| 摘要 |
<p>A mobile user terminal (402) accesses a packet data network (450) through one or more of several network access points (404-412). One or more control points (432-440) determines which network access point or points the user terminal is to access. Control may be retained in the current control point, or transferred to another control point, whenever it is convenient. There are preferably several routers, each having an associated home agent (418-420) which determines which foreign agents need to be accessed on behalf of each user terminal. There are several foreign agents (422-430), which forward packets received from a user terminal's home agent to the control point currently controlling communications with the user terminal.</p> |
