Patent ID: 6473432
Filing Date: 2002-10-29
Classification: H04L,H04Q

Abstract:
A buffer control apparatus for controlling storage process for a common buffer, which is commonly used for a plurality of channels and temporarily stores data received from said channels,said buffer control apparatus comprising: a route discriminating section for identifying the individual channels of said received data based on a channel identifier stored in said received data; a storage section for storing at least information concerning a stored position of said received data within said common buffer of said received data within said common buffer for the individual channels; and a control section for performing a control operation for storing received data into said common buffer and managing the stored position of said received data in said common buffer for the individual channels based on a result of channel identification in said route discriminating section and said information concerning the stored position in said storage section: wherein said storage section comprises: a link memory for storing, for each route, a series of address information of said received data within said common buffer as being successively linked in an order of said received data, a per-route information memory for storing, for each route, the address information of the received data initially stored in said common buffer, the address information of the received data lastly stored in said common buffer, and an amount of the received data, and an empty address information memory for storing empty address information within said common buffer; and wherein, according to the result of route identification in said route discriminating section and the empty address information in said empty address information memory, said control section causes the received data to be stored at a predetermined empty address in said common buffer and, based on said empty address, updates each of the linking state in said link memory, the address information and the amount of received data in said per-route information memory, and the empty address information in said empty address information memory; a threshold storing section for storing a threshold value concerning a congested state in said common buffer; wherein said control section comprises: a congested state detecting section for detecting said congested state of said common buffer according to said threshold value of said threshold storing section, and a storage processing restricting section which can restrain, for each route, said received data from being stored into said common buffer when said congested state detecting section detects said contested state; wherein said threshold storing section comprises a total data amount threshold storing section for storing a total data amount threshold value concerning a total data amount within said common buffer, and a minimally-guaranteed threshold storing section for storing a minimally-guaranteed threshold value for an amount of data to be minimally guaranteed for each route within said common buffer; wherein said congested state detecting section comprises a total data mount evaluating section for judging whether the total data amount within said common buffer exceeds said total data threshold value or not, said congested state detecting section being configured so as to detect said congested state when said total data amount evaluating section judges the total data amount within said common buffer to be higher than said total data amount threshold value; and wherein said storage processing restricting section comprises a per-route data amount evaluating section for judging, when said congested state detecting section detects said congested state, whether or not there exists within said common buffer a route whose per-route data amount exceeds said minimally guaranteed threshold value, said storage processing restricting section being configured to restrain, when said per-route data amount evaluating section judges that there is a route exceeding said minimally guaranteed threshold value, new received data from being stored into said common buffer for said route; wherein said storage processing restricting section is configured such that, even when said congested state detecting section detects a congested state whereby new received data are restrained from being stored into said common buffer for a certain route, dependent data which form a single data together with the received data already stored in said common buffer for the are all owed to be stored into said common buffer.