Software Seminar
Thomas Bartold
THE UNIVERSITY OF MICHIGAN
Computer Science & Engineering Division
Software Seminar
MetaComm: a Meta-Directory for Telecommunications
Dr. Daniel Lieuwen
Bell Labs, Lucent Technology
Abstract:
A great deal of corporate data is buried in network devices --- such as PBX
messaging/email platforms, and data networking equipment --- where it is
difficult to access and modify. Typically, the data is only available to the
device itself for its internal purposes and it must be administered using
either a proprietary interface or a standard protocol against a proprietary
schema. Since some of this data is neededin multiple devices as well as in
applications like corporate directories and provisioning systems, it is
often re-entered manually and partially replicated in different devices in
quite different formats. As a result, there is a great deal of expense
involved in performing updates and the risk of inconsistencies across
devices. One of the great promises of the
Directory Enabled Networking (DEN) initiative is the ability to read and
modify standardized objects through a standard protocol (e.g., LDAP) for
many administrative tasks. DEN provides a common schema with which to manage
complex converged voice/data policy-based networks. To remain viable in
converged scenarios, the current family of voice products must play into the
directory-based management paradigm developed for the data world.
MetaComm integrates data from multiple devices into a meta-directory,
allowing user information to be modified through a directory using the LDAP
protocol as well as directly through two legacy devices: a Definity (R) PBX
and a voice messaging system. In order to prevent data inconsistencies,
updates to any system must be reflected appropriately in all the other
systems. In this scenario, where data integration is performed across
several systems with no triggers and with extremely weak typing and
transactional support, maintaining consistency poses many challenges. This
talk describes how these issues are addressed in MetaComm. We also give a
detailed description of the system's internals, and our experiences in
building the system.
Biosketch:
Daniel F. Lieuwen is a Member of Technical Staff in the Database Systems
Research Department at Bell Laboratories, a division of Lucent Technologies.
His early research focus was on object-oriented databases (particularly
Ode), main-memory databases, materialized views, and active databases, but
he is currently branching out into topics related to databases-on-the-web.
This has led to work on LTAP (Lightweight Trigger Access Protocol), a
standards compliant gateway to provide trigger services to LDAP users.
Lieuwen attended Calvin College, Grand Rapids, Michigan where he studied
mathematics and computer science (and a fair bit of German). He received the
M.S. and Ph.D. degrees in Computer Science from the University of
Wisconsin-Madison. He joined Bell Laboratories in 1992.
Friday, October 13, 2000
Time 10:30 AM - 12:00 PM
Room #1005 EECS
*********************
Tamara Tessier
Research Secretary III
University of Michigan
Software Systems Laboratory
PH: (734) 764-9401
Fax: (734) 763-8094
*********************
Thomas Bartold
THE UNIVERSITY OF MICHIGAN
Computer Science & Engineering Division
Software Seminar
Understanding the Large-Scale Dynamics of Internet Routing Protocols
Dr. Craig Labovitz
Microsoft Research
Abstract:
In this talk, we will explore many of myths that surround the
fault-tolerance and reliability of the Internet backbone infrastructure. For
example, could the Internet really survive a nuclear war? Based on several
years of experimental Internet infrastructure measurements, we will
demonstrate that Internet backbone routing does not posses many of its
traditionally assumed capabilities, including fast re-routing after
failures, and improved fault-tolerance through redundant provider
connections. Finally, we will provide insight into both the origins and
impact of routing path failures in the Internet.
Biosketch:
Craig Labovitz is a research scientist at Microsoft Research. His current
research focus includes Internet reliability/scalability issues and
Microsoft's next generation network services (.Net). Before joining MSR in
1999, he spent eight years at Merit Network, Inc. working on projects
ranging from the NSFNet backbone to research on Internet routing and
performance.
He received his MSE and PhD from the University of Michigan.
Tuesday, October 3, 2000
Time 1:30 - 3:00 PM
Room TBA