diff --git a/library/network/protocol/content_negotation/src/character_encoding_variant_results.e b/library/network/protocol/content_negotation/src/character_encoding_variant_results.e
deleted file mode 100644
index 5fd5ab24..00000000
--- a/library/network/protocol/content_negotation/src/character_encoding_variant_results.e
+++ /dev/null
@@ -1,58 +0,0 @@
-note
-	description: "Summary description for {CHARACTER_ENCODING_VARIANT_RESULTS}."
-	author: ""
-	date: "$Date$"
-	revision: "$Revision$"
-
-class
-	CHARACTER_ENCODING_VARIANT_RESULTS
-
-feature -- Access
-
-	character_type: detachable STRING
-
-	variant_header: detachable STRING
-
-	supported_variants: detachable LIST [STRING]
-
-	is_acceptable: BOOLEAN
-
-feature -- Change Element
-
-	set_character_type (a_character_type: STRING)
-			-- Set `character_type' with `a_character_type'
-		do
-			character_type := a_character_type
-		ensure
-			character_type_set: character_type /= Void implies a_character_type = character_type
-		end
-
-	set_variant_header
-			-- Set variant header as `Accept-Charset'
-		do
-			variant_header := "Accept-Charset"
-		ensure
-			variant_header_set: attached variant_header as l_variant_header implies l_variant_header.same_string ("Accept-Charset")
-		end
-
-	set_supported_variants (a_supported: LIST [STRING])
-			-- Set `supported_variants' with `a_supported'
-		do
-			supported_variants := a_supported
-		ensure
-			supported_variants_set: supported_variants /= Void implies supported_variants = a_supported
-		end
-
-	set_acceptable (acceptable: BOOLEAN)
-			-- Set `is_acceptable' with `acceptabe'
-		do
-			is_acceptable := acceptable
-		ensure
-			is_acceptable_set: is_acceptable = acceptable
-		end
-
-note
-	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
-	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
-
-end
diff --git a/library/network/protocol/content_negotation/src/compression_variant_results.e b/library/network/protocol/content_negotation/src/compression_variant_results.e
deleted file mode 100644
index 8309c19e..00000000
--- a/library/network/protocol/content_negotation/src/compression_variant_results.e
+++ /dev/null
@@ -1,59 +0,0 @@
-note
-	description: "Summary description for {COMPRESSION_VARIANT_RESULTS}."
-	author: ""
-	date: "$Date$"
-	revision: "$Revision$"
-	EIS: "name= Compression", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3", "protocol=uri"
-
-class
-	COMPRESSION_VARIANT_RESULTS
-
-feature -- Access
-
-	compression_type: detachable STRING
-
-	variant_header: detachable STRING
-
-	supported_variants: detachable LIST [STRING]
-
-	is_acceptable: BOOLEAN
-
-feature -- Change Element
-
-	set_compression_type (a_compression_type: STRING)
-			-- Set `compression_type' with `a_compression_type'
-		do
-			compression_type := a_compression_type
-		ensure
-			compression_type_set: compression_type /= Void implies a_compression_type = compression_type
-		end
-
-	set_variant_header
-			-- Set variant_header as `Accept-Encoding'
-		do
-			variant_header := "Accept-Encoding"
-		ensure
-			variant_header_set: attached variant_header as l_variant_header implies l_variant_header.same_string ("Accept-Encoding")
-		end
-
-	set_supported_variants (a_supported: LIST [STRING])
-			-- Set `supported_variants' with `a_supported'
-		do
-			supported_variants := a_supported
-		ensure
-			supported_variants_set: supported_variants /= Void implies supported_variants = a_supported
-		end
-
-	set_acceptable (acceptable: BOOLEAN)
-			-- Set `is_acceptable' with `acceptable'
-		do
-			is_acceptable := acceptable
-		ensure
-			is_acceptable_set: is_acceptable = acceptable
-		end
-
-note
-	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
-	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
-
-end
diff --git a/library/network/protocol/content_negotation/src/conneg_server_side.e b/library/network/protocol/content_negotation/src/conneg_server_side.e
index f13513c8..b1fea0db 100644
--- a/library/network/protocol/content_negotation/src/conneg_server_side.e
+++ b/library/network/protocol/content_negotation/src/conneg_server_side.e
@@ -28,7 +28,7 @@ create
 
 feature -- Initialization
 
-	make (a_mime: STRING; a_language: STRING; a_charset: STRING; a_encoding: STRING)
+	make (a_mime: READABLE_STRING_8; a_language: READABLE_STRING_8; a_charset: READABLE_STRING_8; a_encoding: READABLE_STRING_8)
 		do
 			set_mime_default (a_mime)
 			set_language_default (a_language)
@@ -43,29 +43,21 @@ feature -- Initialization
 
 feature -- AccessServer Side Defaults Formats
 
-	mime_default: STRING
+	mime_default: READABLE_STRING_8
+			-- Media types which are acceptable for the response
 
+	language_default: READABLE_STRING_8
+			-- Set of natural languages that are preferred as a response to the request
 
+	charset_default: READABLE_STRING_8
+			-- Character sets are acceptable for the response.
 
-	language_default: STRING
-
-
-
-	charset_default: STRING
-
-
-	encoding_default: STRING
-
-	set_encoding_defautl (an_encoding: STRING)
-		do
-			encoding_default := an_encoding
-		ensure
-			set_encoding: an_encoding ~ encoding_default
-		end
+	encoding_default: READABLE_STRING_8
+			--  Content-codings  that are acceptable in the response.
 
 feature -- Change Element
 
-	set_mime_default (a_mime: STRING)
+	set_mime_default (a_mime: READABLE_STRING_8)
 			-- set the mime_default with `a_mime'
 		do
 			mime_default := a_mime
@@ -73,7 +65,7 @@ feature -- Change Element
 			set_mime_default: a_mime = mime_default
 		end
 
-	set_language_default (a_language: STRING)
+	set_language_default (a_language: READABLE_STRING_8)
 			-- set the language_default with `a_language'
 		do
 			language_default := a_language
@@ -81,7 +73,7 @@ feature -- Change Element
 			set_language: a_language = language_default
 		end
 
-	set_charset_default (a_charset: STRING)
+	set_charset_default (a_charset: READABLE_STRING_8)
 			-- set the charset_default with `a_charset'
 		do
 			charset_default := a_charset
@@ -89,7 +81,7 @@ feature -- Change Element
 			set_charset: a_charset = charset_default
 		end
 
-	set_encoding_default (a_encoding: STRING)
+	set_encoding_default (a_encoding: READABLE_STRING_8)
 		do
 			encoding_default := a_encoding
 		ensure
@@ -100,31 +92,31 @@ feature -- Change Element
 
 feature -- Media Type Negotiation
 
-	media_type_preference (mime_types_supported: LIST [STRING]; header: detachable READABLE_STRING_8): MEDIA_TYPE_VARIANT_RESULTS
-			-- mime_types_supported represent media types supported by the server.
-			-- header represent the Accept header, ie, the client preferences.
+	media_type_preference (a_mime_types_supported: LIST [READABLE_STRING_8]; a_header: detachable READABLE_STRING_8): MEDIA_TYPE_VARIANT_RESULTS
+			-- `a_mime_types_supported' represent media types supported by the server.
+			-- `a_header represent' the Accept header, ie, the client preferences.
 			-- Return which media type to use for representaion in a response, if the server support
 			-- one media type, or empty in other case.
 		note
 			EIS: "name=media type", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.1", "protocol=uri"
 		local
-			mime_match: STRING
+			l_mime_match: READABLE_STRING_8
 		do
 			create Result
-			if header = Void or else header.is_empty then
+			if a_header = Void or else a_header.is_empty then
 					-- the request has no Accept header, ie the header is empty, in this case we use the default format
 				Result.set_acceptable (TRUE)
 				Result.set_media_type (mime_default)
 			else
 					-- select the best match, server support, client preferences
-				mime_match := mime.best_match (mime_types_supported, header)
-				if mime_match.is_empty then
+				l_mime_match := mime.best_match (a_mime_types_supported, a_header)
+				if l_mime_match.is_empty then
 						-- The server does not support any of the media types prefered by the client
 					Result.set_acceptable (False)
-					Result.set_supported_variants (mime_types_supported)
+					Result.set_supported_variants (a_mime_types_supported)
 				else
 						-- Set the best match
-					Result.set_media_type (mime_match)
+					Result.set_media_type (l_mime_match)
 					Result.set_acceptable (True)
 					Result.set_variant_header
 				end
@@ -133,32 +125,32 @@ feature -- Media Type Negotiation
 
 feature -- Encoding Negotiation
 
-	charset_preference (server_charset_supported: LIST [STRING]; header: detachable READABLE_STRING_8): CHARACTER_ENCODING_VARIANT_RESULTS
-			-- server_charset_supported represent a list of charset supported by the server.
-			-- header represent the Accept-Charset header, ie, the client preferences.
+	charset_preference (a_server_charset_supported: LIST [READABLE_STRING_8]; a_header: detachable READABLE_STRING_8): CHARACTER_ENCODING_VARIANT_RESULTS
+			-- `a_server_charset_supported' represent a list of charset supported by the server.
+			-- `a_header' represent the Accept-Charset header, ie, the client preferences.
 			-- Return which Charset to use in a response, if the server support
 			-- one Charset, or empty in other case.
 		note
 			EIS: "name=charset", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.2", "protocol=uri"
 		local
-			charset_match: STRING
+			l_charset_match: READABLE_STRING_8
 		do
 			create Result
-			if header = Void or else header.is_empty then
+			if a_header = Void or else a_header.is_empty then
 					-- the request has no Accept-Charset header, ie the header is empty, in this case use default charset encoding
 					-- (UTF-8)
 				Result.set_acceptable (TRUE)
 				Result.set_character_type (charset_default)
 			else
 					-- select the best match, server support, client preferences
-				charset_match := common.best_match (server_charset_supported, header)
-				if charset_match.is_empty then
+				l_charset_match := common.best_match (a_server_charset_supported, a_header)
+				if l_charset_match.is_empty then
 						-- The server does not support any of the compression types prefered by the client
 					Result.set_acceptable (False)
-					Result.set_supported_variants (server_charset_supported)
+					Result.set_supported_variants (a_server_charset_supported)
 				else
 						-- Set the best match
-					Result.set_character_type (charset_match)
+					Result.set_character_type (l_charset_match)
 					Result.set_acceptable (True)
 					Result.set_variant_header
 				end
@@ -167,31 +159,31 @@ feature -- Encoding Negotiation
 
 feature -- Compression Negotiation
 
-	encoding_preference (server_encoding_supported: LIST [STRING]; header: detachable READABLE_STRING_8): COMPRESSION_VARIANT_RESULTS
-			-- server_encoding_supported represent a list of encoding supported by the server.
-			-- header represent the Accept-Encoding header, ie, the client preferences.
+	encoding_preference (a_server_encoding_supported: LIST [READABLE_STRING_8]; a_header: detachable READABLE_STRING_8): COMPRESSION_VARIANT_RESULTS
+			-- `a_server_encoding_supported' represent a list of encoding supported by the server.
+			-- `a_header' represent the Accept-Encoding header, ie, the client preferences.
 			-- Return which Encoding to use in a response, if the server support
 			-- one Encoding, or empty in other case.
 		note
 			EIS: "name=encoding", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3", "protocol=uri"
 		local
-			compression_match: STRING
+			l_compression_match: READABLE_STRING_8
 		do
 			create Result
-			if header = Void or else header.is_empty then
+			if a_header = Void or else a_header.is_empty then
 					-- the request has no Accept-Encoding header, ie the header is empty, in this case do not compress representations
 				Result.set_acceptable (TRUE)
 				Result.set_compression_type (encoding_default)
 			else
 					-- select the best match, server support, client preferences
-				compression_match := common.best_match (server_encoding_supported, header)
-				if compression_match.is_empty then
+				l_compression_match := common.best_match (a_server_encoding_supported, a_header)
+				if l_compression_match.is_empty then
 						-- The server does not support any of the compression types prefered by the client
 					Result.set_acceptable (False)
-					Result.set_supported_variants (server_encoding_supported)
+					Result.set_supported_variants (a_server_encoding_supported)
 				else
 						-- Set the best match
-					Result.set_compression_type (compression_match)
+					Result.set_compression_type (l_compression_match)
 					Result.set_acceptable (True)
 					Result.set_variant_header
 				end
@@ -200,32 +192,32 @@ feature -- Compression Negotiation
 
 feature -- Language Negotiation
 
-	language_preference (server_language_supported: LIST [STRING]; header: detachable READABLE_STRING_8): LANGUAGE_VARIANT_RESULTS
-			-- server_language_supported represent a list of languages supported by the server.
-			-- header represent the Accept-Language header, ie, the client preferences.
+	language_preference (a_server_language_supported: LIST [READABLE_STRING_8]; a_header: detachable READABLE_STRING_8): LANGUAGE_VARIANT_RESULTS
+			-- `a_server_language_supported' represent a list of languages supported by the server.
+			-- `a_header' represent the Accept-Language header, ie, the client preferences.
 			-- Return which Language to use in a response, if the server support
 			-- one Language, or empty in other case.
 		note
 			EIS: "name=language", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.4", "protocol=uri"
 
 		local
-			language_match: STRING
+			l_language_match: READABLE_STRING_8
 		do
 			create Result
-			if header = Void or else header.is_empty then
+			if a_header = Void or else a_header.is_empty then
 					-- the request has no Accept header, ie the header is empty, in this case we use the default format
 				Result.set_acceptable (TRUE)
 				Result.set_language_type (language_default)
 			else
 					-- select the best match, server support, client preferences
-				language_match := language.best_match (server_language_supported, header)
-				if language_match.is_empty then
+				l_language_match := language.best_match (a_server_language_supported, a_header)
+				if l_language_match.is_empty then
 						-- The server does not support any of the media types prefered by the client
 					Result.set_acceptable (False)
-					Result.set_supported_variants (server_language_supported)
+					Result.set_supported_variants (a_server_language_supported)
 				else
 						-- Set the best match
-					Result.set_language_type (language_match)
+					Result.set_language_type (l_language_match)
 					Result.set_acceptable (True)
 					Result.set_variant_header
 				end
diff --git a/library/network/protocol/content_negotation/src/language_variant_results.e b/library/network/protocol/content_negotation/src/language_variant_results.e
deleted file mode 100644
index c904402a..00000000
--- a/library/network/protocol/content_negotation/src/language_variant_results.e
+++ /dev/null
@@ -1,63 +0,0 @@
-note
-	description: "Summary description for {LANGUAGE_VARIANT_RESULTS}."
-	author: ""
-	date: "$Date$"
-	revision: "$Revision$"
-
-class
-	LANGUAGE_VARIANT_RESULTS
-
-feature -- Access
-
-	language_type: detachable STRING
-
-
-	variant_header: detachable STRING
-
-
-	supported_variants: detachable LIST [STRING]
-
-
-	is_acceptable: BOOLEAN
-
-
-feature -- Change Element
-
-	set_acceptable (acceptable: BOOLEAN)
-			-- Set `is_acceptable' with `acceptable'
-		do
-			is_acceptable := acceptable
-		ensure
-			is_acceptable_set: is_acceptable = acceptable
-		end
-
-	set_language_type (a_language_type: STRING)
-			-- Set `language_type' with `a_language_type'
-		do
-			language_type := a_language_type
-		ensure
-			language_type_set: language_type/= Void implies a_language_type = language_type
-		end
-
-	set_variant_header
-			-- Set variant header as 'Accept-Language'
-		do
-			variant_header := "Accept-Language"
-		ensure
-			variant_header_set: attached variant_header as l_variant_header implies l_variant_header.same_string ("Accept-Language")
-		end
-
-	set_supported_variants (a_supported: LIST [STRING])
-			-- Set `supported vairants' with `a_supported'
-		do
-			supported_variants := a_supported
-		ensure
-			set_supported_variants: supported_variants /= Void implies supported_variants = a_supported
-		end
-
-
-note
-	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
-	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
-
-end
diff --git a/library/network/protocol/content_negotation/src/media_type_variant_results.e b/library/network/protocol/content_negotation/src/media_type_variant_results.e
deleted file mode 100644
index a73ace00..00000000
--- a/library/network/protocol/content_negotation/src/media_type_variant_results.e
+++ /dev/null
@@ -1,62 +0,0 @@
-note
-	description: "Summary description for {MEDIA_TYPE_VARIANT_RESULTS}."
-	author: ""
-	date: "$Date$"
-	revision: "$Revision$"
-
-class
-	MEDIA_TYPE_VARIANT_RESULTS
-
-feature -- Access
-
-	media_type: detachable STRING
-
-	variant_header: detachable STRING
-
-	supported_variants: detachable LIST [STRING]
-
-	is_acceptable: BOOLEAN
-
-
-feature -- Change Element
-
-	set_media_type (a_media_type: STRING)
-			-- Set `media_type' as `a_media_type'
-		do
-			media_type := a_media_type
-		ensure
-			media_type_set: media_type /= Void implies media_type = a_media_type
-		end
-
-
-	set_variant_header
-			-- Set variant header as `Accept'
-		do
-			variant_header := "Accept"
-		ensure
-			variant_header_set: attached variant_header as l_variant_header implies l_variant_header.same_string ("Accept")
-		end
-
-
-	set_supported_variants (a_supported: LIST [STRING])
-			-- Set `supported_variants' with `a_supported'
-		do
-			supported_variants := a_supported
-		ensure
-			supported_variants_variants: supported_variants /= Void implies supported_variants = a_supported
-		end
-
-
-	set_acceptable (acceptable: BOOLEAN)
-			-- Set `is_acceptable' with `acceptable'
-		do
-			is_acceptable := acceptable
-		ensure
-			is_acceptable_set: is_acceptable = acceptable
-		end
-
-note
-	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
-	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
-
-end
diff --git a/library/network/protocol/content_negotation/src/common_accept_header_parser.e b/library/network/protocol/content_negotation/src/parsers/common_accept_header_parser.e
similarity index 86%
rename from library/network/protocol/content_negotation/src/common_accept_header_parser.e
rename to library/network/protocol/content_negotation/src/parsers/common_accept_header_parser.e
index 75aefb55..444ddfcf 100644
--- a/library/network/protocol/content_negotation/src/common_accept_header_parser.e
+++ b/library/network/protocol/content_negotation/src/parsers/common_accept_header_parser.e
@@ -9,19 +9,24 @@ note
 class
 	COMMON_ACCEPT_HEADER_PARSER
 
+inherit {NONE}
+
+	STRING_UTILS
+
+
 feature -- Parser
 
-	parse_common (header: STRING): COMMON_RESULTS
+	parse_common (header: READABLE_STRING_8): COMMON_RESULTS
 			-- Parses `header' charset/encoding into its component parts.
 			-- For example, the charset 'iso-8889-5' would get parsed
 			-- into:
 			-- ('iso-8889-5', {'q':'1.0'})
 		local
-			l_parts: LIST [STRING]
-			sub_parts: LIST [STRING]
-			p: STRING
+			l_parts: LIST [READABLE_STRING_8]
+			sub_parts: LIST [READABLE_STRING_8]
+			p: READABLE_STRING_8
 			i: INTEGER
-			l_header: STRING
+			l_header: READABLE_STRING_8
 		do
 			create Result.make
 			l_parts := header.split (';')
@@ -45,7 +50,7 @@ feature -- Parser
 			Result.set_field (trim (l_header))
 		end
 
-	fitness_and_quality_parsed (a_field: STRING; parsed_charsets: LIST [COMMON_RESULTS]): FITNESS_AND_QUALITY
+	fitness_and_quality_parsed (a_field: READABLE_STRING_8; parsed_charsets: LIST [COMMON_RESULTS]): FITNESS_AND_QUALITY
 			-- Find the best match for a given charset/encoding against a list of charsets/encodings
 			-- that have already been parsed by parse_common. Returns a
 			-- tuple of the fitness value and the value of the 'q' quality parameter of
@@ -57,7 +62,7 @@ feature -- Parser
 			best_fit_q: REAL_64
 			target: COMMON_RESULTS
 			range: COMMON_RESULTS
-			element: detachable STRING
+			element: detachable READABLE_STRING_8
 			l_fitness: INTEGER
 		do
 			best_fitness := -1
@@ -104,7 +109,7 @@ feature -- Parser
 			create Result.make (best_fitness, best_fit_q)
 		end
 
-	quality_parsed (a_field: STRING; parsed_common: LIST [COMMON_RESULTS]): REAL_64
+	quality_parsed (a_field: READABLE_STRING_8; parsed_common: LIST [COMMON_RESULTS]): REAL_64
 			--	Find the best match for a given charset/encoding against a list of charsets/encodings that
 			--	have already been parsed by parse_charsets(). Returns the 'q' quality
 			--	parameter of the best match, 0 if no match was found. This function
@@ -113,11 +118,11 @@ feature -- Parser
 			Result := fitness_and_quality_parsed (a_field, parsed_common).quality
 		end
 
-	quality (a_field: STRING; commons: STRING): REAL_64
+	quality (a_field: READABLE_STRING_8; commons: READABLE_STRING_8): REAL_64
 			-- Returns the quality 'q' of a charset/encoding when compared against the
 			-- a list of charsets/encodings/
 		local
-			l_commons: LIST [STRING]
+			l_commons: LIST [READABLE_STRING_8]
 			res: ARRAYED_LIST [COMMON_RESULTS]
 			p_res: COMMON_RESULTS
 		do
@@ -135,12 +140,12 @@ feature -- Parser
 			Result := quality_parsed (a_field, res)
 		end
 
-	best_match (supported: LIST [STRING]; header: STRING): STRING
+	best_match (supported: LIST [READABLE_STRING_8]; header: READABLE_STRING_8): READABLE_STRING_8
 			-- Choose the accept with the highest fitness score and quality ('q') from a list of candidates.
 		local
 			l_header_results: LIST [COMMON_RESULTS]
 			weighted_matches: LIST [FITNESS_AND_QUALITY]
-			l_res: LIST [STRING]
+			l_res: LIST [READABLE_STRING_8]
 			p_res: COMMON_RESULTS
 			fitness_and_quality, first_one: detachable FITNESS_AND_QUALITY
 		do
@@ -245,32 +250,6 @@ feature -- Parser
 			end
 		end
 
-feature -- Util
-
-	mime_type (s: STRING): STRING
-		local
-			p: INTEGER
-		do
-			p := s.index_of (';', 1)
-			if p > 0 then
-				Result := trim (s.substring (1, p - 1))
-			else
-				Result := trim (s.string)
-			end
-		end
-
-	trim (a_string: STRING): STRING
-			-- trim whitespace from the beginning and end of a string
-		require
-			valid_argument: a_string /= Void
-		do
-			a_string.left_adjust
-			a_string.right_justify
-			Result := a_string
-		ensure
-			result_same_as_argument: a_string = Result
-		end
-
 note
 	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
 	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
diff --git a/library/network/protocol/content_negotation/src/fitness_and_quality.e b/library/network/protocol/content_negotation/src/parsers/fitness_and_quality.e
similarity index 100%
rename from library/network/protocol/content_negotation/src/fitness_and_quality.e
rename to library/network/protocol/content_negotation/src/parsers/fitness_and_quality.e
diff --git a/library/network/protocol/content_negotation/src/language_parse.e b/library/network/protocol/content_negotation/src/parsers/language_parse.e
similarity index 87%
rename from library/network/protocol/content_negotation/src/language_parse.e
rename to library/network/protocol/content_negotation/src/parsers/language_parse.e
index 476400c7..9d4cab18 100644
--- a/library/network/protocol/content_negotation/src/language_parse.e
+++ b/library/network/protocol/content_negotation/src/parsers/language_parse.e
@@ -8,24 +8,26 @@ note
 class
 	LANGUAGE_PARSE
 
-inherit
+inherit {NONE}
+
+	STRING_UTILS
 
 	REFACTORING_HELPER
 
 feature -- Parser
 
-	parse_mime_type (a_mime_type: STRING): LANGUAGE_RESULTS
+	parse_mime_type (a_mime_type: READABLE_STRING_8): LANGUAGE_RESULTS
 			-- Parses a mime-type into its component parts.
 			-- For example, the media range 'application/xhtml;q=0.5' would get parsed
 			-- into:
 			-- ('application', 'xhtml', {'q', '0.5'})
 		local
-			l_parts: LIST [STRING]
-			p: STRING
-			sub_parts: LIST [STRING]
+			l_parts: LIST [READABLE_STRING_8]
+			p: READABLE_STRING_8
+			sub_parts: LIST [READABLE_STRING_8]
 			i: INTEGER
-			l_full_type: STRING
-			l_types: LIST [STRING]
+			l_full_type: READABLE_STRING_8
+			l_types: LIST [READABLE_STRING_8]
 		do
 			fixme ("Improve code!!!")
 			create Result.make
@@ -58,7 +60,7 @@ feature -- Parser
 			end
 		end
 
-	parse_media_range (a_range: STRING): LANGUAGE_RESULTS
+	parse_media_range (a_range: READABLE_STRING_8): LANGUAGE_RESULTS
 			-- Media-ranges are mime-types with wild-cards and a 'q' quality parameter.
 			-- For example, the media range 'application/*;q=0.5' would get parsed into:
 			-- ('application', '*', {'q', '0.5'})
@@ -83,7 +85,7 @@ feature -- Parser
 			end
 		end
 
-	fitness_and_quality_parsed (a_mime_type: STRING; parsed_ranges: LIST [LANGUAGE_RESULTS]): FITNESS_AND_QUALITY
+	fitness_and_quality_parsed (a_mime_type: READABLE_STRING_8; parsed_ranges: LIST [LANGUAGE_RESULTS]): FITNESS_AND_QUALITY
 			-- Find the best match for a given mimeType against a list of media_ranges
 			-- that have already been parsed by parse_media_range. Returns a
 			-- tuple of the fitness value and the value of the 'q' quality parameter of
@@ -95,9 +97,9 @@ feature -- Parser
 			best_fit_q: REAL_64
 			target: LANGUAGE_RESULTS
 			range: LANGUAGE_RESULTS
-			keys: LIST [STRING]
+			keys: LIST [READABLE_STRING_8]
 			param_matches: INTEGER
-			element: detachable STRING
+			element: detachable READABLE_STRING_8
 			l_fitness: INTEGER
 		do
 			best_fitness := -1
@@ -161,7 +163,7 @@ feature -- Parser
 			create Result.make (best_fitness, best_fit_q)
 		end
 
-	quality_parsed (a_mime_type: STRING; parsed_ranges: LIST [LANGUAGE_RESULTS]): REAL_64
+	quality_parsed (a_mime_type: READABLE_STRING_8; parsed_ranges: LIST [LANGUAGE_RESULTS]): REAL_64
 			--	Find the best match for a given mime-type against a list of ranges that
 			--	have already been parsed by parseMediaRange(). Returns the 'q' quality
 			--	parameter of the best match, 0 if no match was found. This function
@@ -171,11 +173,11 @@ feature -- Parser
 			Result := fitness_and_quality_parsed (a_mime_type, parsed_ranges).quality
 		end
 
-	quality (a_mime_type: STRING; ranges: STRING): REAL_64
+	quality (a_mime_type: READABLE_STRING_8; ranges: READABLE_STRING_8): REAL_64
 			-- Returns the quality 'q' of a mime-type when compared against the
 			-- mediaRanges in ranges.
 		local
-			l_ranges: LIST [STRING]
+			l_ranges: LIST [READABLE_STRING_8]
 			res: ARRAYED_LIST [LANGUAGE_RESULTS]
 			p_res: LANGUAGE_RESULTS
 		do
@@ -193,15 +195,15 @@ feature -- Parser
 			Result := quality_parsed (a_mime_type, res)
 		end
 
-	best_match (supported: LIST [STRING]; header: STRING): STRING
+	best_match (supported: LIST [READABLE_STRING_8]; header: READABLE_STRING_8): READABLE_STRING_8
 			-- Choose the mime-type with the highest fitness score and quality ('q') from a list of candidates.
 		local
 			l_header_results: LIST [LANGUAGE_RESULTS]
 			weighted_matches: LIST [FITNESS_AND_QUALITY]
-			l_res: LIST [STRING]
+			l_res: LIST [READABLE_STRING_8]
 			p_res: LANGUAGE_RESULTS
 			fitness_and_quality, first_one: detachable FITNESS_AND_QUALITY
-			s: STRING
+			s: READABLE_STRING_8
 		do
 			l_res := header.split (',')
 			create {ARRAYED_LIST [LANGUAGE_RESULTS]} l_header_results.make (l_res.count)
@@ -299,32 +301,6 @@ feature -- Parser
 			end
 		end
 
-feature {NONE} -- Implementation
-
-	mime_type (s: STRING): STRING
-		local
-			p: INTEGER
-		do
-			p := s.index_of (';', 1)
-			if p > 0 then
-				Result := trim (s.substring (1, p - 1))
-			else
-				Result := trim (s.string)
-			end
-		end
-
-	trim (a_string: STRING): STRING
-			-- trim whitespace from the beginning and end of a string
-		require
-			valid_argument: a_string /= Void
-		do
-			a_string.left_adjust
-			a_string.right_justify
-			Result := a_string
-		ensure
-			result_same_as_argument: a_string = Result
-		end
-
 note
 	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
 	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
diff --git a/library/network/protocol/content_negotation/src/mime_parse.e b/library/network/protocol/content_negotation/src/parsers/mime_parse.e
similarity index 88%
rename from library/network/protocol/content_negotation/src/mime_parse.e
rename to library/network/protocol/content_negotation/src/parsers/mime_parse.e
index 823fe36a..98aaa117 100644
--- a/library/network/protocol/content_negotation/src/mime_parse.e
+++ b/library/network/protocol/content_negotation/src/parsers/mime_parse.e
@@ -7,12 +7,15 @@
 class
 	MIME_PARSE
 
-inherit
+inherit {NONE}
+
+	STRING_UTILS
+
 	REFACTORING_HELPER
 
 feature -- Parser
 
-	parse_mime_type (a_mime_type: STRING): HTTP_MEDIA_TYPE
+	parse_mime_type (a_mime_type: READABLE_STRING_8): HTTP_MEDIA_TYPE
 			-- Parses a mime-type into its component parts.
 			-- For example, the media range 'application/xhtml;q=0.5' would get parsed
 			-- into:
@@ -21,7 +24,7 @@ feature -- Parser
 			create Result.make_from_string (a_mime_type)
 		end
 
-	parse_media_range (a_range: STRING): HTTP_MEDIA_TYPE
+	parse_media_range (a_range: READABLE_STRING_8): HTTP_MEDIA_TYPE
 			-- Media-ranges are mime-types with wild-cards and a 'q' quality parameter.
 			-- For example, the media range 'application/*;q=0.5' would get parsed into:
 			-- ('application', '*', {'q', '0.5'})
@@ -51,7 +54,7 @@ feature -- Parser
 		end
 
 
-	fitness_and_quality_parsed (a_mime_type: STRING; parsed_ranges: LIST [HTTP_MEDIA_TYPE]): FITNESS_AND_QUALITY
+	fitness_and_quality_parsed (a_mime_type: READABLE_STRING_8; parsed_ranges: LIST [HTTP_MEDIA_TYPE]): FITNESS_AND_QUALITY
 			-- Find the best match for a given mimeType against a list of media_ranges
 			-- that have already been parsed by parse_media_range. Returns a
 			-- tuple of the fitness value and the value of the 'q' quality parameter of
@@ -148,7 +151,7 @@ feature -- Parser
 			create Result.make (best_fitness, best_fit_q)
 		end
 
-	quality_parsed (a_mime_type: STRING; parsed_ranges: LIST [HTTP_MEDIA_TYPE]): REAL_64
+	quality_parsed (a_mime_type: READABLE_STRING_8; parsed_ranges: LIST [HTTP_MEDIA_TYPE]): REAL_64
 			--	Find the best match for a given mime-type against a list of ranges that
 			--	have already been parsed by parseMediaRange(). Returns the 'q' quality
 			--	parameter of the best match, 0 if no match was found. This function
@@ -158,11 +161,11 @@ feature -- Parser
 			Result := fitness_and_quality_parsed (a_mime_type, parsed_ranges).quality
 		end
 
-	quality (a_mime_type: STRING; ranges: STRING): REAL_64
+	quality (a_mime_type: READABLE_STRING_8; ranges: READABLE_STRING_8): REAL_64
 			-- Returns the quality 'q' of a mime-type when compared against the
 			-- mediaRanges in ranges.
 		local
-			l_ranges : LIST [STRING]
+			l_ranges : LIST [READABLE_STRING_8]
 			res : ARRAYED_LIST [HTTP_MEDIA_TYPE]
 			p_res : HTTP_MEDIA_TYPE
 		do
@@ -180,15 +183,15 @@ feature -- Parser
 			Result := quality_parsed (a_mime_type, res)
 		end
 
-	best_match (supported: LIST [STRING]; header: STRING): STRING
+	best_match (supported: LIST [READABLE_STRING_8]; header: READABLE_STRING_8): READABLE_STRING_8
 			-- Choose the mime-type with the highest fitness score and quality ('q') from a list of candidates.
 		local
 			l_header_results: LIST [HTTP_MEDIA_TYPE]
 			weighted_matches: LIST [FITNESS_AND_QUALITY]
-			l_res: LIST [STRING]
+			l_res: LIST [READABLE_STRING_8]
 			p_res: HTTP_MEDIA_TYPE
 			fitness_and_quality, first_one: detachable FITNESS_AND_QUALITY
-			s: STRING
+			s: READABLE_STRING_8
 		do
 			l_res := header.split (',')
 			create {ARRAYED_LIST [HTTP_MEDIA_TYPE]} l_header_results.make (l_res.count)
@@ -285,32 +288,6 @@ feature -- Parser
 			end
 		end
 
-feature {NONE} -- Implementation
-
-	mime_type (s: STRING): STRING
-		local
-			p: INTEGER
-		do
-			p := s.index_of (';', 1)
-			if p > 0 then
-				Result := trim (s.substring (1, p - 1))
-			else
-				Result := trim (s.string)
-			end
-		end
-
-	trim (a_string: STRING): STRING
-			-- trim whitespace from the beginning and end of a string
-		require
-			valid_argument : a_string /= Void
-		do
-			a_string.left_adjust
-			a_string.right_justify
-			Result := a_string
-		ensure
-			result_same_as_argument: a_string = Result
-		end
-
 note
 	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
 	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
diff --git a/library/network/protocol/content_negotation/src/parsers/string_utils.e b/library/network/protocol/content_negotation/src/parsers/string_utils.e
new file mode 100644
index 00000000..e17ee4d3
--- /dev/null
+++ b/library/network/protocol/content_negotation/src/parsers/string_utils.e
@@ -0,0 +1,42 @@
+note
+	description: "Summary description for {STRING_UTILS}."
+	author: ""
+	date: "$Date$"
+	revision: "$Revision$"
+
+class
+	STRING_UTILS
+
+feature {NONE} -- Implementation
+
+	mime_type (s: READABLE_STRING_8): READABLE_STRING_8
+		local
+			p: INTEGER
+		do
+			p := s.index_of (';', 1)
+			if p > 0 then
+				Result := trim (s.substring (1, p - 1))
+			else
+				Result := trim (s.string)
+			end
+		end
+
+	trim (a_string: READABLE_STRING_8): READABLE_STRING_8
+			-- trim whitespace from the beginning and end of a string
+		require
+			valid_argument : a_string /= Void
+		local
+			l_result: STRING
+		do
+			l_result := a_string.as_string_8
+			l_result.left_adjust
+			l_result.right_adjust
+			Result := l_result
+		ensure
+			result_same_as_argument: Result.same_string_general (a_string)
+		end
+
+note
+	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+end
diff --git a/library/network/protocol/content_negotation/src/common_results.e b/library/network/protocol/content_negotation/src/results/common_results.e
similarity index 100%
rename from library/network/protocol/content_negotation/src/common_results.e
rename to library/network/protocol/content_negotation/src/results/common_results.e
diff --git a/library/network/protocol/content_negotation/src/language_results.e b/library/network/protocol/content_negotation/src/results/language_results.e
similarity index 100%
rename from library/network/protocol/content_negotation/src/language_results.e
rename to library/network/protocol/content_negotation/src/results/language_results.e
diff --git a/library/network/protocol/content_negotation/src/parse_results.e b/library/network/protocol/content_negotation/src/results/parse_results.e
similarity index 100%
rename from library/network/protocol/content_negotation/src/parse_results.e
rename to library/network/protocol/content_negotation/src/results/parse_results.e
diff --git a/library/network/protocol/content_negotation/src/variant_results.e b/library/network/protocol/content_negotation/src/variant_results.e
deleted file mode 100644
index e14f133a..00000000
--- a/library/network/protocol/content_negotation/src/variant_results.e
+++ /dev/null
@@ -1,55 +0,0 @@
-note
-	description: "Summary description for {VARIANT_RESULTS}."
-	author: ""
-	date: "$Date$"
-	revision: "$Revision$"
-
-class
-	VARIANT_RESULTS
-
-feature -- Mime, Language, Charset and Encoding Results
-
-	mime_result: detachable STRING
-
-	set_mime_result (a_mime: STRING)
-			-- set the mime_result with `a_mime'
-		do
-			mime_result := a_mime
-		ensure
-			set_mime_result: a_mime = mime_result
-		end
-
-	language_result: detachable STRING
-
-	set_language_result (a_language: STRING)
-			-- set the language_result with `a_language'
-		do
-			language_result := a_language
-		ensure
-			set_language: a_language = language_result
-		end
-
-	charset_result: detachable STRING
-
-	set_charset_result (a_charset: STRING)
-			-- set the charset_result with `a_charset'
-		do
-			charset_result := a_charset
-		ensure
-			set_charset: a_charset = charset_result
-		end
-
-	encoding_result: detachable STRING
-
-	set_encoding_default (an_encoding: STRING)
-		do
-			encoding_result := an_encoding
-		ensure
-			set_encoding: an_encoding = encoding_result
-		end
-
-note
-	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
-	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
-
-end
diff --git a/library/network/protocol/content_negotation/src/variants/character_encoding_variant_results.e b/library/network/protocol/content_negotation/src/variants/character_encoding_variant_results.e
new file mode 100644
index 00000000..e9ef1b71
--- /dev/null
+++ b/library/network/protocol/content_negotation/src/variants/character_encoding_variant_results.e
@@ -0,0 +1,39 @@
+note
+	description: "Summary description for {CHARACTER_ENCODING_VARIANT_RESULTS}."
+	author: ""
+	date: "$Date$"
+	revision: "$Revision$"
+
+class
+	CHARACTER_ENCODING_VARIANT_RESULTS
+
+inherit
+
+	VARIANT_RESULTS
+	
+feature -- Access
+
+	character_type: detachable READABLE_STRING_8
+
+
+feature -- Change Element
+
+	set_character_type (a_character_type: READABLE_STRING_8)
+			-- Set `character_type' with `a_character_type'
+		do
+			character_type := a_character_type
+		ensure
+			character_type_set: character_type /= Void implies a_character_type = character_type
+		end
+
+	set_variant_header
+			-- Set variant header as `Accept-Charset'
+		do
+			variant_header := "Accept-Charset"
+		end
+
+note
+	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+
+end
diff --git a/library/network/protocol/content_negotation/src/variants/compression_variant_results.e b/library/network/protocol/content_negotation/src/variants/compression_variant_results.e
new file mode 100644
index 00000000..b23e944c
--- /dev/null
+++ b/library/network/protocol/content_negotation/src/variants/compression_variant_results.e
@@ -0,0 +1,41 @@
+note
+	description: "Summary description for {COMPRESSION_VARIANT_RESULTS}."
+	author: ""
+	date: "$Date$"
+	revision: "$Revision$"
+	EIS: "name= Compression", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3", "protocol=uri"
+
+class
+	COMPRESSION_VARIANT_RESULTS
+
+inherit
+
+	VARIANT_RESULTS
+	
+feature -- Access
+
+	compression_type: detachable READABLE_STRING_8
+			-- Compression variant for the response
+
+
+feature -- Change Element
+
+	set_compression_type (a_compression_type: READABLE_STRING_8)
+			-- Set `compression_type' with `a_compression_type'
+		do
+			compression_type := a_compression_type
+		ensure
+			compression_type_set: attached compression_type as l_compression_type implies l_compression_type = a_compression_type
+		end
+
+	set_variant_header
+			-- Set variant_header as `Accept-Encoding'
+		do
+			variant_header := "Accept-Encoding"
+		end
+
+note
+	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+
+end
diff --git a/library/network/protocol/content_negotation/src/variants/language_variant_results.e b/library/network/protocol/content_negotation/src/variants/language_variant_results.e
new file mode 100644
index 00000000..237f6608
--- /dev/null
+++ b/library/network/protocol/content_negotation/src/variants/language_variant_results.e
@@ -0,0 +1,41 @@
+note
+	description: "Summary description for {LANGUAGE_VARIANT_RESULTS}."
+	author: ""
+	date: "$Date$"
+	revision: "$Revision$"
+
+class
+	LANGUAGE_VARIANT_RESULTS
+
+inherit
+
+	VARIANT_RESULTS
+
+feature -- Access
+
+	language_type: detachable READABLE_STRING_8
+			-- language variant for the response
+
+feature -- Change Element
+
+
+	set_language_type (a_language_type: READABLE_STRING_8)
+			-- Set `language_type' with `a_language_type'
+		do
+			language_type := a_language_type
+		ensure
+			language_type_set:  attached language_type as l_language_type implies l_language_type = a_language_type
+		end
+
+	set_variant_header
+			-- Set variant header as 'Accept-Language'
+		do
+			variant_header := "Accept-Language"
+		end
+
+
+note
+	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+
+end
diff --git a/library/network/protocol/content_negotation/src/variants/media_type_variant_results.e b/library/network/protocol/content_negotation/src/variants/media_type_variant_results.e
new file mode 100644
index 00000000..1be25691
--- /dev/null
+++ b/library/network/protocol/content_negotation/src/variants/media_type_variant_results.e
@@ -0,0 +1,39 @@
+note
+	description: "Summary description for {MEDIA_TYPE_VARIANT_RESULTS}."
+	author: ""
+	date: "$Date$"
+	revision: "$Revision$"
+
+class
+	MEDIA_TYPE_VARIANT_RESULTS
+
+inherit
+
+	VARIANT_RESULTS
+
+feature -- Access
+
+	media_type: detachable READABLE_STRING_8
+
+feature -- Change Element
+
+	set_media_type (a_media_type: READABLE_STRING_8)
+			-- Set `media_type' as `a_media_type'
+		do
+			media_type := a_media_type
+		ensure
+			media_type_set: attached media_type as l_media_type implies l_media_type = a_media_type
+		end
+
+	set_variant_header
+			-- Set variant header as `Accept'
+		do
+			variant_header := "Accept"
+		end
+
+
+note
+	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+
+end
diff --git a/library/network/protocol/content_negotation/src/variants/variant_results.e b/library/network/protocol/content_negotation/src/variants/variant_results.e
new file mode 100644
index 00000000..33aeef7a
--- /dev/null
+++ b/library/network/protocol/content_negotation/src/variants/variant_results.e
@@ -0,0 +1,71 @@
+note
+	description: "Summary description for {VARIANT_RESULTS}."
+	author: ""
+	date: "$Date$"
+	revision: "$Revision$"
+
+deferred class
+	VARIANT_RESULTS
+
+feature -- Access
+
+	variant_header: detachable READABLE_STRING_8
+			-- variant header for the response
+
+	supported_variants: detachable LIST [READABLE_STRING_8]
+			-- Set of supported variants for the response
+
+	is_acceptable: BOOLEAN
+			-- is the current variant accepted?
+
+	accept_headers_set: ARRAY[READABLE_STRING_8]
+			-- Set of valid accept headers headers
+		note
+			EIS:"name=Accept", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.1", "protocol=uri"
+			EIS:"name=Accept-Charset", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.2", "protocol=uri"
+			EIS:"name=Accept-Encoding", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3", "protocol=uri"
+			EIS:"name=Accept-Language", "src=http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.4", "protocol=uri"
+		once
+			Result:= <<"Accept","Accept-Language","Accept-Encoding","Accept-Charset">>
+			Result.compare_objects
+		end
+
+feature -- Status_Report
+
+	is_valid_header (a_header: READABLE_STRING_8): BOOLEAN
+			-- is `a_header' a valid accept header?
+		do
+			Result := accept_headers_set.has (a_header)
+		end
+
+feature -- Change Element
+
+	set_acceptable (acceptable: BOOLEAN)
+			-- Set `is_acceptable' with `acceptable'
+		do
+			is_acceptable := acceptable
+		ensure
+			is_acceptable_set: is_acceptable = acceptable
+		end
+
+
+	set_variant_header
+			-- Set variant header
+		deferred
+		ensure
+			is_valid_header_set : attached variant_header as l_header implies is_valid_header (l_header)
+		end
+
+	set_supported_variants (a_supported: LIST [READABLE_STRING_8])
+			-- Set `supported vairants' with `a_supported'
+		do
+			supported_variants := a_supported
+		ensure
+			set_supported_variants: attached supported_variants as l_supported_variants  implies l_supported_variants = a_supported
+		end
+
+note
+	copyright: "2011-2013, Javier Velilla, Jocelyn Fiat, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+
+end
diff --git a/library/network/protocol/content_negotation/test/conneg_server_side_test.e b/library/network/protocol/content_negotation/test/conneg_server_side_test.e
index e9d181f4..c946c00d 100644
--- a/library/network/protocol/content_negotation/test/conneg_server_side_test.e
+++ b/library/network/protocol/content_negotation/test/conneg_server_side_test.e
@@ -117,7 +117,7 @@ feature -- Test routines
 			--Scenario 3, the server select the best match, and set the vary header
 			l_compression := "gzip"
 			compression_supported := l_compression.split(',')
-			conneg.set_encoding_defautl ("gzip")
+			conneg.set_encoding_default("gzip")
 			compression_variants := conneg.encoding_preference (compression_supported, "compress,gzip;q=0.7")
 			assert ("Expected Acceptable", compression_variants.is_acceptable)
 			assert ("Variants is dettached",compression_variants.supported_variants = Void)