diff --git a/lib/qasim/map.rb b/lib/qasim/map.rb
index c91f00a..b99e08a 100644
--- a/lib/qasim/map.rb
+++ b/lib/qasim/map.rb
@@ -9,4 +9,91 @@ module Qasim ; module Map
 	class ParseError < RuntimeError ; end
 	class ConnectError < RuntimeError ;	end
 
+  module_function :from_file
+
+  def from_file
+
+  end
+
+  def to_file
+  end
+
+
+  #
+  # replace magic values withing map lines
+  #
+  # Allowed values :
+  #
+  # $(var) => variable value from environment
+  # ${var} => variable value from environment
+  # 
+  def env_substitute str, lineno
+		local_env = ENV.clone
+		while str =~ /\$(\w+)/ do
+			case str
+			when /\$\{(.+)\}/ then
+				pattern = $1
+				str.gsub!(/\$\{#{pattern}\}/,local_env[pattern])
+			when /\$(\w+)/ then
+				pattern = $1
+				str.gsub!(/\$#{pattern}/,local_env[pattern])
+			else 
+				puts "w: unknown pattern: %s at str %d"  % [str, lineno]
+			end
+		end
+    str
+  end
+
+	#
+	# Load map description from file
+	#
+	def from_file filename
+		f = File.open filename
+		linect = 0
+		f.each do |line|
+			line = line.strip
+			linect += 1
+
+      line = env_substitute(line, linect)
+
+			case line
+			when /^\s*REMOTE_USER\s*=\s*(.*)\s*$/ then
+				@user = $1
+				#rdebug "d: remote_user => #{$1}"
+			when /^\s*REMOTE_PORT\s*=\s*(.*)\s*$/ then
+				@port = $1.to_i
+				#rdebug "d: remote_port => #{$1}"
+			when /^\s*REMOTE_HOST\s*=\s*(.*)\s*$/ then
+				@host = $1
+				#rdebug "d: remote_host => #{$1}"
+			when /^\s*REMOTE_CYPHER\s*=\s*(.*)\s*$/ then
+				if CYPHERS.map{|x| x.to_s}.include? $1 then
+					@host = $1.to_sym
+				end
+			when /^\s*MAP\s*=\s*(.*)\s+(.*)\s*$/ then
+				@links[$1] = $2
+				#rdebug "d: link #{$1} => #{$2}"
+			when /^\s*$/,/^\s*#/ then
+				#rdebug "d: dropping empty line"
+			else
+				raise MapParseError, "parse error at #{@filename}:#{linect}"
+			end
+		end
+		f.close
+	end
+
+
+	#
+	# Write map description to file
+	#
+	def write path=nil
+		@path=path unless path.nil?
+
+		File.open(@path, "w") do |f|
+			f.puts "REMOTE_USER=%s" % @user
+			f.puts "REMOTE_PORT=%s" % @port
+			f.puts "REMOTE_HOST=%s" % @host
+			f.puts "REMOTE_CYPHER=%s" % @cypher
+		end
+	end
 end ; end
diff --git a/lib/qasim/map/generic.rb b/lib/qasim/map/generic.rb
new file mode 100644
index 0000000..1a3c915
--- /dev/null
+++ b/lib/qasim/map/generic.rb
@@ -0,0 +1,5 @@
+require 'fileutils'
+require 'qasim/map'
+
+class Qasim::Map::Generic
+end
diff --git a/lib/qasim/map/ssh.rb b/lib/qasim/map/ssh.rb
index 32a3747..f257084 100644
--- a/lib/qasim/map/ssh.rb
+++ b/lib/qasim/map/ssh.rb
@@ -1,217 +1,148 @@
 
 require 'fileutils'
 require 'qasim/map'
+require 'qasim/map/generic'
 
-module Qasim::Map
-	class Ssh
-		attr_reader :path,
-		   	:host, 
-			:port, 
-			:enable, 
-			:user, 
-			:map,
-			:name
+class Qasim::Map::Ssh < Qasim::Map::Generic
+	attr_reader :path,
+		:host, 
+		:port, 
+		:enable, 
+		:user, 
+		:map,
+		:name
 
-		CYPHER_ARCFOUR = :arcfour
-		CYPHER_AES256CBC = "aes-256-cbc".to_sym
-		CYPHERS = [ CYPHER_ARCFOUR, CYPHER_AES256CBC ]
+	CYPHER_ARCFOUR = :arcfour
+	CYPHER_AES256CBC = "aes-256-cbc".to_sym
+	CYPHERS = [ CYPHER_ARCFOUR, CYPHER_AES256CBC ]
 
 
-		#
-		# Set defaults properties for maps
-		#
-		def initialize config, map_path
-			@config = config
-			@path = map_path
-			@host = nil
-			@port = 22
-			@enable = false
-			@user = nil
-			@cypher = :arcfour
-			@links = {}
-			@debug = false
-			@name = (File.basename map_path).gsub(/\.map$/,'')
+	#
+	# Set defaults properties for maps
+	#
+	def initialize config, map_path
+		@config = config
+		@path = map_path
+		@host = nil
+		@port = 22
+		@enable = false
+		@user = nil
+		@cypher = :arcfour
+		@links = {}
+		@debug = false
+		@name = (File.basename map_path).gsub(/\.map$/,'')
 
-			self.load @path
+		self.load @path
+	end
+
+
+
+
+	#
+	# Test map liveness (how ?)
+	# FIXME: not implemented
+	#
+	def online?
+		#rdebug  "testing online? %s " % self.inspect
+		#FIXME: test liveness
+	end
+
+
+	#
+	# Test if map is connected / mounted
+	#
+	def connected? 
+		f = File.open("/proc/mounts")
+		sshfs_mounted = (f.readlines.select do |line|
+			line =~ /\s+fuse.sshfs\s+/
+		end).map do |line| 
+			line.split(/\s+/)[1]
 		end
+		f.close
 
+		score = 0
+		@links.each do |name, remotepath|
+			score += 1
+			local_path = File.join @config.mnt_dir, name
 
-		#
-		# Load map description from file
-		#
-		def load path=nil
-			@path=path unless path.nil?
-			#rdebug "Parsing map #{@path}"
-			f = File.open @path
-			linect = 0
-			local_env = ENV.clone
-			f.each do |line|
-				line = line.strip
-				linect += 1
-
-				while line =~ /\$(\w+)/ do
-					#puts "FOUND PATTERN %s => %s" % [$1, local_env[$1]]
-					case line
-					when /\$\{(.+)\}/ then
-						pattern = $1
-						puts pattern
-						line.gsub!(/\$\{#{pattern}\}/,local_env[pattern])
-					when /\$(\w+)/ then
-						pattern = $1
-						line.gsub!(/\$#{pattern}/,local_env[pattern])
-					else 
-						puts "w: unknown pattern: %s"  % line
-					end
-				end
-
-				case line
-				when /^\s*REMOTE_USER\s*=\s*(.*)\s*$/ then
-					@user = $1
-					#rdebug "d: remote_user => #{$1}"
-				when /^\s*REMOTE_PORT\s*=\s*(.*)\s*$/ then
-					@port = $1.to_i
-					#rdebug "d: remote_port => #{$1}"
-				when /^\s*REMOTE_HOST\s*=\s*(.*)\s*$/ then
-					@host = $1
-					#rdebug "d: remote_host => #{$1}"
-				when /^\s*REMOTE_CYPHER\s*=\s*(.*)\s*$/ then
-					if CYPHERS.map{|x| x.to_s}.include? $1 then
-						@host = $1.to_sym
-					end
-				when /^\s*MAP\s*=\s*(.*)\s+(.*)\s*$/ then
-					@links[$1] = $2
-					#rdebug "d: link #{$1} => #{$2}"
-				when /^\s*$/,/^\s*#/ then
-					#rdebug "d: dropping empty line"
-				else
-					raise MapParseError, "parse error at #{@path}:#{linect}"
-				end
-			end
-			f.close
-		end
-
-
-		#
-		# Write map description to file
-		#
-		def write path=nil
-			@path=path unless path.nil?
-
-			File.open(@path, "w") do |f|
-				f.puts "REMOTE_USER=%s" % @user
-				f.puts "REMOTE_PORT=%s" % @port
-				f.puts "REMOTE_HOST=%s" % @host
-				f.puts "REMOTE_CYPHER=%s" % @cypher
+			if sshfs_mounted.include? local_path then
+				score -= 1
 			end
 		end
-
-
-		#
-		# Test map liveness (how ?)
-		# FIXME: not implemented
-		#
-		def online?
-			#rdebug  "testing online? %s " % self.inspect
-			#FIXME: test liveness
+		if score == 0 then return true
+		else return false
+			# FIXME: explain why ?
 		end
+	end
 
 
+	#
+	# Connect map
+	#
+	def connect &block
+		puts "[#{File.basename @path}] Connecting..."
+		puts "  #{@user}@#{@host}:#{@port}"
+		#puts "  links = %s" % @links.map{ |k,v| "%s => %s" % [ k, v ] }.join(', ')
+		# do something
+		# test server connection
+		# mount
 		#
-		# Test if map is connected / mounted
-		#
-		def connected? 
-			f = File.open("/proc/mounts")
-			sshfs_mounted = (f.readlines.select do |line|
-				line =~ /\s+fuse.sshfs\s+/
-			end).map do |line| 
-					line.split(/\s+/)[1]
-			end
-			f.close
-
-			score = 0
-			@links.each do |name, remotepath|
-				score += 1
-				local_path = File.join @config.mnt_dir, name
-
-				if sshfs_mounted.include? local_path then
-					score -= 1
-				end
-			end
-			if score == 0 then return true
-			else return false
-				# FIXME: explain why ?
-			end
-		end
-
-
-		#
-		# Connect map
-		#
-		def connect &block
-			puts "[#{File.basename @path}] Connecting..."
-			puts "  #{@user}@#{@host}:#{@port}"
-			#puts "  links = %s" % @links.map{ |k,v| "%s => %s" % [ k, v ] }.join(', ')
-			# do something
-			# test server connection
-			# mount
-			#
-			# FIXME: test connexion with Net::SSH + timeout or ask password
-			@links.each do |name, remotepath|
-				localpath = File.join ENV['HOME'], "mnt", name
-				FileUtils.mkdir_p localpath
-				cmd = "sshfs"
-				cmd_args = [
-					"-o","allow_root" ,
-					"-o","idmap=user" ,
-					"-o","uid=%s" % Process.uid,
-					"-o","gid=%s" % Process.gid,
-					"-o","reconnect", # auto-reconnection
-					"-o","workaround=all",
-					"-o","cache_timeout=900", # 15 min cache for files
-					"-o","cache_stat_timeout=1800", # 30 min cache for directories
-					"-o","cache_link_timout=1800", # 30 min cache for links
-					"-o","attr_timeout=1800", # 30 min attr cache
-					"-o","entry_timeout=1800", # 30 min entry cache
-					"-o","ServerAliveInterval=15", # prevent I/O hang
-					"-o","ServerAliveCountMax=3", # prevent I/O hang
-					"-o","no_readahead",
-					#"-o","Ciphers=arcfour", # force cypher
-					"-o","Port=%s" % @port,
-					"%s@%s:%s" % [@user,@host,remotepath],
-					localpath ]
-				#rdebug "command: %s" % [ cmd, cmd_args ].flatten.join(' ')
-				if block_given? then
-					yield name, cmd, cmd_args
-				else
-					system cmd, cmd_args
-					if $?.exitstatus != 0 then
-						raise ConnectError, self
-					end
+		# FIXME: test connexion with Net::SSH + timeout or ask password
+		@links.each do |name, remotepath|
+			localpath = File.join ENV['HOME'], "mnt", name
+			FileUtils.mkdir_p localpath
+			cmd = "sshfs"
+			cmd_args = [
+				"-o","allow_root" ,
+				"-o","idmap=user" ,
+				"-o","uid=%s" % Process.uid,
+				"-o","gid=%s" % Process.gid,
+				"-o","reconnect", # auto-reconnection
+				"-o","workaround=all",
+				"-o","cache_timeout=900", # 15 min cache for files
+				"-o","cache_stat_timeout=1800", # 30 min cache for directories
+				"-o","cache_link_timout=1800", # 30 min cache for links
+				"-o","attr_timeout=1800", # 30 min attr cache
+				"-o","entry_timeout=1800", # 30 min entry cache
+				"-o","ServerAliveInterval=15", # prevent I/O hang
+				"-o","ServerAliveCountMax=3", # prevent I/O hang
+				"-o","no_readahead",
+				#"-o","Ciphers=arcfour", # force cypher
+				"-o","Port=%s" % @port,
+				"%s@%s:%s" % [@user,@host,remotepath],
+				localpath ]
+			#rdebug "command: %s" % [ cmd, cmd_args ].flatten.join(' ')
+			if block_given? then
+				yield name, cmd, cmd_args
+			else
+				system cmd, cmd_args
+				if $?.exitstatus != 0 then
+					raise ConnectError, self
 				end
 			end
 		end
+	end
 
 
-		#
-		# Disconnect map
-		#
-		def disconnect &block
-			puts "Disconnecting map #{@path}"
-			@links.each do |name, remotepath|
-				localpath = File.join ENV['HOME'], "mnt", name
-				cmd = "fusermount"
-				cmd_args = [
-					"-u", #umount
-					"-z" ,#lazy
-					localpath ]
-				#rdebug "command: %s" % [ cmd, cmd_args ].flatten.join(' ')
-				if block_given? then
-					yield name, cmd, cmd_args
-				else
-					system cmd, cmd_args
-					if $?.exitstatus != 0 then
-						raise ConnectError, self
-					end
+	#
+	# Disconnect map
+	#
+	def disconnect &block
+		puts "Disconnecting map #{@path}"
+		@links.each do |name, remotepath|
+			localpath = File.join ENV['HOME'], "mnt", name
+			cmd = "fusermount"
+			cmd_args = [
+				"-u", #umount
+				"-z" ,#lazy
+				localpath ]
+			#rdebug "command: %s" % [ cmd, cmd_args ].flatten.join(' ')
+			if block_given? then
+				yield name, cmd, cmd_args
+			else
+				system cmd, cmd_args
+				if $?.exitstatus != 0 then
+					raise ConnectError, self
 				end
 			end
 		end
diff --git a/lib/qasim/map/webdav.rb b/lib/qasim/map/webdav.rb
new file mode 100644
index 0000000..4da6c6f
--- /dev/null
+++ b/lib/qasim/map/webdav.rb
@@ -0,0 +1,11 @@
+
+require 'fileutils'
+require 'qasim/map'
+require 'qasim/map/generic'
+
+class Qasim::Map::Webdav
+    # nothing
+    def initialize
+    end
+end
+
diff --git a/spec/map_ssh_spec.rb b/spec/map_ssh_spec.rb
index d8e1481..c56fc62 100644
--- a/spec/map_ssh_spec.rb
+++ b/spec/map_ssh_spec.rb
@@ -1,7 +1,7 @@
 
 require_relative 'spec_helper'
-require 'qasim/map_ssh'
+require 'qasim/map/ssh'
 
-describe Qasim::Config do
+describe Qasim::Map::Ssh do
   # something
 end
diff --git a/spec/map_webdav_spec.rb b/spec/map_webdav_spec.rb
new file mode 100644
index 0000000..8bf0821
--- /dev/null
+++ b/spec/map_webdav_spec.rb
@@ -0,0 +1,8 @@
+
+require_relative 'spec_helper'
+require 'qasim/map/webdav'
+
+describe Qasim::Map::Webdav do
+  # something
+end
+