CCSO Nameserver

A CCSO name-server or Ph protocol was an early form of database search on the Internet. In its most common form it was used to look up information such as telephone numbers and email addresses. Today this service has been largely replaced by . It was used mainly in the early-to-middle 1990s. The name-server was developed by Steve Dorner at the University of Illinois at Urbana–Champaign, at the university's Computing and Communications Services Office (CCSO).

There also exists an Outlook plugin and standalone application known as OutlookPH

The name-server directories were frequently organized in hierarchies. The tools "Ph" and "Qi" were the two components of the system: Ph was a client that queried the Qi server.

The Ph protocol was formally defined by RFC 2378 in September 1998. However the memo issued at this time references its prior use for an unspecified period of time before this date. It defines sixteen keywords that can be used on the server side to define record properties. It also defines how clients should access records on the server and what responses the server should give. Ph server communication takes place on port 105.

All commands and response are initially assumed to be in US-ASCII encoding for historical reasons, unless the client explicitly asks for 8-bit (ISO-8859-1) encoding. As a result, only characters between 0x20 and 0x7E are initially sent by the server in raw form. Other characters, if present in entries, will be escaped using the RFC 2045 defined "Quoted-Printable" encoding. The initial request from the client is a text base keyword optionally followed by one or more parameters as defined in the RFC 2378. The server then responds to the request. The following example response to a status request is provided by the RFC memo.

Each command defined by the RFC 2378 memo consists of a keyword followed as needed by one or more parameters or key words. They can be separated by spaces tabs or the end of the line. Each line must be terminated in CR+LF style.

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