Exposing a bridged network as a single virtual segment

• US 20060010265A1
• Filed: 06/29/2005
• Published: 01/12/2006
• Est. Priority Date: 10/30/2000
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Pall, Gurdeep S., Morgan, Dennis A., Aiken, Mark A.
• Granted Patent: US 7,616,633 B2
• Time in Patent Office: Days
• US Class Current: 710/33
• CPC Class Codes: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 49/901 using storage descriptor, e.g. read or write pointers
• CPC Class Codes: H04L 69/32 Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A software network bridge is disclosed which allows the connected network segments to be presented as a single network unit to the host computer. The software bridge can be implemented as an intermediate network driver, abstracting multiple network segments into a single network interface for higher level protocols and applications. While the intermediate network driver acts as a software bridge implementing the Spanning Tree Algorithm, it also acts a network interface driver to higher level protocols, conglomerating information from the multiple underlying network interface cards and forwarding along commands from the higher level software to the appropriate network interface card. The intermediate network driver can also simultaneously send the same data packet through multiple network interfaces by creating multiple packet descriptors, each pointing to the same data, but each given individually to the underlying network interfaces to control during their transmission. Further efficiencies can also be achieved by the software bridge, implemented as an intermediate network driver, through the use of a dynamic allocation scheme which increases the size of the useable buffers of each network interface without increasing the overall memory consumption, and the use of a queuing scheme which preliminarily examines incoming data packets to determine if any processing needs to be performed, and queues the packets should they require processing. Additionally, a user interface is presented exposing this functionality of the intermediate network driver.

Claims

1. A method of multiply referencing an element of data, the method comprising:

creating a base descriptor of the element of data, wherein the base descriptor contains a counter and a pointer to the element of data;

creating a child descriptor of the element of data, wherein the child descriptor contains a pointer to the base descriptor and the pointer to the element of data;

modifying the counter to account for the child descriptor;

providing access to the element of data to a first user of the element of data by providing to the first user the base descriptor; and

simultaneously providing access to the element of data to a second user of the element of data by providing to the second user the child descriptor.

2. A computing device for performing the steps of claim 1.

3. The method of claim 1 wherein the creating the base descriptor of the element of data includes modifying the counter to account for the base descriptor.

4. The method of claim 1 further comprising:

discarding the base descriptor if the counter indicates the existence of zero child descriptors.

5. The method of claim 1 wherein the base descriptor further contains a pointer to an original descriptor received with the element of data.

6. The method of claim 1 wherein:

the element of data is a multiple destination packet directed to more than one computing device on a network;

the base descriptor of the element of data is a base packet descriptor; and

the child descriptor of the element of data is a child packet descriptor;

the method of claim 24 further comprising;

determining the more than one computing device on the network to which the multiple destination packet is directed;

determining multiple ports through which the more than one computing device on the network can be reached;

transmitting the multiple destination packet through a first of the multiple ports by providing to the first of the multiple ports the base packet descriptor; and

simultaneously transmitting the multiple destination packet through a second of the multiple ports by providing to the second of the multiple ports the child packet descriptor.

7. The method of claim 6 wherein the creating the child packet descriptor includes creating multiple child packet descriptors sufficient to simultaneously provide each of the multiple ports with a one child packet descriptor of the multiple child packet descriptors or the base packet descriptor.

8. The method of claim 6 wherein:

the transmitting the multiple destination packet through the second of the multiple ports by providing to the second of the multiple ports the child packet descriptor includes discarding the child packet descriptor when the transmitting the multiple destination packet through the second of the multiple ports has completed and modifying the counter when the child packet descriptor is discarded;

the transmitting the multiple destination packet through the first of the multiple ports by providing to the first of the multiple ports the base packet descriptor includes, if the counter indicates that no child packets exist, discarding the base packet descriptor when the transmitting the multiple destination packet through the first of the multiple ports has completed and returning the multiple destination packet.

9. A computer-readable medium having computer executable instructions for performing steps for multiply referencing an element of data, the steps comprising:

creating a base descriptor of the element of data, wherein the base descriptor contains a counter and a pointer to the element of data;

creating a child descriptor of the element of data, wherein the child descriptor contains a pointer to the base descriptor and the pointer to the element of data;

modifying the counter to account for the child descriptor;

providing access to the element of data to a first user of the element of data by providing to the first user the base descriptor; and

simultaneously providing access to the element of data to a second user of the element of data by providing to the second user the child descriptor.

10. The computer-readable medium of claim 9 wherein the creating the base descriptor of the element of data includes modifying the counter to account for the base descriptor.

11. The computer-readable medium of claim 9 further comprising:

discarding the base descriptor if the counter indicates the existence of zero child descriptors.

12. The computer-readable medium of claim 9 wherein the base descriptor further contains a pointer to an original descriptor received with the element of data.

13. The computer-readable medium of claim 9 wherein:

the element of data is a multiple destination packet directed to more than one computing device on a network;

the base descriptor of the element of data is a base packet descriptor; and

the child descriptor of the element of data is a child packet descriptor;

the computer-readable medium of claim 53 further having computer executable instructions for performing steps comprising;

determining the more than one computing device on the network to which the multiple destination packet is directed;

determining multiple ports through which the more than one computing device on the network can be reached;

transmitting the multiple destination packet through a first of the multiple ports by providing to the first of the multiple ports the base packet descriptor; and

simultaneously transmitting the multiple destination packet through a second of the multiple ports by providing to the second of the multiple ports the child packet descriptor.

14. The computer-readable medium of claim 13 wherein the creating the child packet descriptor includes creating multiple child packet descriptors sufficient to simultaneously provide each of the multiple ports with a one child packet descriptor of the multiple child packet descriptors or the base packet descriptor.

15. The computer-readable medium of claim 13 wherein:

the transmitting the multiple destination packet through the second of the multiple ports by providing to the second of the multiple ports the child packet descriptor includes discarding the child packet descriptor when the transmitting the multiple destination packet through the second of the multiple ports has completed and modifying the counter when the child packet descriptor is discarded;

the transmitting the multiple destination packet through the first of the multiple ports by providing to the first of the multiple ports the base packet descriptor includes, if the counter indicates that no child packets exist, discarding the base packet descriptor when the transmitting the multiple destination packet through the first of the multiple ports has completed and returning the multiple destination packet.