Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
115 words
Apparatus comprising a memory (380) having a plurality of memory locations for the storage of data words contained in respective data packets, said data packets being associated with respective levels of priority (CS), said levels of priority being associated with respective priorly stored memory threshold values (310,315,320,325), CHARACTERIZED BY means (350,340) operative when one of said packets is being stored in said memory for determining the number of data words currently stored in said memory and for effectively blocking the storage of the data words contained in said one data packet if the value of said number exceeds the value of the memory threshold associated with the respective priority level of said one data packet.
Claim 2
Dependent Claim
115 words
Apparatus comprising a memory (380) having a plurality of memory locations for the storage of data words contained in respective data packets, said data packets being associated with respective levels of priority (CS), said levels of priority being associated with respective priorly stored memory threshold values (310,315,320,325), CHARACTERIZED BY means (350,340) operative when one of said packets is being stored in said memory for determining the number of data words currently stored in said memory and for effectively blocking the storage of the data words contained in said one data packet if the value of said number exceeds the value of the memory threshold associated with the respective priority level of said one data packet.
Claim 3
Dependent Claim
51 words
Apparatus as claimed in claim 1 wherein said means for determining includes means for allowing said later words contained in said one data packet to be stored in said memory if the value of said number is less than the value of the memory threshold associated with said one data packet.
Claim 4
Dependent Claim
76 words
Apparatus as claimed in claim 1 or claim 2 further comprising memory write (360) and read (370) pointer registers, said write pointer register containing the address of the memory location at which said one data word is to be stored and said read pointer register containing the address of the next memory location which is to be read, and wherein said number is determined as function of the contents of said read and write pointer registers.
Claim 5
Dependent Claim
81 words
Apparatus as claimed in any of the preceding claims wherein said apparatus is a packet switch arranged to receive packets of said data words from an external source of data packets, wherein each of said data packets includes a respective class-of-service mark identifying a respective one of said memory threshold values, and wherein the memory threshold value that is associated with said one data word is derived from the class-of-service mark contained in the data packet associated said one data word.
Claim 6
Dependent Claim
66 words
Apparatus set as claimed in any of the preceding claims wherein each of said threshold values is programmable and wherein said apparatus includes means (7,8) for changing the value of at least one of said threshold values responsive to receipt from a user of said apparatus of an instruction to do so, in which said instruction contains the new value of said at least one threshold.