Patent Application
20080279186
1. Field of the Invention
The present invention relates in general to the field of information handling system displays and networks, and more particularly to a system and method for communication of uncompressed visual information through a network.
2. Description of the Related Art
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
Information handling systems typically interact with end users through a visual display. The increasingly powerful components used in information handling systems have allowed presentation of visual images with high resolutions that use large numbers of pixels disposed in a display. High resolution images typically require large amounts of information with pixel values frequently refreshed at a display. Generally, in order to generate high resolution images, information handling systems compress the visual information until the visual information is rendered as pixel values for communication to a display. For example, pictures or videos are stored in compressed form, such as JPEG and MPEG formats, and, often, much of the processing for creating the visual images is performed by specialized components located in a graphics card. By keeping visual information compressed until it is rendered by the graphics card into pixel values, less bandwidth is used within the information handling system for communicating the visual information between processing components, such as from memory to the CPU or the graphics card. The rendered visual information typically proceeds from the graphics card to the display using display-specific connections, such as VGA or DVI connections. These display-specific connections are designed to keep a steady flow of uncompressed pixel-level visual information from the graphics card to the display controller, which directs the display pixels to present colors determined from the uncompressed visual information.
Recently, to increase the flexibility available when communicating uncompressed visual information to a display, industry has introduced the DisplayPort specification to define a digital I/O interface for internal and external display platforms. The DisplayPort specification provides an asynchronous bi-directional mechanism to deliver uncompressed digital packetized video streams over a two pair wire interface with pixel data encapsulated into 64 byte micropacket transport units. The transport units contain data, control and synchronization for an end device, known as a sink, which receives video from a single transmitting source device. DisplayPort sink devices store EDID information that is communicated from the sink device to the source device. Although the DisplayPort digital packetized architecture implies an ability to steer packets to different locations, version 1.1 of the DisplayPort specification only provides for a direct link between a single source and sink pair of devices, such as through a direct cable connection.
Therefore a need has arisen for a system and method which encapsulates uncompressed visual information packets for communication across a network architecture.
In accordance with the present invention, a system and method are provided which substantially reduce the disadvantages and problems associated with previous methods and systems for communication of uncompressed visual information packets across a network. A packet converter switch receives uncompressed visual information packets at a first set of display device ports and selectively directs the visual information to network ports based on an address resolution table stored on the switch. A packet converter encapsulates the uncompressed visual information packets into network packets for communication over a network.
More specifically, a packet converter switch has plural display device ports, such as DisplayPort ports, and plural network ports, such as Ethernet ports. Uncompressed visual information received at a display device port is selectively switched by a switch matrix to a network port based upon a lookup in an address resolution table that associates display device and network ports. A packet converter encapsulates the uncompressed visual information packets into network packets using an operation defined for the port in the address resolution table. The encapsulated packets are forwarded to the network port for communication through the network. For example, the network packets are sent through the Internet to another packet converter switch and accepted through a network port. The uncompressed visual information is extracted from the network packets and switched to a display device port based upon a lookup at an address resolution table stored on the switch. The association of ports is established with a packet converter policy engine that allows updates to the address resolution table, including definition of the operation to be performed upon information received at each port.
The present invention provides a number of important technical advantages. One example of an important technical advantage is that uncompressed visual information packets, such as DisplayPort packets, are encapsulated for communication through legacy networks that allow switching of the visual information to varied destinations. Visual information micropackets are switched, converted to legacy packets and regenerated as micropackets to support communication of uncompressed visual information to plural possible destinations. Placing uncompressed visual information into a network architecture provides for convenient presentation of visual information at a display distal to the rendering of the visual information without requiring a direct cable connection.
The present invention may be better understood, and its numerous objects, features and advantages made apparent to those skilled in the art by referencing the accompanying drawings. The use of the same reference number throughout the several figures designates a like or similar element.
Uncompressed visual information packets are adapted for communication between information handling systems and display devices over conventional networks by a packet converter switch. For purposes of this disclosure, an information handling system may include any instrumentality or aggregate of instrumentalities operable to compute, classify, process, transmit, receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, or other purposes. For example, an information handling system may be a personal computer, a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The information handling system may include random access memory (RAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional components of the information handling system may include one or more disk drives, one or more network ports for communicating with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, and a video display. The information handling system may also include one or more buses operable to transmit communications between the various hardware components.
Referring now to
The network packets traverse conventional network architecture, such as the Internet 34 or routers 36, to reach a network port of a second packet converter. Network packets received at a network port of packet converter switch 26 have the uncompressed visual information extracted for communication through a DisplayPort port 28 to a display device 22 for presentation. The association of the network port and DisplayPort port is determined by a map on the second packet converter switch 28 stored by interaction with a packet converter policy engine 32. The map on each packet converter switch 26 includes other relevant information to aid in the encapsulation and extraction operations, such as network address and DisplayPort sink address information as well as the operation to be performed on packets arriving at each port. In addition to encapsulation and extraction operations, native switching of visual information supported between related ports, such as at layer 2 or layer 3 levels on Ethernet network ports 30. Further, bi-directional DisplayPort functions are supported, such as communication of EDID information from a display 22 to an information handling system 10 by reference to mapping information on a packet converter switch to correctly switch information sent from a sink to a source device.
Referring now to
As an example, uncompressed DisplayPort packets of visual information that arrive at a port 28 result in a lookup of the port in address resolution table 46 by switching matrix 44. The lookup identifies the port 28 or 30 that receives the visual information and the operation to be performed on the visual information. For uncompressed visual information packets received at a DisplayPort port that are communicated to a network port, the DisplayPort to Ethernet function 50 is used to encapsulate the visual information into network packets, such as with address information available in address resolution table 46. As an alternative example, network packets arriving at an Ethernet port 30 result in a lookup of the Ethernet port that receives the network packet in address resolution table 46 for the port that will receive the information and the function to be performed on the network packet. If a DisplayPort port 28 is to receive visual information encapsulated in the network packet, then the Ethernet to DisplayPort function 52 extracts the uncompressed visual information packets from the network packets and forwards the visual information to the associated port 28. In some instances, DisplayPort control information will be communicated instead of visual information, such as EDID information from a display device to an information handling system. In other instances, where DisplayPort information proceeds to another DisplayPort port 28, or where Ethernet information proceeds to another Ethernet port 30, native function 54 supports switching between desired ports without conversion functions.
Referring now to
Although the present invention has been described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the invention as defined by the appended claims.
