Bergh B, Pietsch M, Schlaefke A, Garcia I, Vogl T J
Department of Information and Communication Technology, Klinikum der Johann Wolfgang Goethe Universität, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
Eur Radiol. 2004 Mar;14(3):526-33. doi: 10.1007/s00330-003-2059-5. Epub 2003 Oct 3.
The aim of this study was to assess the up- and download performance of an image Web system (IWS) during simultaneous up- and download procedures. Following preparatory tests, the upload capacity (UC) with and without simultaneous download and the time-to-display (TTD) with and without simultaneous upload were determined for different image, server and compression types, and with up to 16 concurrent clients. The UC varied between 1.7-5.5 Gigabyte per hour (GB/h) and was slightly influenced by a simultaneous download; however, the TTDs were substantially prolonged during an upload and only below 5 s with up to four to six concurrent clients. The choice of image and server type had a strong impact on UC and TTD. Lossy primary compression proved slightly superior. An effective UC of approximately 4.0 GB/h or 96 Gigabyte per day (GB/day) can be achieved, which appears suitable even for large institutions. Because of its substantial influence on UC and TTD during simultaneous up- and download, the server hardware should be equipped with two processors and 1 GB RAM. Lossy primary compression may be used with slight performance benefits when full-resolution images are not required. The upload is a time-demanding process, and it is possible that during peak hours the waiting times are unacceptable for clinicians.
本研究的目的是评估图像网络系统（IWS）在同时进行上传和下载操作时的上传和下载性能。在进行预备测试后，针对不同的图像、服务器和压缩类型，以及多达16个并发客户端，分别测定了有无同时下载时的上传容量（UC）以及有无同时上传时的显示时间（TTD）。UC在每小时1.7 - 5.5千兆字节（GB/h）之间变化，同时下载对其有轻微影响；然而，上传期间TTD会大幅延长，只有在多达四到六个并发客户端时才会低于5秒。图像和服务器类型的选择对UC和TTD有很大影响。有损主压缩显示出略优的性能。可以实现约4.0 GB/h或每天96千兆字节（GB/天）的有效UC，这对于大型机构似乎也是合适的。由于在同时上传和下载期间对UC和TTD有重大影响，服务器硬件应配备两个处理器和1 GB内存。当不需要全分辨率图像时，有损主压缩的使用可能会带来轻微的性能提升。上传是一个耗时的过程，在高峰时段临床医生的等待时间可能会变得无法接受。
