The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 28, 2002
Filed:
Sep. 28, 1998
Prasasth R. Palnati, Waltham, MA (US);
Ascend Communications, Inc., Westford, MA (US);
Abstract
Port cards in an ATM switch store parameters for virtual channel connections (VCCs) and virtual path connections (VPCs) in separate areas of a virtual connection parameter table (VCPT), the areas being defined by a VCC pointer and a VPC pointer. Also, a number of “free lists” are used to identify unused single locations (for VPCs) or chunks of locations (for sets of VCCs) that are available for re-allocation. Different free lists are used for different-sized sets of VCCs, i.e., sets configured to use different maximum numbers of VCI bits. When a new VPC is created, a VCPT location identified by an entry in the VPC free list is allocated, if such an entry exists. Otherwise a VCPT location is allocated by advancing the VPC pointer. De-allocation of a VPC entry proceeds in reverse order, i.e., the VPC area is shrunk by backing up the VPC pointer if possible, and if not the de-allocated entry is placed on the VPC free list. Similar allocation and de-allocation processes are used for newly-created VCCs, using the VCC free list appropriate based on the maximum number of VCCs that may be in the set of VCCs. A consolidation technique further backs up the VCC pointer when possible to maximize space available for allocation, and also combines entries from the free lists to create larger-sized chunks. Such combined chunks may be allocated in whole or split into smaller chunks as needed for subsequent allocations.