Roaming IP address management method, network surfing method, source tracing method, device and system

The invention discloses a roaming IP address management method, a network surfing method, a source tracing method, a device and a system. After an identity position register detects that a mobile user which does not belong to the network roams to the network, a static state public network IP address is distributed to the mobile user. When accessing the Internet, the roaming mobile user uses the static state public network IP address. During source tracing, the static state public network IP address used by the mobile user during the Internet accessing in the roaming period is acquired, then the identity position register to which the static state public network IP belongs is further searched, and then the identify position register finds out a mobile user corresponding to the static state public network IP address for records of the static state public network IP address for each mobile user. According to the invention, when the mobile user is roaming, the static state public network IP address can be distributed for the roaming place; the mobile user uses the same IP address during the roaming; and during source tracing, the corresponding user information can be acquired only by inquiring the IP on the identity position register, so simple, quick and precise source tracing is achieved.