• ETRI Journal
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• v.33 no.3
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• pp.355-365
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• 2011

IPTV broadcast channels and video content distribution are increasingly saturating network paths. New solutions based on inter-domain multicast protocols could contribute to the enhancement of multimedia content distribution over the Internet. The aim of this paper is to propose new capabilities for an existing inter-domain multicast protocol, the Protocol Independent Multicast-Sparse Mode. We describe the modified protocol and analyze its behavior using newly developed tools based on an open-source software simulator. The resulting protocol does not require topology information, which is advantageous for easier deployment. In addition, the adopted solution avoids inherent problems with inter-domain multicast routing, such as multiple paths and path asymmetries.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.27-36
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• 2010

In wireless networks environment, there are attempts for constructing systems through which we can monitor and control various electronic devices used in large buildings at remoteness by using Zigbee protocol. Since address assignment method of DAA in Zigbee has a depth restriction, we cannot construct a network in large buildings. And also communication failures are frequent in a large network since broadcast storm can be occurred due to frequent broadcasts among a lot of nodes at AODV routing used in Zigbee. In order to solve these problems, in this paper, we propose a novel protocol which has improved the restriction of depth by using a fixed address assignment method, and has enhanced the broadcast occurrence by devising a static routing method to a packet movement between floors. Regardless of entire network, additionally, this was to enable internal communication reliably by composing an independent PAN. Specially, in this paper, we implemented the proposed wireless protocol and proved stability and practicality through experiment appliances of control of devices established in a large building.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.12C
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• pp.208-217
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• 2001

In mobile Internet environment, providing multicast requires much more complex mechanism comparing with the unicast Mobile IP routing protocol. This is because multicast datagrams are sent to a group address that do not belong to a specific network. The IETF Mobile IP suggested two approaches for mobile multicasting, namely remote subscription and hi-directional tunneling. In remote subscription, a mobile node may join a group via a local multicast router on the visited subnet. Therefore remote subscription may cause much datagram loss while reconstructing the delivery tee. In bi-directional tunneling, a mobile node may join a group via a hi-directional tunnel to its home agent. Bi-directional tunneling may suffer from inefficient routing. In this paper, we proposed a new mobile multicasting protocol, Mobile If Multicast using Local Broadcast(MIMLB) which can receive multicast datagrams as fast as possible and optimize routing path for multicast delivery. The MIMLB protocol uses hi-directional tunneling to receive multicast datagrams. And the MIMLB protocol can resolve datagram duplicated problem and optimize routing path by using local broadcast. Simulation results show that MIMLB reduces delivery path length and optimizes multicast routing path when a mobile nod? moves into a foreign network.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.3
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• pp.125-133
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• 2002

In this paper, we present an efficient broadcast protocol, called Btoken, that ensures total ordering of messages and atomicity of delivery in the large scaled distributed systems. Unlike the existing token-passing based protocol, Btoken does not circulate a token around the ring, instead, it uses three kinds of control messages for token transmission. The token has a sequence number field for broadcasting message, and the only site having the token can broadcast a message. When a site wishes to broadcast, It must send a message to the token site requesting the token. The token site sends a message with the token to the requester When the requester receives the token, it becomes the current token site and broadcasts a new message after setting sequence number derived from a field of the token into its message. Upon reception of it, any operating member is informed the position of the token site and will send token requesting message to the new token site. However, the other site may request the token to the old token site prior to receiving the broadcast message from the new token site. To resolve this problem, Btoken uses a message which is sent to the current token site by the old token site notifying who is the next token requester. Results of our simulation of the protocol show that Btoken is more efficient in the large scaled distributed system compared to existing broadcast protocols.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.12
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• pp.3257-3274
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• 2012

Broadcast routing has become an important research field for vehicular ad-hoc networks (VANETs) recently. However, the packet delivery rate is generally low in existing VANET broadcast routing protocols. Therefore, the design of an appropriate broadcast protocol based on the features of VANET has become a crucial part of the development of VANET. This paper analyzes the disadvantage of existing broadcast routing protocols in VANETs, and proposes an improved algorithm (namely ODAM-C) based on the ODAM (Optimized Dissemination of Alarm Messages) protocol. The ODAM-C algorithm improves the packet delivery rate by two mechanisms based on the forwarding features of ODAM. The first distance-based mechanism reduces the possibility of packet loss by considering the angles between source nodes, forwarding nodes and receiving nodes. The second mechanism increases the redundancy of forwarding nodes to guarantee the packet success delivery ratio. We show by analysis and simulations that the proposed algorithm can improve packet delivery rate for vehicular networks compared against two widely-used existing protocols.

• Journal of Korea Society of Digital Industry and Information Management
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• v.18 no.2
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• pp.1-8
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• 2022

The message propagation between vehicles must be efficiently performed to quickly transmit information between vehicles in vehicle ad hoc networks (VANETs). Broadcasting can be the most effective solution for propagating these messages. However, broadcasting can cause broadcast storm problems, which can reduce the performance of the overall network. Therefore, rapid information delivery in VANET requires a method that can propagate messages quickly without causing the broadcast storm problems. This paper proposes a lightweight and opportunistic broadcast (LOB) protocol that leverages the features of opportunistic routing to propagate messages quickly while minimizing the load on the network in VANETs where the network topology changes frequently. LOB does not require any routing information like greedy forwarding scheme, and neighboring nodes at the farthest distance within the range of transmission nodes are likely to be selected as forwarding nodes, and multiple forwarding candidate nodes like opportunistic routing scheme can increase packet transmission rates. Simulation results using ns-2 showed that LOB outperformed existing broadcast protocols in terms of packet rate and packet delay.

• Proceedings of the Korean Information Science Society Conference
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• 2008.06d
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• pp.291-296
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• 2008

Wireless network technologies are becoming more widely used in industrial environment. The industrial communication system requires a real-time delivery of messages. The sensors periodically senses the physical environment and wants to deliver the data in real-time to the sink. This paper proposes a real-time protocol for periodic messages on wireless sensor and actor networks to be used in industrial communications. The proposed protocol delivers the data message using the shortest path from the source and the nearest actor. The protocol considers the energy consumption by reducing the number of broadcast messages during flooding. We have evaluated the performance of the proposed protocol using QualNet simulator. The simulation results show that the data messages have been delivered in real-time and the number of broadcast messages is reduced from 90% to 35% compared the existing protocols.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.2
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• pp.81-85
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• 2009

In VANET, it is required one-way broadcast transmission because vehicles move at high speed and warning messages need to broadcast. our protocol employs digital signatures to authenticate nodes along the path. this prevents impersonation attacks and message modification attacks. our protocol also employs the node list to recognize intermediate nodes of the path. The node list, the time, and the nonce can prevent replay attacks.

• Journal of the Korean Data and Information Science Society
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• v.21 no.4
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• pp.783-793
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• 2010

Several multi-hop applications developed for vehicular ad hoc networks use broadcast as a means to either discover nearby neighbors or propagate useful traffic information to other vehicles located within a certain geographical area. However, the conventional broadcast mechanism may lead to the so-called broadcast storm problem, a scenario in which there is a high level of contention and collisions at the link layer due to an excessive number of broadcast packets. We present a fuzzy alert message dissemination algorithm to improve performance for road safety alert application in Vehicular Ad-hoc Network (VANET). In the proposed algorithm, when a vehicle receives an alert message for the first time, the vehicle rebroadcasts the alert message according to the fuzzy control rules for rebroadcast degree, where the rebroadcast degree depends on the current traffic density of the road and the distance between source vehicle and destination vehicle. Also, the proposed algorithm is the hybrid algorithm that uses broadcast protocol together with token protocol according to traffic density. The performance of the proposed algorithm is evaluated through simulation and compared with that of other alert message dissemination algorithms.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.2
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• pp.77-85
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• 2015

This paper presents our performance evaluation after the way of minimizing waiting times between channel switching for eMBMS(evolved Multimedia Broadcast/Multicast Services) technique in LTE-Advanced systems. Existing composition of MBMS using IGMP(Internet Group Management Protocol) transfers the data with Multicast from BM-SC(Broadcast Multicast Service Center) to eNB(evolevd Node B) and with Broadcast from eNB to UE(User Equipment). Therefore, in case of channel switching, IGMP Join report should be transferred to BM-SC and then wait user's contents to be retransferred from eNB. To achieve this, Subscriber Channel technique of priorities is used for minimizing waiting times between channel switching as UE broadcasts favorite channels in advance.