Abstract: In a handoff system and method for a dual mode terminal, the handoff system includes: a dual mode terminal which receives a message containing location information of a router of a second network while performing handoff from a first network to the second network, and which transmits a registration request message containing the location information of the router; and a home agent which transcodes data transmitted from a content providing server to be adapted for a bandwidth of the second network on the basis of information contained in the registration request message received from the dual mode terminal, and which transmits the transcoded data to the dual mode terminal.

Abstract: A method for scaling a display size between different types of user agents. The method includes exchanging session initiation protocol messages including media information when performing a call setup for setting up a media session between the user agents; determining any one of the user agents to scale the display size from the exchanged media information; and scaling, by the determined user agent, the display size on the basis of the media information, and sending video data subject to the scaling to the other user agent(s).

Abstract: A packet processing terminal and method for compressing a header of a packet. When it is determined an IP header is to be compressed in order that a terminal removes overhead of a generated packet, an IP header compression option is added to a socket option of a socket generated in order to exchange the packet between an application module and an OS module. And, when the application module sets the IP header compression option, the IP header of the packet is compressed by the OS module using a compression method corresponding to option information of the set IP header compression option.

Abstract: In a handoff system and method for a dual mode terminal, the handoff system includes: a dual mode terminal which receives a message containing location information of a router of a second network while performing handoff from a first network to the second network, and which transmits a registration request message containing the location information of the router; and a home agent which transcodes data transmitted from a content providing server to be adapted for a bandwidth of the second network on the basis of information contained in the registration request message received from the dual mode terminal, and which transmits the transcoded data to the dual mode terminal.

Abstract: A method for scaling a display size between different types of user agents. The method includes exchanging session initiation protocol messages including media information when performing a call setup for setting up a media session between the user agents; determining any one of the user agents to scale the display size from the exchanged media information; and scaling, by the determined user agent, the display size on the basis of the media information, and sending video data subject to the scaling to the other user agent(s).

Abstract: A packet processing terminal and method for compressing a header of a packet. When it is determined an IP header is to be compressed in order that a terminal removes overhead of a generated packet, an IP header compression option is added to a socket option of a socket generated in order to exchange the packet between an application module and an OS module. And, when the application module sets the IP header compression option, the IP header of the packet is compressed by the OS module using a compression method corresponding to option information of the set IP header compression option.