ISTP & Ordinary URLs
The Media Grid will have the ability to unicast and multicast stream ordinary URLs through the grid from ordinary URL-based streams to the default portal. This section describes the syntax used to enable that operation by either a user of the default portal, or as referenced from a website URL. If a specific URL or website does not conform with InterStream's anti-piracy policy, those URLs may be blacklisted from the grid.
ISTP URL Syntax Translation and Compatibility
The syntax for ISTP must be compatible and extend the existing URL conventions. Therefore, it must observe the existing syntax of URLs while allowing it to be extended to support existing "off media grid" streaming objects as well as rich media objects that are registered within the grid. A review of the basic URL syntax rules follows.
While the syntax for the rest of the URL may vary depending on the particular scheme selected, URL schemes that involve the direct use of an IP-based protocol to a specified host on the Internet use a common syntax for the scheme-specific data: //<user>:<password>@<host>:<port>/<url-path> Some or all of the parts "<user>:<password>@", ":<password>", ":<port>", and "/<url-path>" may be excluded. The scheme specific data start with a double slash "//" to indicate that it complies with the common Internet scheme syntax. The different components obey the following rules: user An optional user name. Some schemes (e.g., ftp) allow the specification of a user name. password An optional password. If present, it follows the user name separated from it by a colon. The user name (and password), if present, are followed by a commercial at-sign "@". Within the user and password field, any ":", "@", or "/" must be encoded. Note that an empty user name or password is different than no user name or password; there is no way to specify a password without specifying a user name. E.g., <URL:ftp://@host.com/> has an empty user name and no password, <URL:ftp://host.com/> has no user name, while <URL:ftp://foo:@host.com/> has a user name of "foo" and an empty password. host The fully qualified domain name of a network host, or its IP address as a set of four decimal digit groups separated by ".". Fully qualified domain names take the form as described in Section 3.5 of RFC 1034  and Section 2.1 of RFC 1123 : a sequence of domain labels separated by ".", each domain label starting and ending with an alphanumerical character and possibly also containing "-" characters. The rightmost domain label will never start with a digit, though, which syntactically distinguishes all domain names from the IP addresses. port The port number to connect to. Most schemes designate protocols that have a default port number. Another port number may optionally be supplied, in decimal, separated from the host by a colon. If the port is omitted, the colon is as well. url-path The rest of the locator consists of data specific to the scheme, and is known as the "url-path". It supplies the details of how the specified resource can be accessed. Note that the "/" between the host (or port) and the url-path is NOT part of the url-path. The url-path syntax depends on the scheme being used, as does the manner in which it is interpreted.
Note: The following is a proposed syntax; Parameter passing of special characters have not been checked across all browsers which InterStream intends to support.
Extending RFC 1738
By extending RFC 1738 to support ISTP, it would be natural to follow the same syntax rules. ISTP has two forms: one for off Media Grid content referenced by a URL to be streamed by the grid; The other for natively referenced Handle Prefixes and Suffixes that is contained within the grid. ISTP determines from the first parameter as to whether to interprete and locate the content either on or off the grid. These two methods are defined as either:
Specifically, ISTP has the following form when being used to transfer an existing "off grid" referenced content via the URL into or through the Media Grid:
All other parameters remain consistent with RFC 1738. URLs which are interpreted by ISTP to be streamed through the media grid will be first located by the location resolution system. Ideally, the media grid's location resolution system will find the optimal Media Grid Elements to stream the URL's content through to maximize the quality of experience for the end user.
For "on grid" rich media objects, ISTP interprets a Handle prefix and suffix in either numeric or mnemonic form. Since the Handle System does not specify a mnemonic form for prefixes and suffixes, the Media Grid implementor will be responsible for creating and managing a registry to translate from the mnemonics into the prefix or suffix values. Therefore, Handle System objects will be interpreted by ISTP as follows:
In addition to the transfer-protocol prefixes, the "adult" and "InterStream" will be reserved for InterStream Industry Association licensing to vertical market segments and as useful defaults. InterStream may opt to reserve other prefixes for additional market segments and defaults in the future. InterStream will maintain a list of reserved-prefixes, defined below. Like domain names, reserved-prefixes are case insensitive.
Default Portals and Unrecognized Domain Names, URLs or Prefixes
If the browser is redirected to a default portal, the type of default portal will be determined by whether any subset of the character string after istp:// matches an explicit-phrase, defined below. If it does match, then the browser will be redirected to the "Default Adult Portal". Otherwise, the browser will be redirected to the "Default Mainstream Portal". The default portal url-path will have a string, "?handle=unrecognized", appended to the end of the URL when resolution occurs if the domain, URL, or prefix is unrecognized. Implicitly, the default portal url-path assumes that the user intended to be redirected to one of the default portals if either "adult" or "InterStream" is used as a prefix.
Other Potential Prefix Usage Conventions
In addition to explicit phrases, prefixes may be reserved or aliased. Reserved prefixes may be used by the InterStream Assocaition to define additional default portals for specific market segements. Currently, InterStream envisions the following potential vertical industry segments:
Prefixes may be aliased so that multiple mnenominc terms resolve to the same numeric Handle Prefix. This may useful for webmasters and others wishing to transition to ISTP from URL and domain name based conventions.
The following examples may help clarify how ISTP can transition usage from lower performance RFC 1738 type "off grid" URLs into higher performance Handles on the Media Grid.