Apparatus for providing cryptographic support in a network

Abstract

A host interface comprising a reassembler for reassembling and decrypting data that has been encrypted in accordance with a pre-defined key and segmented into a plurality of asynchronous transfer mode (ATM) cells. Each cell comprises a virtual channel identifier (VCI), a multiplexing identifier (MID) if the data is transmitted using the CCITT specified Class 4 connectionless transfer ATM adaptation layer (AAL), and a cell body. The reassembler comprises a cell manager for separating each cell body from that cell body's corresponding VCI and MID (if present), a linked list manager for managing and storing linked list data indicative of addresses at which the cell bodies are to be stored, a content addressable memory (CAM) for managing and storing the VCIs (and MIDs for connectionless data) and providing pointers into the linked list data, a lookup controller for writing the VCIs to the CAM, a reassembly buffer for storing the cell bodies, and a decryption device for decrypting the data and writing the decrypted data to the reassembly buffer. The major subsections operate concurrently to form an ATM cell-processing pipeline. The interface may also comprise a segmenter for encrypting data received from a host computer and segmenting the encrypted data into a plurality of ATM cells.