Twisted is an event-based framework for Internet applications. It includes a Web server, an SMTP/POP3 server, a telnet server, an SSH server, an IRC server, a DNS server, a generic client/server pair for remote object access (Perspective Broker), and APIs for creating new protocols. It supports integration with GTK+, GTK+ 2, Qt, Tkinter, wxPython, Mac OS X (PyObjC) and Win32 event loops. It also supports TCP, SSL and TLS, UDP, Unix sockets, multicast, and serial ports. Supported protocols include HTTP, FTP, SMTP, POP3, IMAP, TOC, OSCAR (AIM and ICQ), SSH, DNS, IRC, NNTP, Jabber, SOCKSv4, Telnet, SIP (for VoIP), and XML-RPC and SOAP using external packages. Most protocols are supported as both servers and clients.
Jigsaw is W3C's leading-edge Web server platform, providing a sample HTTP 1.1 implementation based on RFC2616 and a variety of other features on top of an advanced architecture implemented in Java. Jigsaw provides both client and server HTTP/1.1 implementations, is fast, easy to extend, flexible, and is also packaged as a ready-to-run HTTP/1.1 proxy-cache.
muhttpd (mu HTTP deamon) is a simple but complete Web server written in portable ANSI C. It supports static pages, CGI scripts, and MIME type based handlers. It drops privileges before accepting any connections, and can log received requests. It has been tested on OpenBSD, GNU/Linux, NetBSD, FreeBSD, Mac OS X, and Cygwin. It runs successfully on 32-bits, 64-bit, little endian, and big endian systems.
Twisted Web includes an HTTP/1.0 protocol implementation for both servers and clients. It also includes a resource framework for implementing rich, dynamic web applications. It includes support for authentication either via HTTP AUTH, session URLs, or session cookies. It supports CGIs and a custom PB-based distribution mechanism for serving content from separate, persistent processes. It includes SOAP and XML-RPC support for both clients and servers. It also makes it particularly easy to deploy new servers with novel or ephemeral use-cases, often with only a single short command.