Cable data systems are used to allow cable TV subscribers to use the Hybrid-Fiber-Coax network as a communication link between their home networks and the Internet. As a result, computer information (Internet Protocol packets) can be transmitted across the Hybrid-Fiber-Coax network between home computers and the Internet. The Data Over Cable Service Interface Specification (“DOCSIS”) specifies a set of protocols used to effect a data transfer across the Hybrid-Fiber-Coax network. Two primary pieces of equipment facilitate this data transfer: cable modems (“CM”) at the subscriber's homes or offices, and a Cable Modem Termination System (“CMTS”) at the network operator's head end.
When a CM is placed into service on a network, a process of ranging and registering occurs. Communication between the CMTS and the CM initially takes place during a periodic initial maintenance window of time designated by the CMTS. The period is typically on the order of tens of milliseconds. A plurality of cable modems associated with a given CMTS media access control (“MAC”) layer device may attempt to connect during an initial maintenance window using a broadcast service identifier (“SID”). The broadcast SID is conventionally a defined 14-bit number—that may be represented in hexadecimal format—that is used by all CMs attempting to register during an initial maintenance window. This broadcast SID is typically embedded into the CMs nonvolatile memory, and is preferably a standardized number under DOCSIS.
When a connection has been established between the CMTS and a CM (or other user device for connecting with a CMTS having a MAC address), the CMTS assigns a unicast SID to be used thereafter for communications from the CM that are granted by the CMTS. As the broadcast SID is not overwritten in the CM, the assigned unicast SID is stored in memory at another location within the CM. Thus, the system of CMTS and CM is configured such that the CMTS recognizes a message from a CM that contains the universal broadcast SID and the CM's MAC address, and assigns a unicast SID for device-specific communications from the CM to the CMTS. It will be appreciated that the SIDs may also be used after initial maintenance for periodic of sporadic maintenance.
This arrangement is functional, but when there are a large number of CMs that are associated with a given MAC device at the CMTS, the time it takes for all CMs to become registered with the CMTS may take longer than a few seconds, thus making use by the CM user a less-than-optimal experience. Especially when there are a large number of devices attempting to register simultaneously, such as may occur following restoration of power after a power outage, this time lag to register can be more than just an annoyance when the traffic to be carried by the communication device is voice traffic, such as a media terminal adaptor (“MTA”) carrying voice over internet protocol (“VoIP”). The time delay could cause a call to be missed, or cause a user to decide not to place the call because of the delay. In the case of a set top box (“STB”) used in video applications, delay in registering a device may result in delay in features and service facilitated by the STB becoming available.
Thus, there is a need in the art for a method that facilitates faster registering with a CMTS of CMs, MTAs, STBs and other devices having a MAC that are attempting to join a network.
USPTO Backgrounds
USPTO Backgrounds