S. Bhattacharyya, W. de Graaf , Technical Report TR00-ATL-111502. ( ps )
    IGMPv3 kernel implementation   (Open source code for NetBSD) ( link )
    MLDv2 host implementation ( link ) and router implementation ( link ) (Open source code for FreeBSD)
    IP Multicast Channels: EXPRESS Support for Large-scale Single-source Applications, H. Holbrook, D. Cheriton. ACM SIGCOMM'99. ( link )
    IGMP-Based multicast forwarding (IGMP Proxying) W. Fenner. ( link )
    IGMP Proxying implementation (Open source code for FreeBSD)( link )


    WU Gigabit Kit @ Washington University, St. Louis. ( link )
    A Call Model for Multipoint Communications in Switched Networks, M. Gaddis, R. Bubenik, J. DeHart, ICC'92. ( ps )
    Connection Management Software System (CMSS) Architecture, J. DeHart, Technical Report ARL95-3, January 1998. ( pdf )
    CMAP, K. Cox, J. DeHart, Technical Report ARL-94-08, July 1994. ( ps.Z )
    Connection Management Network Protocol (CMNP) Specification, J. DeHart, D. Wu, Draft, July 1996. ( ps )
    Node Controller Managed Object (NCMO) and Node Controller Communication Protocol (NCCP), D. Wu , J. DeHart, Technical Report ARL-96-03, July 1998. ( pdf )
    GBNSC: The Gigabit Network Switch Controller, D. Wu, J. DeHart, K. Cox, Technical Report ARL-94-12, July 1998. ( pdf )

    Small Group Multicast (SGM) / Explicit Multicast (XCAST)

    Xcast. ( link )
    Explicit Multicast (XCAST) project at IBM  (Open source code for IPv4). ( link )
    Xcast API based on the Internet Draft draft-ooms-xcast-basic-spec-01.txt. ( txt )
    Multiple Destination Option on IPv6 (MDO-6) KIT (Open source code for FreeBSD, NetBSD). ( link )
    XCast for IPv6 (Open source code for NetBSD). ( link )
    SGM Support in Mobile IP, J. Lee, Internet Draft, expired April 2001.


    Micro-mobility protocols for ns-2 (Cellular IP, HAWAII, Hierarchical Mobile IPv4). ( link )
    IP Mobility Support, C. Perkins, Editor, Internet RFC 2002. ( txt )
    Mobility Support in IPv6, D. Johnson, C. Perkins, Internet draft, work-in-progress. ( txt )
    Mobile IP Regional Registration, E. Gustavsson, A. Honsson, C. Perkins, Internet draft, expired.
    Hierarchical MIPv6 mobility management (HMIPv6), H. Soliman, C. Castelluccia, K. El-Malki, L. Bellier, Internet draft, work-in-progress. ( txt )
    Emcast Multicast Libraray ( link  )




    Andreas Festag, Lars Westerhoff

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