\section{Syntax}
\label{sec:syntax}

The RTSP syntax is described in an augmented Backus-Naur form (BNF) as
used in RFC 2068 (HTTP/1.1). 

\subsection{Base Syntax}

\begin{verbatim}
OCTET     = <any 8-bit sequence of data>
CHAR      = <any US-ASCII character (octets 0 - 127)>
UPALPHA   = <any US-ASCII uppercase letter "A".."Z">
LOALPHA   = <any US-ASCII lowercase letter "a".."z">
ALPHA     = UPALPHA | LOALPHA
DIGIT     = <any US-ASCII digit "0".."9">
CTL       = <any US-ASCII control character
             (octets 0 - 31) and DEL (127)>
CR        = <US-ASCII CR, carriage return (13)>
LF        = <US-ASCII LF, linefeed (10)>
SP        = <US-ASCII SP, space (32)>
HT        = <US-ASCII HT, horizontal-tab (9)>
<">       = <US-ASCII double-quote mark (34)>
CRLF      = CR LF
LWS       = [CRLF] 1*( SP | HT )
TEXT      = <any OCTET except CTLs>
tspecials = "(" | ")" | "<" | ">" | "@"
          | "," | ";" | ":" | "\" | <">
          | "/" | "[" | "]" | "?" | "="
          | "{" | "}" | SP | HT
token = 1*<any CHAR except CTLs or tspecials>
quoted-string = ( <"> *(qdtext) <"> )
qdtext = <any TEXT except <">>
quoted-pair = "\" CHAR

message-header = field-name ":" [ field-value ] CRLF
field-name = token
field-value = *( field-content | LWS )
field-content = <the OCTETs making up the field-value and consisting
		 of either *TEXT or combinations of token, tspecials,
		 and quoted-string>
\end{verbatim}
