A Survey of Multicasting in Optical Burst Switched Networks: Future Research Directions
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paper_title: Optical burst switching: a new area in optical networking research

paper_content:

In this tutorial, we give an introduction to optical burst switching and compare it with other existing optical switching paradigms. Basic burst assembly algorithms and their effect on assembled burst traffic characteristics are described first. Then a brief review of the early work on burst transmission is provided, followed by a description of a prevailing protocol for OBS networks called just-enough-time (JET). Algorithms used as an OBS core node for burst scheduling as well as contention resolution strategies are presented next. Trade-offs between their performance and implementation complexities are discussed. Recent work on QoS support, IP/WDM multicast, TCP performance in OBS networks, and labeled OBS is also described, and several open issues are mentioned.
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paper_title: High-speed protocol for bursty traffic in optical networks

paper_content:

An optical backbone network based on WDM (or OTDM) technology may become an economical choice for providing future broadband services. To achieve a balance between the coarse-grain optical circuit switching (via wavelength routing) and fine- grain optical packet/cell switching, optical burst switching is proposed. We study a one-way reservation protocol called just-enough-time (JET), which is suitable for switching bursty traffic in a high speed optical backbone network. The JET protocol has two unique, integrated features, namely, the use of delayed reservation (DR) and buffered burst multiplexers (BBM). By virtue of DR, the JET protocol not only increases the bandwidth utilization, but also facilitates intelligent buffer management in BBMs, and consequently results in a high through-put. Both analysis and simulation results show that the JET protocol can significantly outperform other one-way reservation protocols lacking one or both of these features.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: WDM multicasting in IP over WDM networks

paper_content:

Supporting WDM multicasting in an IP over WDM network poses interesting problems because some WDM switches may be incapable of switching an incoming signal to more than one output interface. An approach to WDM multicasting based on wavelength-routing, which constructs a multicast forest for each multicast session so that multicast-incapable WDM switches do not need to multicast, was proposed and evaluated previously. Such an approach requires global knowledge of the WDM layer. In this paper, we study WDM multicasting in an IP over WDM network under the framework of multiprotocol label switching (MPLS) using optical burst/label switching (OBS/OLS). We propose a protocol which modifies a multicast tree constructed by distance vector multicast routing protocol (DVMRP) into a multicast forest based on the local information only.
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paper_title: QoS performance of optical burst switching in IP-over-WDM networks

paper_content:

We address the issue of how to provide basic quality of service (QoS) in optical burst-switched WDM networks with limited fiber delay lines (FDLs). Unlike existing buffer-based QoS schemes, the novel offset-time-based QoS scheme we study in this paper does not mandate any buffer for traffic isolation, but nevertheless can take advantage of FDLs to improve the QoS. This makes the proposed QoS scheme suitable for the next generation optical Internet. The offset times required for class isolation when making wavelength and FDL reservations are quantified, and the upper and lower bounds on the burst loss probability are analyzed. Simulations are also conducted to evaluate the QoS performance in terms of burst loss probability and queuing delay. We show that with limited FDLs, the offset-time-based QoS scheme can be very efficient in supporting basic QoS.
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paper_title: Terabit burst switching

paper_content:

Demand for network bandwidth is growing at unprecedented rates, placing growing demands on switching and transmission technologies. Wavelength division multiplexing will soon make it possible to combine hundreds of gigabit channels on a single fiber. This paper presents an architecture for Burst Switching Systems designed to switch data among WDM links, treating each link as a shared resource rather than just a collection of independent channels. The proposed network architecture separates burst level data and control, allowing major simplifications in the data path in order to facilitate all-optical implementations. To handle short data bursts efficiently, the burst level control mechanisms in burst switching systems must keep track of future resource availability when assigning arriving data bursts to channels or storage locations. The resulting Lookahead Resource Management problems raise new issues and require the invention of completely new types of high speed control mechanisms. This paper introduces these problems and describes approaches to burst level resource management that attempt to strike an appropriate balance between high speed operation and efficiency of resource usage.
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paper_title: On fundamental issues in IP over WDM multicast

paper_content:

As WDM technology matures, IP over WDM multicast will become a challenging new topic. Supporting multicast at the WDM layer provides additional advantages, but also raises many new issues that do not exist in IP multicast. For example, the limitation on the light splitting capability of switches is one major difficulty in WDM multicast, and in addition, the limitations on both the wavelength conversion capability and optical buffer space may affect multicast routing as well. In this paper, we focus on the IP over WDM multicast routing problem, i.e. how to construct multicast trees at the WDM layer based on IP multicast routing protocols. More specifically, we study how label switched paths for optical label switching can be set up for multicast traffic. We propose two approaches, one without modification of existing IP multicast routing protocols, and the other with modification of existing IP multicast routing protocols.
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paper_title: Assembling TCP/IP packets in optical burst switched networks

paper_content:

Optical burst switching (OBS) is a promising paradigm for the next-generation Internet infrastructure. We study the performance of TCP traffic in OBS networks and in particular, the effect of assembly algorithms on TCP traffic. We describe three assembly algorithms in this paper and compare them using the same TCP traffic input. The results show that the performance of the proposed adaptive-assembly-period (AAP) algorithm is better than that of the min-burstlength-max-assembly-period (MBMAP) algorithm and the fixed-assembly-period (FAP) algorithm in terms of goodput and data loss rate. The results also indicate that burst assembly mechanisms affect the behavior of TCP in that the assembled TCP traffic becomes smoother in the short term, and more suitable for transmission in optical networks.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: On fundamental issues in IP over WDM multicast

paper_content:

As WDM technology matures, IP over WDM multicast will become a challenging new topic. Supporting multicast at the WDM layer provides additional advantages, but also raises many new issues that do not exist in IP multicast. For example, the limitation on the light splitting capability of switches is one major difficulty in WDM multicast, and in addition, the limitations on both the wavelength conversion capability and optical buffer space may affect multicast routing as well. In this paper, we focus on the IP over WDM multicast routing problem, i.e. how to construct multicast trees at the WDM layer based on IP multicast routing protocols. More specifically, we study how label switched paths for optical label switching can be set up for multicast traffic. We propose two approaches, one without modification of existing IP multicast routing protocols, and the other with modification of existing IP multicast routing protocols.
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paper_title: Control architecture in optical burst-switched WDM networks

paper_content:

Optical burst switching (OBS) is a promising solution for building terabit optical routers and realizing IP over WDM. In this paper, we describe the basic concept of OBS and present a general architecture of optical core routers and electronic edge routers in the OBS network. The key design issues related to the OBS are also discussed, namely, burst assembly (burstification), channel scheduling, burst offset-time management, and some dimensioning rules. A nonperiodic time-interval burst assembly mechanism is described. A class of data channel scheduling algorithms with void filling is proposed for optical routers using a fiber delay line buffer. The LAUC-VF (latest available unused channel with void filling) channel scheduling algorithm is studied in detail. Initial results on the burst traffic characteristics and on the performance of optical routers in the OBS network with self-similar traffic as inputs are reported in the paper.
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paper_title: Constrained multicast routing in WDM networks with sparse light splitting

paper_content:

As WDM technology matures and multicast applications become increasingly popular, supporting multicast at the WDM layer becomes an important and yet challenging topic. In this paper, we study constrained multicast routing in WDM networks with sparse light splitting, i.e., where some switches are incapable of splitting light (or copying data in the optical domain). Specifically, we propose four WDM multicast routing algorithms, namely, Re-route-to Source, Re-route-to-Any, Member-First, and Member-Only. Given the network topology, multicast membership information, and light splitting capability of the switches, these algorithms construct a source-based multicast light-forest (consisting one or more multicast trees) for each multicast session. The performance of these algorithms are compared in terms of the average number of wavelengths used per forest (or multicast session), average number of branches involved (bandwidth) per forest as well as average number of hops encountered (delay) from a multicast source to a multicast member.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: Evaluation of multicast schemes in optical burst-switched networks: the case with dynamic sessions

paper_content:

In this paper, we evaluate the performance of several multicast schemes in optical burst-switched WDM networks taking into accounts the overheads due to control packets and guard bands (Gbs) of bursts on separate channels (wavelengths). A straightforward scheme is called Separate Multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to Gbs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called Multiple Unicasting (M-UCAST). The third scheme is called Tree-Shared Multicasting (TS-MCAST) wehreby multicast traffic belonging to multiple multicast sesions can be mixed together in a burst, which is delivered via a shared multicast tree. In [1], we have evaluated several multicast schemes with static sessions at the flow level. In this paper, we perform a simple analysis for the multicast schemes and evaluate the performance of three multicast schemes, focusing on the case with dynamic sessions in terms of the link utilization, bandwidth consumption, blocking (loss) probability, goodput and the processing loads.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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paper_title: Distributed shared multicast tree construction protocols for tree-shared multicasting in OBS networks

paper_content:

Tree-shared multicasting in OBS networks can achieve bandwidth savings, less processing load, and lower burst blocking (loss) probability. In this paper, we propose several distributed shared multicast tree construction protocols, namely greedy-prune, non-member-join, all-member-join, closest-member on-tree (CMOT), and closest-node on-tree (CNOT), for tree-shared multicasting in OBS networks. For performance comparison, we also consider an optimal shared tree which is modeled as Steiner minimal tree. We evaluate the proposed protocols using simulations in terms of cost of the shared tree to the optimal shared tree. Simulations show that the CNOT and CMOT protocols outperform the other three proposed protocols in terms of the cost of the shared tree, and perform close to cost of the optimal shared tree.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: On a new multicasting approach in optical burst switched networks

paper_content:

We introduce a new multicasting approach, called tree-shared multicast (TS-MCAST), in order to alleviate overheads due to control packets and guard bands associated with data bursts when transporting multicast IP traffic in optical burst-switched WDM networks. We describe three tree sharing strategies and discuss implementation issues in constructing shared multicast trees for supporting TS-MCAST. Finally, we show the efficiency of TS-MCAST using simulation results.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: On a new multicasting approach in optical burst switched networks

paper_content:

We introduce a new multicasting approach, called tree-shared multicast (TS-MCAST), in order to alleviate overheads due to control packets and guard bands associated with data bursts when transporting multicast IP traffic in optical burst-switched WDM networks. We describe three tree sharing strategies and discuss implementation issues in constructing shared multicast trees for supporting TS-MCAST. Finally, we show the efficiency of TS-MCAST using simulation results.
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paper_title: Tree-shared multicast in optical burst-switched WDM networks

paper_content:

In this paper, we propose a new multicast scheme called tree-shared multicasting (TS-MCAST) in optical burst-switched wavelength-division-multiplexing networks, taking into consideration overheads due to control packets and guard bands (GBs) associated with data bursts. In TS-MCAST, multicast traffic belonging to multiple multicast sessions from the same source-edge node to possibly different destination-edge nodes can be multiplexed together in a data burst, which is delivered via a shared multicast tree. To support TS-MCAST, we propose three tree-sharing strategies based on equal coverage, super coverage, and overlapping coverage, and present a simple shared multicast tree-construction algorithm. For performance comparison, we consider two other multicast schemes: separate multicasting (S-MCAST) and multiple unicasting (M-UCAST). We show that TS-MCAST outperforms S-MCAST and M-UCAST in terms of bandwidth consumed and processing load (i.e., number of control packets) incurred for a given amount of multicast traffic under the same unicast traffic load with static multicast sessions and membership.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: On a new multicasting approach in optical burst switched networks

paper_content:

We introduce a new multicasting approach, called tree-shared multicast (TS-MCAST), in order to alleviate overheads due to control packets and guard bands associated with data bursts when transporting multicast IP traffic in optical burst-switched WDM networks. We describe three tree sharing strategies and discuss implementation issues in constructing shared multicast trees for supporting TS-MCAST. Finally, we show the efficiency of TS-MCAST using simulation results.
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paper_title: Tree-shared multicast in optical burst-switched WDM networks

paper_content:

In this paper, we propose a new multicast scheme called tree-shared multicasting (TS-MCAST) in optical burst-switched wavelength-division-multiplexing networks, taking into consideration overheads due to control packets and guard bands (GBs) associated with data bursts. In TS-MCAST, multicast traffic belonging to multiple multicast sessions from the same source-edge node to possibly different destination-edge nodes can be multiplexed together in a data burst, which is delivered via a shared multicast tree. To support TS-MCAST, we propose three tree-sharing strategies based on equal coverage, super coverage, and overlapping coverage, and present a simple shared multicast tree-construction algorithm. For performance comparison, we consider two other multicast schemes: separate multicasting (S-MCAST) and multiple unicasting (M-UCAST). We show that TS-MCAST outperforms S-MCAST and M-UCAST in terms of bandwidth consumed and processing load (i.e., number of control packets) incurred for a given amount of multicast traffic under the same unicast traffic load with static multicast sessions and membership.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: On a new multicasting approach in optical burst switched networks

paper_content:

We introduce a new multicasting approach, called tree-shared multicast (TS-MCAST), in order to alleviate overheads due to control packets and guard bands associated with data bursts when transporting multicast IP traffic in optical burst-switched WDM networks. We describe three tree sharing strategies and discuss implementation issues in constructing shared multicast trees for supporting TS-MCAST. Finally, we show the efficiency of TS-MCAST using simulation results.
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paper_title: Tree-shared multicast in optical burst-switched WDM networks

paper_content:

In this paper, we propose a new multicast scheme called tree-shared multicasting (TS-MCAST) in optical burst-switched wavelength-division-multiplexing networks, taking into consideration overheads due to control packets and guard bands (GBs) associated with data bursts. In TS-MCAST, multicast traffic belonging to multiple multicast sessions from the same source-edge node to possibly different destination-edge nodes can be multiplexed together in a data burst, which is delivered via a shared multicast tree. To support TS-MCAST, we propose three tree-sharing strategies based on equal coverage, super coverage, and overlapping coverage, and present a simple shared multicast tree-construction algorithm. For performance comparison, we consider two other multicast schemes: separate multicasting (S-MCAST) and multiple unicasting (M-UCAST). We show that TS-MCAST outperforms S-MCAST and M-UCAST in terms of bandwidth consumed and processing load (i.e., number of control packets) incurred for a given amount of multicast traffic under the same unicast traffic load with static multicast sessions and membership.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
---
paper_title: Efficient multicast schemes for optical burst-switched WDM networks

paper_content:

In this paper, we study several multicast schemes in optical burst-switched WDM networks taking into consideration of the overheads due to control packets and guard bands (GBs) of bursts on separate channels (wavelengths). A straightforward scheme is called separate multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to GBs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called multiple unicasting (M-UCAST). The third scheme is called tree-shared multicasting (TS-MCAST) whereby multicast traffic belonging to multiple multicast sessions can be mixed together in a burst, which is delivered via a shared multicast tree. The multicast schemes (M-UCAST and TS-MCAST) are compared with S-MCAST in terms of bandwidth consumed and processing load.
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paper_title: A fast algorithm for Steiner trees

paper_content:

Given an undirected distance graph G=(V, E, d) and a set S, where V is the set of vertices in G, E is the set of edges in G, d is a distance function which maps E into the set of nonnegative numbers and S?V is a subset of the vertices of V, the Steiner tree problem is to find a tree of G that spans S with minimal total distance on its edges. In this paper, we analyze a heuristic algorithm for the Steiner tree problem. The heuristic algorithm has a worst case time complexity of O(¦S¦¦V¦ 2) on a random access computer and it guarantees to output a tree that spans S with total distance on its edges no more than 2(1?1/l) times that of the optimal tree, where l is the number of leaves in the optimal tree.
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paper_title: Tree-shared multicast in optical burst-switched WDM networks

paper_content:

In this paper, we propose a new multicast scheme called tree-shared multicasting (TS-MCAST) in optical burst-switched wavelength-division-multiplexing networks, taking into consideration overheads due to control packets and guard bands (GBs) associated with data bursts. In TS-MCAST, multicast traffic belonging to multiple multicast sessions from the same source-edge node to possibly different destination-edge nodes can be multiplexed together in a data burst, which is delivered via a shared multicast tree. To support TS-MCAST, we propose three tree-sharing strategies based on equal coverage, super coverage, and overlapping coverage, and present a simple shared multicast tree-construction algorithm. For performance comparison, we consider two other multicast schemes: separate multicasting (S-MCAST) and multiple unicasting (M-UCAST). We show that TS-MCAST outperforms S-MCAST and M-UCAST in terms of bandwidth consumed and processing load (i.e., number of control packets) incurred for a given amount of multicast traffic under the same unicast traffic load with static multicast sessions and membership.
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paper_title: Evaluation of multicast schemes in optical burst-switched networks: the case with dynamic sessions

paper_content:

In this paper, we evaluate the performance of several multicast schemes in optical burst-switched WDM networks taking into accounts the overheads due to control packets and guard bands (Gbs) of bursts on separate channels (wavelengths). A straightforward scheme is called Separate Multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to Gbs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called Multiple Unicasting (M-UCAST). The third scheme is called Tree-Shared Multicasting (TS-MCAST) wehreby multicast traffic belonging to multiple multicast sesions can be mixed together in a burst, which is delivered via a shared multicast tree. In [1], we have evaluated several multicast schemes with static sessions at the flow level. In this paper, we perform a simple analysis for the multicast schemes and evaluate the performance of three multicast schemes, focusing on the case with dynamic sessions in terms of the link utilization, bandwidth consumption, blocking (loss) probability, goodput and the processing loads.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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paper_title: Evaluation of multicast schemes in optical burst-switched networks: the case with dynamic sessions

paper_content:

In this paper, we evaluate the performance of several multicast schemes in optical burst-switched WDM networks taking into accounts the overheads due to control packets and guard bands (Gbs) of bursts on separate channels (wavelengths). A straightforward scheme is called Separate Multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to Gbs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called Multiple Unicasting (M-UCAST). The third scheme is called Tree-Shared Multicasting (TS-MCAST) wehreby multicast traffic belonging to multiple multicast sesions can be mixed together in a burst, which is delivered via a shared multicast tree. In [1], we have evaluated several multicast schemes with static sessions at the flow level. In this paper, we perform a simple analysis for the multicast schemes and evaluate the performance of three multicast schemes, focusing on the case with dynamic sessions in terms of the link utilization, bandwidth consumption, blocking (loss) probability, goodput and the processing loads.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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paper_title: Evaluation of multicast schemes in optical burst-switched networks: the case with dynamic sessions

paper_content:

In this paper, we evaluate the performance of several multicast schemes in optical burst-switched WDM networks taking into accounts the overheads due to control packets and guard bands (Gbs) of bursts on separate channels (wavelengths). A straightforward scheme is called Separate Multicasting (S-MCAST) where each source node constructs separate bursts for its multicast (per each multicast session) and unicast traffic. To reduce the overhead due to Gbs (and control packets), one may piggyback the multicast traffic in bursts containing unicast traffic using a scheme called Multiple Unicasting (M-UCAST). The third scheme is called Tree-Shared Multicasting (TS-MCAST) wehreby multicast traffic belonging to multiple multicast sesions can be mixed together in a burst, which is delivered via a shared multicast tree. In [1], we have evaluated several multicast schemes with static sessions at the flow level. In this paper, we perform a simple analysis for the multicast schemes and evaluate the performance of three multicast schemes, focusing on the case with dynamic sessions in terms of the link utilization, bandwidth consumption, blocking (loss) probability, goodput and the processing loads.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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Title: A Survey of Multicasting in Optical Burst Switched Networks: Future Research Directions

Section 1: INTRODUCTION
Description 1: Summarize the introduction to Optical Burst Switching (OBS) technology, its benefits, and the relevance of multicast services over OBS networks.

Section 2: Optical Burst Switched Networks
Description 2: Discuss the characteristics and operational principles of Optical Burst Switched Networks, including the burstification process, control packet creation, and the separation of control functions and data transmission.

Section 3: Multicasting in Optical Burst Switched Networks
Description 3: Provide an overview of multicasting in OBS networks, outlining the increasing demand for multimedia distribution, multicast tree construction, control packet transmission, and guard band considerations.

Section 4: MULTICASTING SCHEMES IN OPTICAL BURST SWITCHED NETWORKS
Description 4: Detail the various multicasting schemes in OBS, including Separate Multicasting (S-MCAST), Multiple Unicasting (M-UCAST), and Tree Shared Multicasting (TS-MCAST), and evaluate their performance.

Section 5: TREE SHARING MULTICASTING
Description 5: Explain the concept of tree sharing in multicasting, including different strategies for tree sharing and the construction of shared trees using algorithms like Greedy, Breadth First Search, and Member Initiated.

Section 6: MULTICAST SCHEMES FOR DYNAMIC SESSIONS AND MEMBERSHIP
Description 6: Discuss the extension of multicast schemes to support dynamic sessions and membership changes, including approaches for dynamic sessions and re-grooming strategies for dynamic membership.

Section 7: Small Group Multicast with Deflection Routing
Description 7: Describe the OXCast multicast scheme for small group multicasting in OBS, including its approach to deflection routing and its impact on burst loss probability and delay.

Section 8: CONCLUSION AND FUTURE RESEARCH DIRECTIONS
Description 8: Summarize the key findings and identify the serious problems and areas that require further research, such as QoS-aware multicast sessions, optimal resource utilization, and the impact on business models.