Method and mobile node for packet transmission in mobile internet protocol network

A mobile terminal apparatus for packet transmission, comprising:

• a first module configured to send a first Firewall Detection (FD) packet encapsulated with IP security (IPsec) protocol and a second FD packet encapsulated with IPsec protocol and User Datagram Payload (UDP) protocol to a Home Agent (HA);
• a second module configured to determine whether there is a firewall blocking an IPsec packet by way of determining whether a Firewall Detection Reply (FDR) packet received from the HA corresponds to the first FD packet encapsulated with the IPsec protocol or the second FD packet encapsulated with the IPsec protocol and the UDP protocol,
• wherein the second module comprises:
• a sub-module configured to determine that there is no firewall blocking the IPsec packet when determining that the FDR packet received corresponds to the first FD packet;
• and a sub-module configured to determine that there is the firewall blocking the IPsec packet when determining that the FDR packet received corresponds to the second FD packet;
• a third module configured to encapsulate packets with the UDP protocol and perform binding update and packet exchange when the second module determines that there is the firewall blocking the IPsec packet;
• and
• a fourth module configured to perform binding update and packet exchange when the second module determines that there is no firewall blocking the IPsec packet.

A Mobile Internet Protocol (MIP) system, the system comprising at least one mobile terminal apparatus configured to:

• send a first Firewall Detection (FD) packet encapsulated with IP security (IPsec) protocol and a second FD packet encapsulated with IPsec protocol and User Datagram Payload (UDP) protocol to a Home Agent (HA);
• determine whether there is a firewall blocking an IPsec packet by way of determining whether a Firewall Detection Reply (FDR) packet received from the HA corresponds to the first FD packet encapsulated with the IPsec protocol or the second FD packet encapsulated with the IPsec protocol and the UDP protocol;
• and determining that there is no firewall blocking the IPsec packet when the FDR packet received corresponds to the first FD packet;
• and determining that there is the firewall blocking the IPsec packet when the FDR packet received corresponds to the second FD packet;
• encapsulate packets with the UDP protocol and performing binding update and packet exchange when there is the firewall blocking the IPsec packet;
• and
• perform binding update and packet exchange when there is no firewall blocking the IPsec packet.