Apple Inc.

Ted W Walker

Kevin W Andresen

Robert C Fishman

Allen M Chan

Paul E Reilly

A modified stream-based protocol implementation is employed within a network environment to compensate for inefficiencies associated with conventional stream based protocols, such as TCP. Characteristics of a transaction-based protocol are advantageously utilized in client/server data transactions to reduce the number of acknowledgment signals sent upon receipt of data, as well as eliminate delays associated with the buffering of data at the server. These results are accomplished without requiring changes to servers using standard stream-based protocols.

Data transmission utilizing pre-emptive acknowledgements with transaction-oriented protocols

Optimized performance for transaction-oriented communications using stream-based network protocols

A printing system is provided for interfacing one or more session level protocols within the system to achieve an enhanced communications between the host computer and the network printer. A client server connection protocol (CSCP) facilitates this connectivity by providing a symmetric protocol for connections between servers and clients over connection-based stream-oriented protocols such as AppleTalk Data Stream Protocol (ADSP) and Transmission Control Protocol (TCP). CSCP resides in the presentation layer of the OSI seven-layer model and interfaces with one or more session level protocols. The dynamic port negotiation of CSCP facilitates concurrency for server applications by off-loading the port negotiation that would otherwise have to take place by the server and its clients. Thereby, CSCP allows the printing system to be easily extended and integrated with new protocol/ports as they are developed and introduced.

Client server symmetric presentation-layer connection protocol for

A network printing system is provided for allowing a single channel connection to support multiple channel connections when implemented over a direct connect, non-network device. More particularly, a socket simulation protocol (SSP) is incorporated into the printing system for providing multiple data paths for allowing serial based host drivers to interact with the network printer in the same synchronous model as in multiple connection based drivers. SSP enables a normalized interface to the printing system so that various heterogeneous network services protocol/ports may interact in the same way and for also enabling new protocol/ports to be easily extended and integrated into the network printing system.

Socket simulation protocol for network printing systems

An architecture for a network printing system is provided that allows the network printer to achieve and enhance two-way communication between the host computers and the printer connected to the network. The architecture layers provide a normalized interface to the layers below so that all of the protocol/ports interact in the same way. More particularly, an imaging device protocol (IDP) and an IDP emulator enable various network service protocol/ports, both IDP and non-IDP ports, to communicate with the network printer by 'seamless plug and play' connectivity. Furthermore, this architecture allows host computers to request network printer services through a client service connection protocol (CSCP) and IDP when these protocols are supported and emulates CSCP/IDP interactions when the network services do not support the CSCP/IDP protocols so that print job requests may be executed from the same print queue. This architecture also may be easily extended and integrated with new protocol/ports as they are developed and introduced.

Architecture for network printing systems

An image to be generated is analyzed to determine whether it is comprised solely of bi-level color data. If so, an indication is provided to a rendering device that a simpler rendering procedure, suitable for bi-level data, can be employed. However, full color information pertaining to the image is retained. If the rendering device is able to process the image data in a bi-level format, it does so, to thereby improve performance and reduce the amount of memory capacity that is required. If multi-level data is detected, the bi-level data is expanded and full color rendering is carried out in a conventional fashion.

Method and system for selectively rendering image data in a bi-level or

To reduce rendering time for an image to be generated, an image to be generated, such as a page of a document, is divided into non-overlapping regions. Within each region, a determination is made whether all of the data contained therein is achromatic. If so, achromatic data is rendered for a single component of a multi-component color space. Pixel values are stored in one section of a frame buffer that relates to the single component. The other components of the color space use multiple references to the pixel data stored in this one section, rather than being separately rendered.

Method and system for rendering achromatic image data for image output

A system and method are provided for a printer which divides raw bands of print data corresponding to a page to be printed into a plurality of sub-bands. By generating sub-bands of print data for each page, a segmented page frame buffer can be used to store the print data non-contiguously in the memory segments of the buffer so that the memory may be used more efficiently. Also, a compressed data line representative of blank data is stored in the memory for eliminating redundant operations of processing and storing blank data lines (data lines containing no data). As a result, every time a blank data line is detected, the compressed blank data line stored in the memory can be pointed to and the performance of the printer is enhanced by reducing the printing time.

Growing community of inventors

Sunnyvale, CA, United States of America

Ted W Walker