Shin Gak Kang

Multicast delivery based on unicast and subnet multicast

In spite of the numerous works previously made, IP multicasting has not been widely deployed in the public Internet. We present a realistic alternative scheme for IP multicasting, which is based on the unicast transport from a remote sender to a local subnet and the multicast forwarding to receivers within the subnet.

A Survey on Peer-to-Peer Overlay Network Schemes

With the growing popularity of multimedia services such as IPTV, these P2P network overlay schemes are in the limelight and actively under studied as a good alternative or complementary solution for internet multimedia service systems. Therefore, in this paper, we review and compare the P2P overlay network schemes that have been introduced and researched recently by categorizing into two groups, i.e., structured and unstructured.

Labeling System for Countering SIP spam

In this paper, SIP spam labeling system is proposed to detect, block or filter IP multimedia application spam over SIP network appropriately according to spam management policy of the spam recipient. In the SIP spam labeling system, a SIP message is labeled with the insertion of an agreed text meaning that the attempted session is for spam, and the label is used to identify IP application spam. The architecture of SIP spam labeling system, functions of each component, and spam detection and filtering process in SIP labeling system are described in the body.

Enhancement of the CBT multicast routing protocol

We propose a simple practical scheme for many-to-many IP multicasting. The proposed scheme is based on the core based tree (CBT) protocol, and designed to enhance the CBT in the viewpoints of tree cost and traffic concentration. In the scheme, each group user is simply connected to the nearest core router in the network. Each core router forwards the source traffic to networks via the pre-configured backbone core trees spanning all the core routers in the network. To ensure that the backbone core tree keeps only the core routers with active group users, the core routers that have no downstream users are removed from backbone core tree. By experiments, we see that the proposed scheme significantly improves the existing CBT scheme in terms of tree cost and traffic concentration.

QoS architecture for NGN

NGN (next generation network) architecture is assumed as a next generation network where wired and wireless services are converged and quality of service is guaranteed. Though there have been several works on QoS provisioning mechanisms to improve quality of service in the current Internet, such as RSVP, DiffServ, because of the complexity and scalability issues these mechanisms have not been deployed yet. In this paper, we propose a QoS mechanism to enhance end-to-end QoS though it is very simple but reasonable. The proposed mechanism uses controlling signal to reserve network resources from sending network to receiving network similarly to RSVP, then send data with QoS enabled flag similarly to DiffServ. In this paper we illustrate the proposed resource reservation mechanism with network topology and signaling

PIM Multicast Spam Countering Method Using Blacklist in Rendezvous Point

Spam has been an annoying problem especially to Internet e-mail system nowadays. Many solutions have been deployed, but none have actually solved this problem. Various new applications based on the Internet are emerging very fast, and many of those applications are quickly being a good target for spammers. IP multicast provides flexibility in communication pattern with capability of sending same messages to multiple users. It can be used in various services like IPTV or conference communication. Since, multiple users can receive same message simultaneously, IP multicast is a great target for IP spammers. This paper propose spam countering method in IP multicast environment using PIM multicast protocol. If the multicast service receiver suspects that the receiving multicast traffic is a spam, it would report to the PIM rendezvous point. The PIM rendezvous point will manage multicast flow according to the spam reports received from the receivers. This paper made detailed description of the spam countering method that can be used to prevent spam in PIM-based IP multicast services.

ARQ scheme of multimedia streaming for hybrid delivery over heterogeneous network

Nowadays, many mobile devices have multiple networking modules to receive data from various networks such as WI-FI, 3G, Wimax, DVB-H, etc. The mobile devices are used to receive multimedia streams through various networking interfaces. However, mobile characteristics can cause loss of packets and needs an effective method to recover the loss to provide high-quality multimedia streaming service. ARQ (Automatic Repeat Query) can be used to re-receive the loss packets that are being delivered. The heterogeneous networks can be used to effectively deliver multimedia stream and also provides ARQ to recover the loss packets. The retransmitted data can be delivered over bi-directional network such as Internet. This paper proposes a hybrid delivery for heterogeneous network environment and efficient ARQ that can be considered for multimedia streaming.

Relayed multicast protocol for 1-to-many group communications

IP multicast shows very strong advantage in the group communication services. But to deploy IP multicast in the current Internet, every IP routers must be changed into multicast enabled ones and several deployment issues should be solved. So theses problems prevent IP multicast mechanism from being deployed in IP world. And these problems give a good reason why todays group communication uses replicated IP unicast mechanism instead of IP multicast. Recently an overlay multicast is proposed as an alternative method of IP multicast. We propose a framework as an application-layer way to provide end-to-end multicast services over IP-network environment. In this paper we define the basic concepts of relayed multicast scheme, data delivery models, service scenarios and some test issues of RMCP as well as implementation and test on APAN

A framework for internet group communications services

IP multicast shows a very strong advantage in the group communication services. To deploy IP multicast in the current Internet, every IP router must be changed into multicast enabled ones and several deployment issues should be solved. These problems prevent IP multicast mechanism from being deployed in the IP world. These problems gives a good reason why todays group communication uses replicated IP unicast mechanism instead of IP multicast. Recently an overlay multicast is proposed as an alternative method of IP multicast. We propose a RMCP (relayed multicast protocol) as an application-layer protocol for providing end-to-end multicast services over IP-network environment. We also push RMCP into ITU-T and ISO standardization activity. In this paper we define the basic concepts of relayed multicast scheme, data delivery models, service scenarios and standardization activities on RMCP