service: client with umode +S. This implies that it is on a services server.
+The initiator sends the PASS, CAPAB and SERVER messages. Upon receiving the
+SERVER, the listener will check the information, and if it is valid, it will
+send its own PASS, CAPAB and SERVER messages, followed by SVINFO and the burst.
+Upon receiving the SERVER, the initiator will send SVINFO and the burst. If
+ziplinks are used, SVINFO is the first compressed message.
+The burst consists of SID and SERVER messages for all known servers, UID or
+EUID messages for all known users (possibly followed by ENCAP REALHOST, ENCAP
+LOGIN and/or AWAY) and SJOIN messages for all known channels (possibly followed
+D (deaf: does not receive channel messages)
parameters: space separated capability list
-Sends capabilities of the server. This must include QS and ENCAP.
+Sends capabilities of the server. This must include QS and ENCAP. It is also
+strongly recommended to include EX, CHW, IE and KNOCK, and for charybdis TS6
+also SAVE and EUID. For use with services, SERVICES and RSFNC are strongly
+The capabilities may depend on the configuration for the server they are sent
-parameters: origin, destination server
+parameters: origin, destination server
-Sends a PING to the destination server, which will reply with a PONG.
+Sends a PING to the destination server, which will reply with a PONG. If the
+destination server parameter is not present, the server receiving the message
-The origin field is not used in the server protocol.
+The origin field is not used in the server protocol. It is sent as the name
+(not UID/SID) of the source.
Remote PINGs are used for end-of-burst detection, therefore all servers must