XMPP 如何在没有任何中间跃点的情况下在两个不同服务器（不同域）之间传输消息？
How XMPP transfer messages between two different servers(of different domains) without any intermediate hops?
我的团队想要构建一个聊天应用程序，因此我们正在研究我们的武器库中可用的所有可用技术。我担心 XMPP。所以我正在阅读 Oreilly 的“XMPP：权威指南”，并遇到了这些行，我引用
In XMPP, messages are delivered as fast as possible over the network. Let’s say that Alice sends a message from her new account on the wonderland.lit server to her sister on the realworld.lit server. Her client effectively “uploads” the message to wonderland.lit by pushing a message stanza over a client-to-server XML stream. The wonderland.lit server then stamps a from address on the stanza and checks the to ad- dress in order to see how the stanza needs to be handled (without performing any deep packet inspection or XML parsing, since that would eat into the delivery time). Seeing that the message stanza is bound for the realworld.lit server, the wonderland.lit server then immediately routes the message to realworld.lit over a server-to-server XML stream (with no intermediate hops).第 45 页
Like email, but unlike the Web, XMPP systems involve a great deal of inter-domain connections. However, when you send an XMPP message to one of your contacts at a different domain, your client connects to your “home” server, which then connects directly to your contact’s server without intermediate hops (see Figure 2-4).第13页
任何人都可以让我明白为什么没有中间跃点（不像电子邮件）。
E-Mail (SMTP) 也没有中间跃点。我假设您混淆了 XMPP、SMTP 等所在的应用程序 OSI 层与网络层 (IP)。
我的团队想要构建一个聊天应用程序，因此我们正在研究我们的武器库中可用的所有可用技术。我担心 XMPP。所以我正在阅读 Oreilly 的“XMPP：权威指南”，并遇到了这些行，我引用
In XMPP, messages are delivered as fast as possible over the network. Let’s say that Alice sends a message from her new account on the wonderland.lit server to her sister on the realworld.lit server. Her client effectively “uploads” the message to wonderland.lit by pushing a message stanza over a client-to-server XML stream. The wonderland.lit server then stamps a from address on the stanza and checks the to ad- dress in order to see how the stanza needs to be handled (without performing any deep packet inspection or XML parsing, since that would eat into the delivery time). Seeing that the message stanza is bound for the realworld.lit server, the wonderland.lit server then immediately routes the message to realworld.lit over a server-to-server XML stream (with no intermediate hops).第 45 页
Like email, but unlike the Web, XMPP systems involve a great deal of inter-domain connections. However, when you send an XMPP message to one of your contacts at a different domain, your client connects to your “home” server, which then connects directly to your contact’s server without intermediate hops (see Figure 2-4).第13页
任何人都可以让我明白为什么没有中间跃点（不像电子邮件）。
E-Mail (SMTP) 也没有中间跃点。我假设您混淆了 XMPP、SMTP 等所在的应用程序 OSI 层与网络层 (IP)。