保证你的流媒体资产安全

DRM is a hot acronym; ignore it at the risk of your Internet economic future.

网络营销和媒体销售的潜在效益已经实现, and with broadband implementation growing ineluctably, 互联网完全商业化的主要障碍不再是技术, but the absence of a ubiquitous way to protect digital property and profits.

While our concentration is on DRM for streaming media, this is actually only one part of the DRM puzzle: both the security of, and managing the marketing and distribution of downloadable data, constitute a much larger segment of the new industry, though there is a lot of crossover between the two areas.

InterTrust

A good example of a company concentrating on secure downloads is InterTrust科技公司. 成立于1990年, InterTrust是这个领域最老的玩家, 并且可能拥有最全面的系统来保护所有的数字数据, 不仅仅是数字媒体. InterTrust安装了一个“InterRights Point”,在客户的PC上进行DRM处理, 远程管理客户的数字版权. InterRights点将受保护的信息加密并存储在“DigiBox容器”中，只有当用户的计算机已被设置为满足提供商规则的InterRights点时，用户的计算机才能下载该容器. The files in a DigiBox container are protected even after they're played, and the protection persists even if files are sent to another consumer. 没有InterRights Point软件的潜在消费者将被提示在提供商的站点获得认证, thus allowing "superdistribution" of the media, yet providing persistent protection for the provider.

互惠

Exemplifying the business management aspect of DRM is 互惠 娱乐. Founded four years ago to function as a digital clearinghouse, 互惠创建和分发许可证，帮助跟踪和控制其客户的数字内容分发.

互惠的技术首先允许提供者设置访问规则，并允许使用者访问文档所需的要求. Permits can be free, traded for 信息 or issued as part of a transaction. 当消费者下载时，互惠软件会检查消费者的计算机是否有许可证. If none exists, the user is prompted to buy one. 在付款, the 互惠 Digital Clearing Service sends the permit to the consumer, 谁可以查看媒体. 审计记录被发送到互惠, 谁用它来生成跟踪报告——包括人口统计和购买数据——并分发付款.

流媒体的防御机制

Some aspects of both of these schemes can work with both downloadable and streaming media, 但流媒体也有自己的需求, 有些公司专门从事这方面的工作.

流媒体具有一定程度的内置安全性:大多数商业播放器不会将流文件保存到用户的磁盘上. While this is enough to prevent the most casual of thefts, with only a somewhat greater degree of piratical ambition, 任何人都可以创建或下载一个自定义播放器——称为“屏幕刮板”——它可以保存屏幕上显示的任何内容. 窃取流媒体材料的另一种方法是通过声音/视频卡重新数字化模拟音频和视频信号输出. Both these procedures render a degraded version of the original, but as bandwidth and technology improve the quality of streamed media, 海盗可以抢到的产品, 在理论上, 也要提高. 更老练的小偷, 当然, can find ways to download the original files from a streaming provider's server, but this problem is shared by anyone with assets on an online server.

都

也许这里新来的孩子是 都Technologies (原Internet Direct Media, Inc ..) Widevine concentrates exclusively on securing streaming media, 不下载, 但也包括一个管理功能. 本月初, Widevine introduced its streaming security solution, 数字, designed to protect the provider's rights in all popular streaming technologies, remaining invisible to both provider and consumer. 要做到这一点, Widevine将其软件放入硬件桥接器中，监控从服务器流出的任何内容，并动态地为每个流文件添加保护.

该公司创始人布莱恩·贝克说，Widevine保护的文件可以很容易地通过所有防火墙和其他网络障碍. 该公司还分发了一个安装在客户端的小软件“shim”. "This shim handles both security and decryption. It works on the fly and is transparent to the user, processing each file uniquely each time it streams,贝克说。.“我们还可以通过垫片设置的双向通道监控客户端的性能和安全性.贝克补充道, "This moves 信息 about a transaction back to a file server or e-commerce server, 允许内容提供商进行监控或微计费，如按分钟付费或按次付费."

Only when the streamed file reaches the client computer does decryption occur, 由文件流软件执行. 该软件监控客户端机器的企图破解流文件与屏幕刮板技术. 如果检测到此类操作, widevine软件关闭了流, 防止进一步的黑客攻击.

"Since our technology resides on small bridge between the media server and the network, we're outside the streaming servers themselves, 我们可以是格式不可知的，可以支持任何类型的服务器流:达尔文, 苹果QT, RealServer或其他任何东西,贝克说。.

Although its client negotiations are still under wraps, Widevine is in the process of securing business from large media studios, 大型主机和网络提供商, 流媒体服务公司. 贝克说，这项技术已经, “这对使用互联网作为广播媒介的媒体公司和使用互联网或内部网进行公司间通信(如敏感的高管广播)的公司具有重大影响。, 远程学习和其他材料."

SecureMedia

第二种方法体现在 SecureMedia. 创始人兼首席执行官杰克·奥斯瓦尔德表示, 公司成立之初, “我们没有那么关注数字媒体, 但是关于密码学. We began concentrating on streaming media about two and a half years ago, 但我们的密码学背景仍然是区分我们和其他人的基础. We come at it from the bit-scrambling approach."

SecureMedia has so far focused on working with RealServer applications but, 奥斯瓦尔德补充道, they could easily implement their technology with other formats. SecureMedia的方法是在流开始之前对要在服务器上传输的文件进行编码. Decryption occurs via a plug-in to the RealPlayer, 当用户访问作为SecureMedia客户端的提供商的站点时，哪些用户可以安装. Oswald说，这可以防止屏幕抓取，因为没有屏幕抓取播放器将有插件. 此外, he pointed out that screen-scraping inevitably yields degraded copies, 更令人担忧的是，盗版者会“侵入tcp/ip协议栈”，盗取一份优质的数字拷贝. The SecureMedia plan ensures that all media at the digital level is encrypted.

关于通过模拟路由的盗版, 奥斯瓦尔德说, “去年我们花了很多时间与五大网络的技术主管交谈，以确保我们了解他们的需求," and they were unconcerned about this threat. 他还指出，在不久的将来，交付平台将不会是一台包含各种盗版工具的电脑. 该媒体不会在个人电脑上使用，而是用于家庭娱乐中心，这需要一个可验证的设备，以保护所有者的权利." The device will enable streaming into home entertainment systems. 鉴于此, Oswald believes the biggest threat of piracy will be people who build settop decoders,“就像今天的卫星解码器. They might use some device that lets people tune in for free."

Vyou

使用的DRM设备 Vyou.com 操作简单的. 它可以与所有受欢迎的球员, and if a user clicks outside of the streaming window, 媒体立即停止流媒体. 这可以防止随意, 数字盗版, but does not extend to recording the analog output onto a connected device.

In addition to entertainment and other media streamed to the general consumer, Vyou专注于提供给特定客户用于特定目的的有价值的文档. 我是史蒂夫·兰道, 以嘉信理财为例, or some other financial institution that shows important material to a select audience. "This used to be done on paper handouts which were collected at the end of a meeting. It's trickier to do this on the Web," adds Landau.

Landau提到的另一个危险是“如果文件的路径包含在原始流文件中，那么有些人可以到达服务器并获取原始文件, or they can get it with some kind of hijacker file." Vyou's technology is also designed to prevent this kind of release of an original file, 以及Vyou服务器发布的版本.

等待洗牌

Each approach in this new industry has its own strengths and weaknesses, 不可避免的洗牌尚未发生. 这里最有趣和最普遍的因素之一是，各方似乎都不理会通过模拟录音途径进行盗版. 这可能是由于当今流媒体的质量并不是那么好. 这意味着任何流媒体材料, 先转换为模拟再转换为数字，必然会成为“垃圾进垃圾出”的牺牲品, 至少在某种程度上是这样. 尽管如此, 数以百万计的美元正在努力改变这种情况下的薄弱环节——媒体的质量, 不是再转换. And the moment that high-quality streaming makes the conversion process acceptable, 可以肯定的是，盗版者将会把流媒体从输出端口传输到输入端口, creating pretty good digital copies of the original.

电影制片厂和唱片公司认为，原版和这种复制品之间的质量差异是他们的保障. 仍然, people have historically embraced delivery systems from MP3 to small black and white TVs, 到更小的调幅收音机, despite the less-than-perfect reproduction quality of these media. 如果结果是内容, 而不是媒体, 信息到底是什么, 我们将迎来一个有趣的时代.