Profile-based mobile MPLS protocol

Abstract

Mobile MPLS is a new scheme that integrates mobile IP and MPLS protocols, in order to enable the MPLS protocol to support mobility. In mobile MPLS, when a correspondent node (CN) wants to communicate with a mobile user, the CN will first send its packets to the mobile user's home domain. Then, the home agent (HA) of the mobile user will forward the packets to the mobile user through the label switched path (LSP) from the HA to the current location of the mobile user. This forwarding process leads to a "triangle routing" problem. Even if route optimization is applied, several of the packets transmitted at the beginning of the connection will still be forwarded through the remote HA of the mobile user, since there is no address binding for the mobile user in the cache of the CN at the very beginning of the transmission. However, if the mobile user's behavior, e.g. the user's mobility pattern, travel schedule, are predictable or well-known before the transmission of the packets, this kind of "triangle routing" problem can be avoided. We propose a profile-based mobile MPLS protocol. The profiles maintain the regular behaviors of the mobile users. If the CN is able to obtain the profile of the mobile user, it will know (to some extend of accuracy) the current location of the mobile user and forward its traffic to the area the user is expected to be, thus eliminating the "triangle routing". Two schemes are proposed to maintain the profiles of the mobile users. One is based on a distributed, the second on a centralized approach. In the distributed scheme, the profiles are obtained directly from the mobile users, while in the centralized scheme a profile server is applied to maintain the profiles of all the mobile users in a domain. With the profile-based mobile MPLS approach, the delay for the traffic to the mobile user is reduced and the network performance is enhanced.