Abstract: A wireless cellular network includes an access point selector that selects an access point for forwarding data from a wireless device. When data is received with an unacceptable quality level, the access point selector queries other access points for the same data. The queried access points send data quality information to the access point selector. The access point selector uses the data quality information for selecting another one of the access points to forward data from the wireless device.
Type:
Grant
Filed:
December 5, 2002
Date of Patent:
October 7, 2008
Assignee:
Cisco Technology, Inc.
Inventors:
Ramanathan Jagadeesan, Bich Nguyen, Kent G. Iverson
Abstract: A master Timestamp Synchronization Circuit (TSC) in a Cable Modem Termination System (CMTS) estimates a master timestamp value for an upcoming time reference. The master TSC sends the master timestamp value asynchronously over an Internet Protocol (IP) network to slave TSCs in other CMTSs. The slave TSC compares a local timestamp value with the master timestamp value when the upcoming time reference occurs. If the local timestamp value does not match the master timestamp value, the slave TSC is resynchronized using the master timestamp value.