我正在寻找 Lync 2010 的客户端和服务器端 API。但我发现许多 API 可以开发。任何人都有什么区别？请帮忙
Microsoft Lync Server 2010 SDK http://www.microsoft.com/downloads/en/details.aspx?FamilyID=58ccf6fd-31db-4f15-bafb-c5ef28afc5fc
Microsoft 统一通信托管 API 3.0 软件开发工具包 http://www.microsoft.com/downloads/en/details.aspx?FamilyID=4493BAAB-6214-4770-8CF9-69C813E8A9FA
Microsoft 统一通信客户端 API SDK
http://www.microsoft.com/downloads/en/details.aspx?FamilyID=82c468da-3294-4ca9-bbcc-d455cfd06af2
Lync 2010 SDK是 Lync 2010 的最新客户端 SDK（不适用于以前的版本）。它是一个完全托管（即 .Net）的 API，允许您构建应用程序来自动运行 Lync 实例以执行任务，例如显示状态并从您的 LoB 应用程序开始对话（自动化模式）。它还允许您构建自己的自定义客户端以完全替换 Lync UI（UI 抑制模式）。
Unified Communications Managed API 3.0 (UCMA) 是 Lync 2010 的最新服务器端 SDK（不适用于以前的版本）——它也是一个完全托管的 API，允许您构建注册到 Lync 作为端点的应用程序。这对于构建机器人很有用，例如，当股票价格超过某个阈值时，它会向人们发送即时消息的股票行情机器人。您还可以使用它构建呼叫路由和 IVR（交互式语音响应）应用程序，它可以使用 Windows Workflow Foundation 来减少您必须编写的代码量。
Lync Server 2010 SDK is another server-side SDK, but rather than creating endpoints as per UCMA, this allows you to write filters that plug in to a Front End server. A filter allows you to inspect SIP traffic as it passes through the server, so its useful for building e.g. archiving solutions.
Unified Communications Client API (UCCA) is a client side API that allows you to build custom endpoints - e.g. Lync client replacements. This is best avoided, as it is COM based, so you have a lot more code to write, and need to be very careful about memory leaks. Its recommended to use Lync SDK in UI Supression mode, instead of this API. One benefit it does have though, is it works against Communicator 2007, Communicator 2007 R2 and Lync.
If you're developing against Lync and no previous versions, then Lync SDK (client) and UCMA 3.0 (server) should give you what you need. Otherwise, this article here talks about the previous SDKs in a bit more detail
Edit: I've expanded on this in a blog post
The main difference for me between Unified Communications Client API and UCMA was that UCC supports digest auth and that's why it is possible to build sip/rtp client for linux based asterisk.