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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 1 INTERNET-DRAFT PICS 2 MIT/W3C 3 Expires May 21, 1996 November 21, 1995 5 Rating Services and Rating Systems 6 (and Their Machine Readable Descriptions) 8 Status of this Memo 10 This document is an Internet-Draft. Internet-Drafts are working 11 documents of the Internet Engineering Task Force (IETF), its areas, 12 and its working groups. Note that other groups may also distribute 13 working documents as Internet-Drafts. 15 Internet-Drafts are draft documents valid for a maximum of six 16 months and may be updated, replaced, or obsoleted by other documents 17 at any time. It is inappropriate to use Internet-Drafts as 18 reference material or to cite them other than as "work in progress." 20 To learn the current status of any Internet-Draft, please check the 21 "1id-abstracts.txt" listing contained in the Internet-Drafts Shadow 22 Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe), 23 munnari.oz.au (Pacific Rim), ds.internic.net (US East Coast), or 24 ftp.isi.edu (US West Coast). 26 Distribution of this document is unlimited. 28 Comments on this draft should be sent to 29 "pics-spec-comments@w3.org". 31 1. Introduction 33 This document, which has been prepared for the technical 34 subcommittee of PICS (Platform for Internet Content Selection), 35 defines a language for describing rating services. Software 36 programs will read service descriptions written in this language, 37 in order to interpret content labels and assist end-users in 38 configuring selection software. 40 A related document, "Label Syntax and Communication Protocols", 41 , specifies the syntax and semantics 42 of content labels and protocol(s) for distributing labels. 44 The goal of the PICS effort is to enable a marketplace in which many 45 different products and services will be developed, tested, and 46 compared. Hence, the following considerations have had significant 47 impact on this document: 49 o Some organizations may rate items on well-known dimensions, 50 using their own techniques and viewpoints to determine actual 51 ratings. Other organizations may choose to develop their own 52 dimensions for rating. This motivates the distinction between 53 a _rating system_ and a _rating service_ (see the glossary). 54 o Some services may provide access to their ratings on-line, from 55 an HTTP server, while others may either ship them in batches or 56 transmit them on floppy disks or CD-ROMs. 58 2. What is a "Rating Service"? 60 A _rating service_ is an individual, group, organization, or company 61 that provides content labels for information on the Internet. The 62 labels it provides are based on a rating _system_ (see below). Each 63 rating service must describe itself using a newly created MIME type, 64 "application/pics-service". Selection software that relies on 65 ratings from a PICS rating service can first load the 66 "application/pics-service" description. This description allows the 67 software to tailor its user interface to reflect the details of a 68 particular rating service, rather than providing a "one design fits 69 all rating services" interface. 71 This specification does not state how the "application/pics-service" 72 description of a rating service is initially located. For users of 73 the World Wide Web, we expect that well-known sites will provide 74 lists of rating services along with their "application/pics-service" 75 descriptions. It is expected that client programs will cache copies 76 of "application/pics-service" descriptions, so any incompatible 77 change in a service description should be accomplished by creating 78 an entirely new service. 80 Each rating service picks a URL as its unique identifier. It is 81 included in content labels the service produces, to identify their 82 source. To ensure that no other service uses the same identifier, 83 it must be a valid URL. The document available at that URL may be 84 in any format, but we recommend that it: 86 o be an HTML document organized for ease of use by novice 87 computer users (the "application/pics-service" description 88 would be a poor choice); 89 o describe the rating system used, or provide a link to another 90 document describing it; 91 o be available in multiple languages, either through existing 92 negotiation mechanism or through links to alternate language 93 versions. 95 3. What is a "Rating System"? 97 A rating _system_ specifies the dimensions used for labeling, the 98 scale of allowable values on each dimension, and a description of 99 the criteria used in assigning values. For example, the MPAA rates 100 movies in the USA based on a single dimension with allowable values 101 G, PG, PG-13, etc. 103 Each rating system is identified by a valid URL. This enables 104 several services to use the same rating system and refer to it by 105 its identifier. The URL naming a rating system can be accessed to 106 obtain a human-readable description of the rating system. The 107 format of that description is not specified. 109 4. What is a "Content Label"? 111 A _content label_ (or _rating_) contains information about a 112 document. As described in [1], "Label Syntax and Communication 113 Protocols", a content label (or rating) has three parts: 115 1. the URL naming the rating service that produced the label; 116 2. a set of PICS-defined (and extensible) attribute-value pairs, 117 which provide information about the rating such as the date 118 that the rating was assigned; 119 3. a set of rating-system-defined attribute-value pairs, which 120 actually rate the item along various _dimensions_ (also called 121 _categories_). 123 5. The "application/pics-service" Document Type 125 A rating service is defined by a document of type 126 "application/pics-service". The detailed syntax and semantics are 127 presented in the next two sections. Here is an example of such a 128 document, intended only to illustrate the full set of features of a 129 machine description: 131 ((PICS-version 1.0) 132 (rating-system "http://www.gcf.org/ratings") 133 (rating-service "http://www.gcf.org/v1.0/") 134 (icon "icons/gcf.gif") 135 (name "The Good Clean Fun Rating System") 136 (description "Everything you ever wanted to know about soap, 137 cleaners, and related products. For demonstration purposes only.") 139 (category 140 (transmit-as "suds") 141 (name "Soapsuds Index") 142 (min 0.0) 143 (max 1.0)) 145 (category 146 (transmit-as "density") 147 (name "suds density") 148 (label (name "none") (value 0) (icon "icons/none.gif")) 149 (label (name "lots") (value 1) (icon "icons/lots.gif"))) 151 (category 152 (transmit-as "subject") 153 (name "document subject") 154 (multivalue true) 155 (label (name "soap") (value 0)) 156 (label (name "water") (value 1)) 157 (label (name "soapdish") (value 2)) 158 (label-only)) 160 (category 161 (transmit-as "color") 162 (name "picture color") 163 (integer) 165 (category 166 (transmit-as "hue") 167 (label (name "blue") (value 0)) 168 (label (name "red") (value 1)) 169 (label (name "green") (value 2))) 171 (category 172 (transmit-as "intensity") 173 (min 0) 174 (max 255)))) 176 6. Explanation of Sample Rating Service 178 1. The identifier of the rating system used is 179 "http://www.gcf.org/ratings". The document available at that URL 180 should be a human-readable description of the categories, scales, 181 and intended criteria for assigning ratings. 182 2. The identifier of the rating service is 183 "http://www.gcf.org/v1.0/". The labels themselves will have this 184 URL in them to identify the service that created them. The 185 document available at this URL should be a human-readable 186 description of the rating service. 187 3. There is an icon associated with the rating service, and it can 188 be retrieved from "http://www.gcf.org/icons/gcf.gif" (formed by 189 interpreting the _icon_ attribute's value relative to the 190 _rating-service_ identifier). 191 4. There are four top-level categories in this rating system. Each 192 category has a short transmission name to be used in labels; some 193 also have longer names that are more easily understood. For 194 example, the first has transmission name "suds" and the longer 195 name "Soapsuds Index". The second has a transmission name of 196 "density" and longer name "suds density". 197 5. The "Soapsuds Index" category is rated on a scale from 0.0 to 198 1.0, inclusive. 199 6. The "suds density" category can have ratings from negative to 200 positive infinity, but there are two values that have names and 201 icons associated with them. The name "none" is the same as 0, 202 and the name "lots" is the same as 1. Icons associated with 203 those names are found at 204 "http://www.gcf.org/ratings/icons/none.gif" and 205 "http://www.gcf.org/ratings/icons/lots.gif" (i.e. they are 206 dereferenced relative to the _rating-system_ identifier). 207 7. The "document subject" category only allows the values 0, 1, and 208 2 to be used, but a single document can have any combination of 209 these values. Each value has a name (0 is "soap," etc.). So one 210 document might not have any rating on this category, while 211 another is both a "soap" and a "soapdish". 212 8. The "picture color" category has two sub-categories. Values on 213 the "picture color" dimension itself are restricted to integers, 214 and will be transmitted as a category named "color." The first 215 sub-category is transmitted as "color/hue" and the second as 216 "color/intensity". Notice that color/hue can take on only 217 integer values (because it inherits the _integer_ attribute of 218 its parent, "color", category), but there are three values with 219 names ("blue", "red", and "green"). The category color/intensity 220 can take on any integer value between 0 and 255 (inclusive). 222 7. Detailed Syntax of "application/pics-service" 224 Notes: 226 1. Whitespace is ignored except in quoted strings. 227 2. The strings in _transmit-as_ are case insensitive. All other 228 strings are case sensitive. 229 3. This BNF grammar overly constrains the format. The optional 230 attribute/value pairs in _ratingservicedescription_, 231 _categorylist_ and _enum_ may occur in any order. 232 4. Additional attributes may be added over time. For experimental 233 purposes, attributes with names beginning "x-" may be added at 234 any time without prior arrangement. Extending the names that are 235 formally part of this specification requires an additional 236 consensus process before adoption. Clients are expected to 237 ignore any attributes they do not understand. 238 5. This specification requires the use of UTF-7 encoding to allow 239 for the inclusion of non-English description strings. Because 240 internationalization is an area still under discussion in the 241 standards community, this choice may well be subject to change in 242 the near future. For those rating systems and services that use 243 only the US-ASCII character set in their descriptive strings, 244 UTF-7 allows direct encoding of the following (printable) 245 characters: a-z, A-Z, 0-9, '(),-./:?!#$%&*;<=>@[]^_`{|} 246 Notice that "+" is *not* included in this set, since it is used 247 by the UTF-7 encoding system. 248 6. It is guaranteed that this and all future versions of the 249 "application/pics-service" MIME type will begin with the 250 _version_ information, changing from 1.0 as specified here to 251 other numbers as the specification is revised. Rating services 252 are encouraged to place a version number in the _rating-service_ 253 URL, and to change to a new URL when an incompatible change must 254 be made to their specification. 256 ratingservicedescription :: 257 '(' _version_ _ratingsystem_ _ratingservice_ 258 [_icondef_] [_name_] [_description_] 259 ['(' 'default' [_min_] [_max_] [_multi_] [_integer_] 260 [_labeled_] ')'] 261 _categorylist_ ')' 262 version :: '(' 'PICS-version' '1.0' ')' 263 ratingsystem :: '(' 'rating-system' _quotedURL_ ')' 264 ratingservice :: '(' 'rating-service' _quotedURL_ ')' 265 quotedURL :: ' " ' URL ' " ' 266 URL is as defined in [4], "RFC 1738". In addition, PICS defines the 267 following new form for referencing Internet Relay Chat (IRC) rooms: 268 URL :: ... | 'irc://' _host_ '/' _alphanum_ 269 (where _host_ is the usual Internet hostname) 270 icondef :: '(' 'icon' _quotedURL_ ')' 271 name :: '(' 'name' _quotedstring_ ')' 272 description :: '(' 'description' _quotedstring_ ')' 273 quotedstring :: ' " ' _UTF-7_ ' " ' 274 UTF-7 :: Characters encoded using UTF-7, with direct coding of 275 US-ASCII set O *except* for the double-quote (decimal 34) which must 276 be encoded to allow for its use as the string delimiter character. 277 See note above. 278 categorylist :: [1*n] 279 '(' 'category' 280 '(' 'transmit-as' _transmitname_ ')' 281 [_icondef_] [_name_] [_description_] [_min_] 282 [_max_] [_multi_] [_integer_] 283 [_labeled_] [_enumlist_] [_categorylist_] 284 ')' 285 transmitname :: ' " ' [1*n]_alphanumpm_ ' " ' 286 alphanumpm :: 'A' | ... | 'Z' | 'a' | ... | 'z' | '+' | '-' 287 min :: '(' 'min' _minnum_ ')' 288 max :: '(' 'max' _maxnum_ ')' 289 minnum :: _number_ | '-INF' 290 maxnum :: _number_ | '+INF' 291 number :: [_sign_]_unsignedint_['.' [_unsignedint_]] 292 sign :: '+' | '-' 293 unsignedint :: [1*n][0-9] 294 multi :: '(' 'multivalue' [_boolean_] ')' 295 boolean :: 't' | 'f' | 'true' | 'false' 296 integer :: '(' 'integer' [_boolean_] ')' 297 labeled :: '(' 'label-only' [_boolean_ ] ')' 298 enumlist :: [1*n]_enum_ 299 enum :: 300 '(' 'label' _name_ [_description_] 301 '(' 'value' _number_ ')' 302 [_icondef_] 303 ')' 305 For reference, the following attributes are currently defined by the 306 above BNF: 308 1. Within a rating service, there are the attributes _category_, 309 _default_, _description_, _icon_, _name_ and _PICS_. 310 2. Within a category, there are the attributes _description_, 311 _icon_, _integer_, _label_, _label-only_, _max_, _min_, 312 _multivalue_, _name_ and _transmit-as_. 313 3. Within a named value, there are the attributes _description_, 314 _icon_, _name_ and _value_. 316 8. Semantics of the "application/pics-service" Description 318 Recall that the MIME type "application/pics-service" is intended to 319 describe a particular rating service in sufficient detail to 320 automatically generate a user interface for configuring content 321 selection software that relies on the rating service. 323 The _quotedURL_ in the _ratingservice_ identifies the service. This 324 identifier is included in all the labels provided by the rating 325 service. Dereferencing the URL yields a human-readable description 326 of the service. If the optional URL for an icon for the rating 327 service is supplied, it is dereferenced relative to the rating 328 service URL. The _name_ of the rating system is intended to be 329 short and human-readable, with the _description_ being a longer 330 description (suitable, perhaps, for a pop-up box). A complete 331 human-readable description is available from the rating service's 332 URL. 334 The _quotedURL_ in the _ratingsystem_ identifies the rating system 335 used by this service. Dereferencing the URL yields a human-readable 336 description of the rating system. All remaining URLs in the 337 "application/pics-service" description are dereferenced relative to 338 the _ratingsystem_ URL, since they describe features of the rating 339 system. The only exception is the rating service's icon, as 340 described above, which is dereferenced relative to the 341 _ratingservice_ URL, so that the service can maintain its own 342 (possibly copyrighted) identity even if it chooses to share a rating 343 system with other services. 345 The machine-readable description also describes the categories used 346 in the rating system. There may be one or more categories for a 347 given rating system. A single document may have a rating on any or 348 all of these categories. Categories can be nested within one 349 another. 351 A category has a "transmission name" which is used in the actual 352 label for a document. Transmission names should be as short as 353 reasonable. They must be unique within a given rating system (i.e. 354 two categories in the same rating system must *not* have the same 355 transmission name). Unlike the name and description strings, 356 transmission names are language-independent. That is, if a rating 357 system is offered in several languages, the transmission names must 358 be the same in all of them. Categories may be nested within one 359 another (as in the case of "color" in the example rating system). 360 In this case, the transmission name is created in the usual way by 361 starting with the outermost category transmission name, adding a "/" 362 and proceeding inward in the nesting. Thus, the example rating 363 system has three categories, and their transmission names are 364 "color", "color/hue", and "color/intensity". In addition to the 365 transmission name, which is required, a category may optionally have 366 an icon and a human-readable description. 368 Icons, if provided, may be of any size. We recommend, however, that 369 icons be as small as possible, since selection software is likely to 370 embed them in displays that include other text and images as well. 371 We also recommend that a rating service's category icons all be the 372 same size. 374 Values in PICS labels may be integers or fractions with no greater 375 range or precision than that provided by IEEE single-precision 376 floating point numbers. The description for each category can 377 specify restrictions on the range of permissible values for certain 378 named attributes. Values may be restricted to have minimum (_min_ 379 attribute, defaults to "-INF") or maximum (_max_ attribute, defaults 380 to "+INF") values. Values can be restricted to integers by giving 381 the attribute _integer_ the value "true" (the default value is 382 "false" if the attribute is omitted, but "true" if it is present 383 with no value specified). Values may be given names by using the 384 _label_ attribute, and may be restricted to having only these named 385 values by setting the attribute _label-only_ to the value "true" 386 (the default value is "false" if the attribute is omitted, but 387 "true" if it is present with no value specified). When a value is 388 given a name, it may optionally have attached an icon and a 389 human-readable description. Finally, a given category may allow 390 more than a single rating for a given document (consider the 391 dimension "sizes available"); this is indicated by setting the 392 attribute _multivalue_ to "true" (default is "false" if the 393 attribute is omitted, but "true" if it is present with no value 394 specified). 396 For rating systems that contain large numbers of categories or 397 deeply nested categories, it is convenient to allow for inheritance 398 of some attribute values. In particular, the attributes of a 399 category _min_, _max_, _multivalue_, _integer_, and _label-only_ are 400 inherited by a category from its parent. These attributes can be 401 given default values for the entire rating service by using the 402 _default_ attributes. This corresponds to value inheritance in 403 object-oriented systems or lexical scoping in programming languages. 405 Note: While it would be nice to restrict the numeric values of 406 ratings to integers, the following examples motivate our 407 decision to permit fractional values. 409 1. The MPAA rating system was changed to interpolate a new 410 category (PG-13) between "PG" and "R". Had their system 411 been encoded with a tightly packed integer scale it would 412 have required rescinding many existing labels when the 413 change occurred. With fractional numbers there is no need 414 (in principle, at least) to renumber. 415 2. It may be desirable to include the cost of an item in a 416 content label. This cost may not be an integral number of 417 currency units (think, for example, of a micropayment 418 system in which charges of small fractions of a cent are 419 permitted). 420 3. Ratings may be generated by statistical means from the 421 responses of many people. Such ratings could be rounded 422 off to an integer before presentation, but this loses much 423 important information. 425 9. Security Considerations 427 Security considerations will be addressed in other documents in this 428 series and in future revisions of this draft. 430 10. Glossary 432 application/pics-service 433 A new MIME data type, defined in this document. 434 application/pics-labels 435 A new MIME data type used to transmit one or more _labels_, 436 defined in [1], "Label Syntax and Communication Protocols". 437 BNF 438 Backus-Naur Form (or Backus Normal Form). A notation for 439 describing a formal syntax, used extensively in describing 440 programming languages and computer-readable data formats. 441 category 442 The part of a rating system which describes a particular 443 criterion used for rating. For example, a rating system might 444 have three categories named "sexual material," "violence," and 445 "vocabulary." Also called a _dimension_. 446 content label 447 A data structure containing information about a given document's 448 contents. Also called a _rating_ or _content rating_. The 449 content label may accompany the document it is about or be 450 available separately. 451 content rating 452 See _content label_. 453 dimension 454 See _category_. 455 HTML 456 HyperText Markup Language. A means of representing _hypertext_ 457 documents. Based on _SGML_. See the [2], "RFC 1866". 458 HTTP 459 HyperText Transfer Protocol. Used for retrieving document 460 contents and/or descriptive header information. 461 hypertext 462 Text, graphics, and other media connected through links. 463 MIME 464 Multimedia Internet Message Extension. A technique for sending 465 arbitrary data through electronic mail on the Internet. See [3], 466 "RFC 1521". 467 PICS 468 Platform for Internet Content Selection, the name for both the 469 suite of specification documents of which this is a part, and 470 for the organization writing the documents. For more 471 information, see the PICS home page at: "http://www.w3.org/PICS". 472 rating 473 See _content label_. 474 label bureau 475 A computer system which supplies, via a computer network, ratings 476 of documents. It may or may not provide the documents 477 themselves. 478 rating server 479 See _label bureau_. 480 rating service 481 An individual or organization that assigns labels according to 482 some rating system, and then distributes them, perhaps via a 483 label bureau or via CD-ROM. 484 rating system 485 A method for rating information. A rating system consists of one 486 or more _categories_. 487 scale 488 The range of permissible values for a category. 489 SGML 490 Standard Generalized Markup Language. See ISO 8879. 491 transmission name 492 (of a _category_) The short name intended for use over a network 493 to refer to the category. This is distinct from the category 494 name in as much as the transmission name must be 495 language-independent, encoded in ASCII, and as short as 496 reasonably possible. Within a single _rating system_ the 497 transmission names of all categories must be distinct. 498 URL 499 Uniform Resource Locator. Described in [4], "RFC 1738". A URL 500 describes the location and means of retrieval for a single 501 document. It consists of three components: the "scheme" 502 (protocol used to retrieve a document, like "http" or "ftp"), a 503 host name, and a hierarchical document name within that host. 504 For example "http://www.w3.org/PICS" is the URL of the PICS home 505 page. The scheme for retrieving it is "http," the host is 506 "www.w3.org" and the name within that host is "PICS". 507 UTF-7 508 An encoding technique that can be used to transmit Unicode over 509 7-bit ASCII transport systems such as Internet electronic mail. 510 See [5], "RFC 1642". 512 11. References 514 [1] PICS, "Label Syntax and Communication Protocols", Internet 515 Draft, "draft-pics-labels-00.txt", 11/21/95. 516 [2] T. Berners-Lee, D. Connolly, "Hypertext Markup Language - 2.0", 517 RFC 1866, 11/03/1995. 518 [3] N. Borenstein, N. Freed, "MIME (Multipurpose Internet Mail 519 Extensions) Part One: Mechanisms for Specifying and Describing 520 the Format of Internet Message Bodies", RFC 1521, 09/23/1993. 521 [4] T. Berners-Lee, L. Masinter, M. McCahill, "Uniform Resource 522 Locators (URLs)", RFC 1738, 12/20/94. 523 [5] D. Goldsmith, M. Davis, "UTF-7 - A Mail-Safe Transformation 524 Format of Unicode", RFC 1642, 7/13/94. 526 12. Acknowledgments 528 Primary authors of this document: 530 Jim Miller, W3C 531 Paul Resnick, AT&T 532 David Singer, IBM 534 Additional contributors: 536 Brenda Baker, AT&T 537 Tim Berners-Lee, W3C 538 Roxana Bradescu, AT&T 539 Daniel W. Connolly, W3C 540 Roy Fielding, W3C 541 Jay Friedland, SurfWatch 542 Wayne Gramlich, Sun 543 Woodson Hobbs, NewView 544 Rohit Khare, W3C 545 Charlie Kim, Apple 546 John C. Klensin, MCI 547 Tim Krauskopf, Spyglass 548 Ann McCurdy, Microsoft 549 Rich Petke, CompuServe 550 Dave Raggett, W3C 551 Bob Schloss, IBM 552 Ray Soular, SafeSurf 553 Jason Thomas, MIT 554 G. Winfield Treese, OpenMarket 555 Richard Wolpert, Providence Systems 557 13. Author's Address 559 PICS Technical Committee 560 World Wide Web Consortium 561 545 Technology Square 562 Cambridge, MA 02139 563 Phone: 617-253-3194 564 EMail: pics-spec-comments@w3.org 566 Appendix A: Good Clean Fun Rating Service 568 One of the simplest possible rating systems uses a single category, 569 "Minimum recommended age." We present the machine description for a 570 fictional service that uses this rating system. 572 ((PICS-version 1.0) 573 (rating-system "http://www.gcf.org/our-system/") 574 (rating-service "http://www.gcf.org/our-service/v1.0/") 575 (name "The Good Clean Fun Rating Service") 576 (description "We estimate the maturity required to view materials 577 on the Internet.") 578 (category (name "Minimum Age") (transmit-as "age") (integer true))) 580 Appendix B: RSAC Rating Service 582 As a specific example of a deployed rating service, encoded using 583 the PICS machine-readable description format, we present the service 584 supplied by the Recreational Software Advisory Council (RSAC). They 585 use their own (copyrighted) rating system, which we include with 586 their permission. The rating system contains three categories: 587 Violence, Nudity/Sex, and Language. Each category is rated on a 588 scale from 0 to 4, with a specific description for each value. 589 Intermediate values are not permitted. The URLs presented here are 590 fictitious, but represent reasonable choices should RSAC choose to 591 deploy their system on-line. 593 ((PICS-version 1.0) 594 (rating-system "http://www.rsac.org/Ratings/Description/") 595 (rating-service "http://www.rsac.org/v1.0") 596 (icon "icons/rsac.gif") 597 (name "The RSAC Ratings Service") 598 (description "The Recreational Software Advisory Council rating 599 service. Based on the work of Dr. Donald F. Roberts of Stanford 600 University, who has studied the effects of media on children for 601 nearly 20 years.") 602 (default (label-only true)) 604 (category 605 (transmit-as "v") 606 (name "Violence") 607 (icon "icons/violence.gif") 608 (label 609 (name "Conflict") 610 (description "Harmless conflict; some damage to objects") 611 (value 0) (icon "icons/zero.gif")) 612 (label 613 (name "Fighting") 614 (description "Creatures injured or killed; damage to objects; 615 fighting") 616 (value 1) (icon "icons/one.gif")) 617 (label 618 (name "Killing") 619 (description "Humans injured or killed with small amount of 620 blood") 621 (value 2) (icon "icons/two.gif")) 622 (label 623 (name "Blood and Gore") 624 (description "Humans injured or killed; blood and gore") 625 (value 3) (icon "icons/three.gif")) 626 (label 627 (name "Wanton Violence") 628 (description "Wanton and gratuitous violence; torture; rape") 629 (value 4) (icon "icons/four.gif"))) 631 (category 632 (transmit-as "s") 633 (name "Nudity/Sex") 634 (icon "icons/sex.gif") 635 (label 636 (name "None") 637 (description "No nudity or revealing attire / Romance; no sex") 638 (value 0) (icon "icons/zero.gif")) 639 (label 640 (name "Revealing Attire") 641 (description "Revealing attire / Passionate kissing") 642 (value 1) (icon "icons/one.gif")) 643 (label 644 (name "Partial Nudity") 645 (description "Partial nudity / Clothed sexual touching") 646 (value 2) (icon "icons/two.gif")) 647 (label 648 (name "Frontal Nudity") 649 (description "Non-sexual frontal nudity / Non-explicit sexual 650 activity") 651 (value 3) (icon "icons/three.gif")) 652 (label 653 (name "Explicit") 654 (description 655 "Provocative frontal nudity / Explicit sexual activity; 656 sex crimes") 657 (value 4) (icon "icons/four.gif"))) 659 (category 660 (transmit-as "l") 661 (description "Language") 662 (icon "icons/language.gif") 663 (label (name "Slang") 664 (description "Inoffensive slang; no profanity") 665 (value 0) (icon "icons/zero.gif")) 666 (label (name "Mild Expletives") 667 (description "Mild expletives") 668 (value 1) (icon "icons/one.gif")) 669 (label (name "Expletives") 670 (description "Expletives; non-sexual anatomical references") 671 (value 2) (icon "icons/two.gif")) 672 (label (name "Obscene Gestures") 673 (description "Strong, vulgar language; obscene gestures") 674 (value 3) (icon "icons/three.gif")) 675 (label (name "Explicit") 676 (description "Crude or explicit sexual references") 677 (value 4) (icon "icons/four.gif")))) 679 Appendix C: SafeSurf Rating System 681 SafeSurf, a parents' organization, has established a rating system 682 that is in use at a large and growing number of sites on the 683 Internet. They have provided a machine-readable version of their 684 system to PICS as a demonstration of a more complex rating system 685 that includes sub-categories as well as a document classification 686 system. The following specification includes a full description of 687 the rating part of the SafeSurf system, with only a small stub to 688 represent the classifications. 690 ((PICS-version 1.0) 691 (rating-system "http://www.safesurf.com/ratings/description/") 692 (rating-service "http://www.safesurf.com/v1.0/") 693 (icon "icons/ss~~.gif") 694 (name "SafeSurf Parents' Organization") 695 (description "The SafeSurf SS~~ Rating Standard. Designed by and 696 for parents to empower each family to make informed decisions 697 concerning accessibility of online content. Copyright 1995. All 698 Rights Reserved.") 700 (category 701 (transmit-as "Adult") 702 (name "Adult Themes with Caution Levels") 703 (category (name "Age Range") (transmit-as "0") 704 (label (value 1) (name "All Ages")) 705 (label (value 2) (name "Older Children")) 706 (label (value 3) (name "Teens")) 707 (label (value 4) (name "Older Teens")) 708 (label (value 5) (name "Adult Supervision Recommended")) 709 (label (value 6) (name "Adults")) 710 (label (value 7) (name "Limited to Adults")) 711 (label (value 8) (name "Adults Only")) 712 (label (value 9) (name "Explicitly for Adults"))) 714 (category (name "Profanity") (transmit-as "1") 715 (label (value 1) (name "Subtle Innuendo") 716 (description "Subtly Implied through the use of Slang")) 717 (label (value 2) (name "Explicit Innuendo") 718 (description "Explicitly implied through the use of Slang")) 719 (label (value 3) (name "Technical Reference") 720 (description 721 "Dictionary, encyclopedic, news, technical references")) 722 (label (value 4) (name "Non-Graphic-Artistic") 723 (description 724 "Limited non-sexual expletives used in a artistic fashion")) 725 (label (value 5) (name "Graphic-Artistic") 726 (description 727 "Non-sexual expletives used in a artistic fashion")) 728 (label (value 6) (name "Graphic") 729 (description "Limited use of expletives and obscene gestures")) 730 (label (value 7) (name "Detailed Graphic") 731 (description "Casual use of expletives and obscene gestures")) 732 (label (value 8) (name "Explicit Vulgarity") 733 (description 734 "Heavy use of vulgar language and obscene gestures")) 735 (label (value 9) (name "Explicit and Crude") 736 (description 737 "Saturated with crude sexual references and gestures"))) 739 (category (name "Heterosexual Themes") (transmit-as "2") 740 (label (value 1) (name "Subtle Innuendo")) 741 (label (value 2) (name "Explicit Innuendo")) 742 (label (value 3) (name "Technical Reference")) 743 (label (value 4) (name "Non-Graphic-Artistic")) 744 (label (value 5) (name "Graphic-Artistic")) 745 (label (value 6) (name "Graphic")) 746 (label (value 7) (name "Detailed Graphic")) 747 (label (value 8) (name "Explicit Vulgarity")) 748 (label (value 9) (name "Explicit and Crude"))) 750 (category (name "Homosexual Themes") (transmit-as "3") 751 (label (name "Subtle Innuendo") (value 1)) 752 (label (value 2) (name "Explicit Innuendo")) 753 (label (value 3) (name "Technical Reference") 754 (description 755 "Dictionary, encyclopedic, news, medical references")) 756 (label (value 4) (name "Non-Graphic-Artistic")) 757 (label (value 5) (name "Graphic-Artistic")) 758 (label (value 6) (name "Graphic")) 759 (label (value 7) (name "Detailed Graphic")) 760 (label (value 8) (name "Inviting Adult Participation")) 761 (label (value 9) 762 (name "Explicitly Inviting Adult Participation"))) 764 (category (name "Nudity") (transmit-as "4") 765 (label (value 1) (name "Subtle Innuendo")) 766 (label (value 2) (name "Explicit Innuendo")) 767 (label (value 3) (name "Technical Reference")) 768 (label (value 4) (name "Non-Graphic-Artistic")) 769 (label (value 5) (name "Graphic-Artistic")) 770 (label (value 6) (name "Graphic")) 771 (label (value 7) (name "Detailed Graphic")) 772 (label (value 8) (name "Explicit Vulgarity")) 773 (label (value 9) (name "Explicit and Crude"))) 775 (category (name "Violence") (transmit-as "5") 776 (label (value 1) (name "Subtle Innuendo")) 777 (label (value 2) (name "Explicit Innuendo")) 778 (label (value 3) (name "Technical Reference")) 779 (label (value 4) (name "Non-Graphic-Artistic")) 780 (label (value 5) (name "Graphic-Artistic")) 781 (label (value 6) (name "Graphic")) 782 (label (value 7) (name "Detailed Graphic")) 783 (label (value 8) 784 (name 785 "Inviting Participation in Graphic Interactive Format")) 786 (label (value 9) 787 (name "Encouraging Personal Participation, Weapon Making"))) 789 (category (name "Sex Violence and Profanity") 790 (transmit-as "6") 791 (label (value 1) (name "Subtle Innuendo")) 792 (label (value 2) (name "Explicit Innuendo")) 793 (label (value 3) (name "Technical Reference")) 794 (label (value 4) (name "Non-Graphic-Artistic")) 795 (label (value 5) (name "Graphic-Artistic")) 796 (label (value 6) (name "Graphic")) 797 (label (value 7) (name "Detailed Graphic")) 798 (label (value 8) (name "Explicit Vulgarity")) 799 (label (value 9) (name "Explicit and Crude"))) 801 (category (name "Bigotry") (transmit-as "7") 802 (label (value 1) (name "Subtle Innuendo")) 803 (label (value 2) (name "Explicit Innuendo")) 804 (label (value 3) (name "Technical Reference")) 805 (label (value 4) (name "Non-Graphic-Literary")) 806 (label (value 5) (name "Graphic-Literary")) 807 (label (value 6) (name "Graphic Discussions")) 808 (label (value 7) (name "Endorsing Hatred")) 809 (label (value 8) 810 (name "Endorsing Violent or Hateful Action")) 811 (label (value 9) 812 (name "Advocating Violent or Hateful Action"))) 814 (category (name "Glorifying Drug Use") 815 (transmit-as "8") 816 (label (value 1) (name "Subtle Innuendo")) 817 (label (value 2) (name "Explicit Innuendo")) 818 (label (value 3) (name "Technical Reference")) 819 (label (value 4) (name "Non-Graphic-Artistic")) 820 (label (value 5) (name "Graphic-Artistic")) 821 (label (value 6) (name "Graphic")) 822 (label (value 7) (name "Detailed Graphic")) 823 (label (value 8) 824 (name "Simulated Interactive Participation")) 825 (label (value 9) 826 (name "Soliciting Personal Participation"))) 828 (category (name "Other Adult Themes") (transmit-as "9") 829 (label (value 1) (name "Subtle Innuendo")) 830 (label (value 2) (name "Explicit Innuendo")) 831 (label (value 3) (name "Technical Reference")) 832 (label (value 4) (name "Non-Graphic-Artistic")) 833 (label (value 5) (name "Graphic-Artistic")) 834 (label (value 6) (name "Graphic")) 835 (label (value 7) (name "Detailed Graphic")) 836 (label (value 8) (name "Explicit Vulgarity")) 837 (label (value 9) (name "Explicit and Crude"))) 839 (category (name "Gambling") (transmit-as "A") 840 (label (value 1) (name "Subtle Innuendo")) 841 (label (value 2) (name "Explicit Innuendo")) 842 (label (value 3) (name "Technical Discussion")) 843 (label (value 4) (name "Non-Graphic-Artistic, Advertising")) 844 (label (value 5) (name "Graphic-Artistic, Advertising")) 845 (label (value 6) (name "Simulated Gambling")) 846 (label (value 7) (name "Real Life Gambling without Stakes")) 847 (label (value 8) 848 (name 849 "Encouraging Interactive Real Life Participation with Stakes")) 850 (label (value 9) (name "Providing Means with Stakes")))) 852 (category (name "Classification with Percentage") 853 (transmit-as "Class") (min 1) (max 100) (integer true) 854 (category (transmit-as "00") (name "General Information")))) 856 This Internet Draft Expires on May 21, 1996