Proxy Mobile IPv6
The existing MN based mobility support mechanism requires additional stacks and signaling for the MN. This could bring overhead such as battery power and computation resource consumption. Network based mobility support mechanism is another approach to solve the problems and support the IP mobility. This is a kind of extended version of Mobile IPv6 [10] and Hierarchal Mobile IPv6 [11]. In the network based mobility support mechanism, MN does not need to install additional stacks and exchange signals. A special mobility agent in the network performs the signaling and does the mobility management on behalf of the MN. The IETF NETLMM working Group has researching under proxy mobile IPv6. There are two main components for the proxy mobile IPv6, a Local Mobility Anchor (LMA) and a Mobile Access Gateway (MAG). The LMA performs home agent roles, as defined in Mobile IPv6 base specification [1], for the MN in the Proxy mobile IPv6 domain. LMA is the topological anchor point for the MN’s home network prefix (HNP) and it maintains MN’s binding state. The MAG performs mobility related signaling to the LMA for the MN and tracks the MN’s movements.
Figure [2] presents the operation and message flow of the PMIPv6 [12]. The PMIPv6 protocol operation consists of four phases. In the first phase, MAG retrieves the MN’s profile using its current identifier. The Binding Update (BU) is the second phase, in which the MAG will send a Proxy BU request to the LMA in order to register the current point of attachment of the MN. Accordingly, a binding cache entry and a tunnel for the MN’s home prefix will be created. The third phase will be the MAG emulating the mobile node’s home interface on the access interface. Therefore, the MN will always believe it is in the home network. Fourthly, the LMA reply Proxy Bind Acknowledge (PBA) message with the MN’s HNP. After receiving the Router Advertise (RA) message, the MN creates its IP address. For packet routing, the LMA will route all received packets over the established tunnel to the MAG. The MAG forwards these packets to the MN. Certainly, the MAG will relay all the received packets over the tunnel to the LMA and then they will be routed towards the CN.
The existing MN based mobility support mechanism requires additional stacks and signaling for the MN. This could bring overhead such as battery power and computation resource consumption. Network based mobility support mechanism is another approach to solve the problems and support the IP mobility. This is a kind of extended version of Mobile IPv6 [10] and Hierarchal Mobile IPv6 [11]. In the network based mobility support mechanism, MN does not need to install additional stacks and exchange signals. A special mobility agent in the network performs the signaling and does the mobility management on behalf of the MN. The IETF NETLMM working Group has researching under proxy mobile IPv6. There are two main components for the proxy mobile IPv6, a Local Mobility Anchor (LMA) and a Mobile Access Gateway (MAG). The LMA performs home agent roles, as defined in Mobile IPv6 base specification [1], for the MN in the Proxy mobile IPv6 domain. LMA is the topological anchor point for the MN’s home network prefix (HNP) and it maintains MN’s binding state. The MAG performs mobility related signaling to the LMA for the MN and tracks the MN’s movements.
Figure [2] presents the operation and message flow of the PMIPv6 [12]. The PMIPv6 protocol operation consists of four phases. In the first phase, MAG retrieves the MN’s profile using its current identifier. The Binding Update (BU) is the second phase, in which the MAG will send a Proxy BU request to the LMA in order to register the current point of attachment of the MN. Accordingly, a binding cache entry and a tunnel for the MN’s home prefix will be created. The third phase will be the MAG emulating the mobile node’s home interface on the access interface. Therefore, the MN will always believe it is in the home network. Fourthly, the LMA reply Proxy Bind Acknowledge (PBA) message with the MN’s HNP. After receiving the Router Advertise (RA) message, the MN creates its IP address. For packet routing, the LMA will route all received packets over the established tunnel to the MAG. The MAG forwards these packets to the MN. Certainly, the MAG will relay all the received packets over the tunnel to the LMA and then they will be routed towards the CN.