LSL Protocol/Restrained Love Open Relay Group/ORG Requirements

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STATUS: draft

VERSION: 0001

Definition of an ORG device

A RLVR device is compliant with ORG specifications version 0001 if

  • it implements Marine Kelley's RLVR protocol version 1.100
  • it implements the !x-orgversions meta-command as defined below
  • it implements the protocol fixes below
  • all metacommands it supports are of the following types:
  • meta-commands in RLVR protocol, behaving as described in RLVR specifications
  • meta-commands, whose names start with "!x-", behaving as described in ORG specifications
  • proprietary or experimental metacommands, whose names start with "!_-" (replace "_" by any letter that is not "x")

ORG devices may be advertised by the use of the ORG logo for advertising compliance with ORG requirements. ORG devices makers are encouraged to do so.

!x-orgversions

This meta-command purpose it twofold. First it allows a controlling device to ask a relay for the list of ORG x-tensions it supports, second it is similar to !version in RLVR protocol, as its relpy gives the versions of the ORG core specification and ORG x-tensions that are implemented in the relay.

C<->R
  ->   query,rUUID,!x-orgversions
 <-    query,cUUID,!x-orgversions,ORG=0001/who=001/email=005

The acknowledgement string of the relay is a list separated by "/" whose items are of the form <package>=<version>. The first package is "ORG", the core specification of ORG relays, its version string is the version of the specification (4 digits). The other packages are ORG x-tension names (not meta-command names, as one x-tension can require several metacommands, thus the name does not include the prefix "!x-"), whose version string is 3 digits.

Requirements for a relay:

  • The support of this metacommand is mandatory for an ORG relay.
  • It is also required that the list of packages in the !x-orgversions reply includes the package "ORG" and the exact list of supported optional x-tensions.

Requirements for a controlling device: None.

ORG RLVR fixes

Marine Kelley's specification for RLVR protocol gives too much room for interpretation and incompatibilities between devices however supposed to be compliant. This is why in this section we add further requirements for RLVR+ORG devices.

Preliminaries/Reminders

Here we establish some notations related to RLVR protocol.

Here is the RLVR device message grammar (as it already is, nothing new):

<r_msg> ::= IDENT','KEY','<command>','ACK;
<d_msg> ::= IDENT','KEY','<commands>;
<commands> ::= <command> | <command>'|'<commands>;
<command> ::= <rlvcommand> | <metacommand>;
<rlvcommand> ::= '@'RLVCOMMAND;
<metacommand> ::= '!'METACOMMANDNAME<metacommandarguments>;
<metacommandarguments> ::=  | '/'ARG<metacommandarguments>;

where the following tokens were used:

IDENT: any string without ","
KEY: any UUID
ACK: any string without ","
RLVCOMMAND: any string without ","
METACOMMANDNAME: any string without "/" and ","
ARG: any string without "/" and ","

Furthermore we give the following definitions:

  • A controlling device is always considered to be "reachable" if it is within shout range of the relay, as long it does not fail to answer a ping request from the relay. A controlling device is usually considered to be "unreachable" if it is out of shout range of the relay, but x-tensions such as !x-email or proprietary enhancements may modify the notion of "unreachability".
  • The following actions are considered locking a relay:
  • a restricting command followed by a "ok" acknowledgement
  • a ping/pong exchange with this relay
  • The following actions are considered unlocking a relay:
  • the controlling device becoming unreachable.
  • the relay sends "release,KEY,!release,ok"
  • the controlling device sends a !release
  • A relay is locked by a controller if their last interaction of the above types was locking.

General Relay requirements

  • A relay MUST provide a mechanism for checking that every controlling device is reachable, and releasing it if it is not. It is not specified whether this checking process should be automatic or manually triggered.
  • A relay MUST NOT send anything on RLVR channel that is not a valid <r_msg>.
  • A relay MUST ignore any message on RLVR channel that is not a ","-list of 3 items and whose second item is not the key of the avatar wearing the relay.
  • When the relay receives a message meeting the above conditions, considering the 3rd item as a "|"-list of <command>s, then for every <command>:
  • if the <command> is a <rlvcommand>, the relay MUST acknowledge it, either by "ok", and transmit the command as such to the viewer with llOwnerSay("@"+RLVCOMMAND), or by "ko" and not transmit it.
  • if the <command> is a <metacommand>
  • if the METACOMMANDNAME is !pong, no acknowledgement is expected. The relay MUST reinstate all stored restrictions belonging to the controlling device if they weren't already active.
  • if the METACOMMANDNAME is unknown or is not provided with enough arguments for at least one definition of the meta-command, the relay MUST acknowledge by "ko"
  • else if the relay knows the METACOMMANDNAME with at least one definition having less or as many arguments as received in <metacommandarguments>, it MUST acknowledge it by "ok" and choose among possible definitions the one that uses the most arguments. Then if the number of arguments of this definition is n, it MUST execute it using only the n first arguments of <metacommandarguments>, ignoring the trailing arguments if any.
  • if the <command> is neither, then the relay MUST ignore it (no acknowledgement whatsoever)
  • A relay MUST release all restrictions belonging to a controlling device when an unlocking action relative to this device happens (whether if it is just before or just after is irrelevant, as long as the relay does not wait for any further event).
  • A relay MUST never release a restriction outside one of those 2 cases:
  • the controlling device it belongs to specifically asks for the restriction to be released ("@restriction=y", "@clear=blah")
  • an unlocking action relative to the device the restriction belongs to is happening.

General controlling device requirements

  • A controlling device MUST not send anything on RLVR channel that is not a valid <d_msg>.
  • A controlling device MUST, at any time when a relay is locked, provide a mechanism that will unlock it in bounded time. (i.e.: either there is a menu that will release the victim, or there is a timer, or a menu should be able to start such a timer). At least one person MUST know what this mechanism is, and if it requires an action from someone else, be able to tell that other person what s/he has to do.