Mi Young Huh

An application level gateway for traversal of SIP transaction through NATs

SIP has been used to develop many kinds of SIP service, such as instant messaging, conference and presence, and these various services are being bundled to one application. NAT traversal has long been identified as a large problem when considered in the context of the session initiation protocol (SIP). The problem is further confused by the variety of NATs that are available in the market place today and the large number of potential deployment scenarios. In this paper, we suggest an ALG which operates inside NAT for traversal of SIP transactions

Design of disaster alerting functionality for digital signage service

It is very important sevice to provide disaster alerting function via digital signage. In this paper, we describe the design of functionality to provide disaster alert event produced from the disaster alert agency to the digital signage terminal through the digital signage server.

Study on design and implementation of audience measurement functionalities for digital signage service using Kinect camera

Digital signage service is capable of providing advertisement contents and information to users using electronic displays with network capabilities. Compared to Traditional DID (Digital Information Device) that just provides contents one-way, digital signage service can provide more advanced functionalities such as user interaction and audience measurements. By measuring audience behaviour, it is possible to provide appropriate contents to user and deduce advertisement effects. In this paper, we present implementations of audience measurement using Kinect camera since Kinect camera can track a human objects, distance calculation and gesture recognitions.

Design Considerations on Subscription and Notification Function in the Presence Services for Hierarchical ResourceList

Presence service is emerged to meet the needs of integrated service and presence service will be a core function within integrated services. IETF SIMPLE WG generates standard SIP extensions for presence service. In this paper, we described the presence service model using resource list server. We define the components to support the subscription and notification function in the presence service for hierarchical resource list. And we will describe the check points among components for interoperability reflected on the system development experience and participation experience of international interoperability test event.

Design of sip transaction distributor to support multiple applications

SIP has been used to develop many kinds of SIP service, such as instant messaging, conference and presence, and these various services are being bundled to one application. To make an application which supports various services may be not easy since the behavior of transaction user of the application is obviously become very complicated. In this paper, we describe a design of SIP transaction distributor which can support various transaction users such as VoIP, instant messaging, and presence at the same time

A study on ACK message processing mechanism in SIP transaction layer

According to the RFC3161, ACKs corresponding to 2xx responses to INVITE is handled in the transaction user as separate messages without any transactions. And the transaction user receives all retransmitted ACKs without any filtering. In this paper, ACK transactions and the finite state machines for those are defined. And the rules for matching messages to transactions are also redefined so that the retransmission of ACKs and the filtering of the retransmitted ACKs are treated in the transaction layer.