Browse Prior Art Database

Method for efficient multiple CID lookup for AAL2

IP.com Disclosure Number: IPCOM000009981D
Publication Date: 2002-Oct-02
Document File: 3 page(s) / 157K

Publishing Venue

The IP.com Prior Art Database

Abstract

Disclosed is a method for efficient multiple channel identification (CID) lookup for asynchronous transfer mode adaptation layer 2 (AAL2). Benefits include improved performance.

This text was extracted from a Microsoft Word document.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 69% of the total text.

Method for efficient multiple CID lookup for AAL2

Disclosed is a method for efficient multiple channel identification (CID) lookup for asynchronous transfer mode adaptation layer 2 (AAL2). Benefits include improved performance.

Background

        � � � � � The following terms are used in conjunction with the disclosed method:

Term        � � � � � � � � � � � � � Description

AAL2        � � � � � � � � � � � � ATM adaptation layer 2

ATM        � � � � � � � � � � � � � Asynchronous transfer mode

CID        � � � � � � � � � � � � � � � Channel identification

CPS-PH        � � � � � � � � Common part sublayer – packet header

CPS-PP        � � � � � � � � Common part sublayer – packet payload

VPI        � � � � � � � � � � � � � � � Virtual path identifier

VCI        � � � � � � � � � � � � � � � Virtual channel identifier

Description

        � � � � � The disclosed method improves look-up time when more than one CID exists in an AAL2 cell. In an AAL2 lookup at CID level, the fields required to perform a lookup are VPI, VCI, and CID). Each CPS packet contains one CID. Because all the CIDs in the same AAL2 cell have the same VPI/VCI, a lookup is performed using the common part, which consists of VPI and VCI. This common lookup returns a pointer, designated as Pointer A, which points to a location allocated with 256 units to store CID-specific information (see Figure 1). Each unit location stores information for each CID. Allowable values for a CID are 8 to 255.

        � � � � � The CID is used as an offset with Pointer A as a base to point to informat...