Debian provides a wide range of Real-Time Communications (
RTC) client software. The setup of RTC servers is discussed in
第 11.8 节 “实时通信服务”. In
SIP (Session Initiation Protocol) terminology, a client application or device is also referred to as a user agent.
Each client application varies in functionality. Some applications are more convenient for intensive chat users while other applications are more stable for webcam users. It may be necessary to test several applications to identify those which are most satisfactory. A user may finally decide that they need more than one application, for example, an XMPP application for messaging with customers and an IRC application for collaboration with some online communities.
为了最大化的提升用户在宽广的世界里沟通联络，建议同时配置 SIP 客户端程序和 XMPP 的客户端程序，或者是一个单独的同时支持两种协议的客户端程序。
The default GNOME desktop suggests the Empathy communications client. Empathy can support both SIP and XMPP. It supports instant messaging (IM), voice and video. The KDE project provides KDE Telepathy, a communications client based on the same underlying Telepathy APIs used by the GNOME Empathy client.
Popular alternatives to Empathy/Telepathy include Ekiga, Linphone, Psi, Jitsi and Jami (formerly known as Ring).
Jitsi requires no client other than a web browser. It support encrypted calls, and there is a huge list of public instances. There is no official Debian package for Jitsi, but it can be downloaded from their official website.
Some of these applications can also interact with mobile users using apps such as Lumicall on Android.
