US 5,400,326 A · Network bridge

Abstract

A bridge for interconnecting data networks includes an adapter connected to each network and a central programmed processor. Each adapter includes a receive and a transmit FIFO storage which is less than the packets being transferred from one network to the other. The control program generates Receive Buffer Descriptors which include buffer pointers, buffer length fields and pointers to next descriptors. These Descriptors are used by the adapters to buffer received packets which are directed to another network. When a packet is buffered the control program generates Transmission Descriptors which are used by the adapter to transfer packet data to the other network. The control program modifies packet when needed by by generating and storing in its memory only the modified portion and including in the Receive Buffer Descriptor pointers which the buffered information which is to be transmitted and the sequence.

Claims6

Dependent claims

A bridge for receiving data packets from a first communication network and transmitting them on to a second communication network comprising:

a first adapter connected to the first network for receiving, storing and examining at least a portion of a received packet to determine if the packet is to be transferred to the second network;
a processor including a control program and a memory for storing at least one Receive Buffer Descriptor which includes a pointer and a length value which defines a buffer in the memory for storing a packet which is to be transferred from one network to another network;
means in the first adapter for accessing a Receive Buffer Descriptor when it identifies a packet requiring transfer and for initiating transfer of the packet from the first adapter store into the memory buffer defined in the descriptor and for notifying the processor and its control program when a complete packet has been transferred to and stored in the processor memory;
means in the control program for examining the contents of the buffer and generating a Transmit Descriptor which includes at least one pointer and a length field defining the buffer;
and,
a second adapter connected to the said other network and responsive to the said at least one Transmit Descriptor for transmitting the packet stored in the buffer defined in the Transmit Descriptor.

3 more elements

Dependencies are inferred from the claim text.

Network bridge

Life of this patent

Network bridge

Life of this patent

Abstract

Claims6