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On Shared Risk Link Group Optimization (Invited)
Guangzhi Li, Dongmei Wang, Timothy Gallivan, Robert Doverspike
Journal of optical communication networks,
2012.
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[BIB]
IEEE Copyright
This version of the work is reprinted here with permission of IEEE for your personal use. Not for redistribution. The definitive version was published in 2012 , Volume $vol, 2012-09-13
{Abstract— Shared Risk Link Groups (SRLGs) have been investigated during the past 10 years due to optical network innovation and deployment. Dense Wavelength Division Multiplexing (DWDM) technology has significantly increased the data transmission capability per fiber. Service providers build their overlay networks, such as IP networks, on top of optical networks and all optical networks are built over some combination of DWDM equipment and fibers. If there is a single DWDM system outage or fiber outage, the set of overlay network links dependent on the failed resource would all fail at the same time. The set of links failed by a common resource outage is called a shared risk link group (SRLG). SRLGs have been designed and implemented in many network planning tools and some network routing protocols. A single SRLG represents one potential outage (or failure mode) and a large service provider’s network could easily contain tens of thousands of failure modes. The greater the number of SRLGs, the more difficult it is to attain good performance from planning tools (like routers) whose computations are dependent on the number of SRLGs. For some routing protocols using SRLG information, the situation becomes even worse because a routing protocol may have space constraints to hold a limited number of SRLGs. These issues create a challenge to optimize the SRLG calculations such that the SRLG-related functions are not impacted or the impacts to the SRLG-related functions are limited. This paper takes a closer look at the SRLG optimization issue and proposes algorithms for how to reduce the number of SRLGs for different applications. }
On Shared Risk Link Group Optimization
Guangzhi Li, Dongmei Wang, Robert Doverspike, Timothy Gallivan
OFCNFOEC 2012,
2012.
[LINK]
[BIB]
IEEE Copyright
This version of the work is reprinted here with permission of IEEE for your personal use. Not for redistribution. The definitive version was published in OFCNFOEC 2012. , 2012-03-04, http://www.ofcnfoec.org/home.aspx
{this paper takes a closer look at the shared risk link group (SRLG) optimization issue and proposes algorithm on how to reduce the size of the SRLGs for different applications with correctness proofs.}
SRLG-Diverse Routing of Multiple Circuits in a Heterogeneous Optical Transport Network
Dahai Xu, Guangzhi Li, Byrav Ramamurthy, Angela Chiu, Dongmei Wang, Robert Doverspike
International Workshop on Design of Reliable Communication Networks (DRCN) 2011,
2011.
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IEEE Copyright
This version of the work is reprinted here with permission of IEEE for your personal use. Not for redistribution. The definitive version was published in International Workshop on Design of Reliable Communication Networks (DRCN) 2011. , 2011-10-12
{Network planners are often requested to provision multiple physically-diverse high-speed circuits over a large carrier's core (inter-city) DWDM network, which consists of multiple layers and heterogeneous vendor systems. Optimally provisioning such circuits while avoiding shared risk link group (SRLG) failures is an NP-hard problem. In this paper, we propose a novel hybrid two-step approach: pre-processing with Integer Linear Programming (ILP) for diverse routing and post-processing for regenerator placement and wavelength assignment. This approach has been implemented in a prototype network planning tool. According to our experiments, most of the cases for a typical large carrier's core transport network can be solved within 1 minute, even with tens of thousands of binary decision variables, which allows interactive use by network planners.}
IP Backbone Design for Multimedia Distribution: Architecture and Performance
Guangzhi Li, Robert Doverspike, Kadangode Ramakrishnan, Dongmei Wang, Kostas Oikonomou
2006.
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[BIB]
{Multimedia distribution, especially broadcast TV distribution over an IP network requires high bandwidth combined with tight latency and loss constraints, even under failure conditions. Due to high bandwidth requirements of broadcast TV distribution, use of IP-based multicast to distribute TV content is needed for capacity efficiency. The protection and restoration mechanisms currently adopted in IP backbones use either IGP re-convergence or some form of Fast Reroute. The IGP re-convergence mechanism is too slow for real-time multimedia distribution while a drawback of fast reroute is that since they re-route traffic on a link-basis (instead of end-to-end) they can suffer traffic overlap during failures. Here traffic overlap is defined as the same traffic passing through the same link along the same direction more than once, which requires more link capacity. We propose a method that interacts with Fast Reroute and multicast to minimize traffic overlap during failures. We also present an algorithm for link-weight setting that avoids traffic overlap for any single link failure. Performance analysis shows that the proposed method improves network service availability and significantly reduces the impact of failure events. version 2 record added in error; please see version 1 for paper. }
A GMPLS based control plane testbed for dnd-to-end services
Guangzhi Li, Jennifer Yates, Dongmei Wang, Panagiotis Sebos, Joel Gottlieb, Albert Greenberg
2005.
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IEEE Copyright
Copyright (1992-2009) IEEE. The IEEE owns the copyright to material that is published by the IEEE. Personal use of this material is permitted. However, permission to reprint / republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Please read the full
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Efficient restoration capacity design in MPLS networks
Guangzhi Li, Dongmei Wang, Jennifer Yates, Charles Kalmanek, Robert Doverspike
2004.
[DOC]
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Efficient Segment-by-Segment Restoration
Dongmei Wang, Guangzhi Li, Jennifer Yates, Charles Kalmanek
2004.
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[BIB]
Economic Analysis of IP/Optical Network Architectures
Guangzhi Li, Dongmei Wang, Charles Kalmanek, Jennifer Yates, Robert Doverspike
2004.
[PDF]
[BIB]
IEEE Copyright
Copyright (1992-2009) IEEE. The IEEE owns the copyright to material that is published by the IEEE. Personal use of this material is permitted. However, permission to reprint / republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Please read the full
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Detail study of IP/Reconfigurable Optical Network Architectures
Guangzhi Li, Dongmei Wang, Jennifer Yates, Robert Doverspike, Charles Kalmanek
2004.
[DOC]
[BIB]
IEEE Copyright
Copyright (1992-2009) IEEE. The IEEE owns the copyright to material that is published by the IEEE. Personal use of this material is permitted. However, permission to reprint / republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Please read the full
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Congestion control in resilient packet rings
Dongmei Wang, Kadangode Ramakrishnan, Charles Kalmanek, Robert Doverspike, Aleksandra Smiljanic
7th INFORMS Telecommunications Conference,
2004.
[BIB]
{}
Efficient algorithm for OSPF subnet aggregation
Guangzhi Li, Dongmei Wang, Jennifer Yates, Charles Kalmanek, Aman Shaikh
2003.
[BIB]
IEEE Copyright
Copyright (1992-2009) IEEE. The IEEE owns the copyright to material that is published by the IEEE. Personal use of this material is permitted. However, permission to reprint / republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Please read the full
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Ultra-fast IP link and interface provisioning with applications to IP restoration
Panagiotis Sebos, Jennifer Yates, Guangzhi Li, Dongmei Wang, Monica Lazer, Albert Greenberg, Rubenstein Dan
2002.
[DOC]
[BIB]
Control plane design for reliable optical networks
Guangzhi Li, Jennifer Yates, Charles Kalmanek, Dongmei Wang
2002.
[BIB]
IEEE Copyright
Copyright (1992-2009) IEEE. The IEEE owns the copyright to material that is published by the IEEE. Personal use of this material is permitted. However, permission to reprint / republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Please read the full
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Bandwidth Management For MPLS Fast Rerouting,
Tue Jun 26 16:10:50 EDT 2012
Certain exemplary embodiments provide a method comprising: in a network at a node located on a label switched path: selecting a backup path to respond to a failure; and for each link along the backup path, reserving a backup bandwidth, wherein the backup bandwidth is sufficient to reroute traffic around the failure.
Method For Restoration And Normalization In A Mesh Network,
Tue Jul 05 16:05:39 EDT 2011
The present invention is directed to methods for signaling that enable bandwidth reservation, path restoration, path normalization, and path removal in a mesh network that supports shared mesh restoration.
System And Method For Restoration In A Multimedia IP Network,
Tue Nov 09 15:04:59 EST 2010
Disclosed herein are systems, methods, and computer readable media for modifying IP backbone link weights such that multicast traffic and unicast traffic will not travel on a same path between nodes. The method comprises assigning link weights to nodes within an IP backbone such that multicast forwarding paths and unicast forwarding paths are failure disjoint, and delivering undelivered multicast packets using IP unicast encapsulation to the loopback address of next hop router on a multicast tree upon link/interface failure.
Method For Restoration And Normalization In A Mesh Network,
Tue Jan 26 15:03:16 EST 2010
The present invention is directed to methods for signaling that enable bandwidth reservation, path restoration, path normalization, and path removal in a mesh network that supports shared mesh restoration.
Method And Apparatus For Automatically Constructing Application Signatures,
Tue Nov 17 16:08:10 EST 2009
The present invention relates to a method and system for the automated construction of application signatures. In one example, an approach for automatically constructing accurate signatures for individual applications, with minimal human involvement or application domain knowledge, is provided. Given a training data set containing the application traffic, the Automated Construction of Application Signatures (ACAS) system uses a combination of statistical, information theoretic and combinatorial optimization techniques, to derive application-layer signatures from the payload of packets, e.g., IP packets. Evaluations with a range of applications demonstrate that the derived signatures are very accurate and scale to identifying a large number of flows in real time on high-speed links.
System And Method For Routing Packet Traffic,
Tue Nov 03 16:08:08 EST 2009
A system and method for routing packet traffic is disclosed. A system that incorporates teachings of the present disclosure may include, for example, a router having a routing element that routes packet traffic according to Internal Gateway Protocol (IGP) weights that prevent multicast packet traffic and unicast packet traffic from occupying a common unidirectional link. Other embodiments are disclosed.
