diff --git a/pom.xml b/pom.xml
index edbf89e..a2107ad 100644
--- a/pom.xml
+++ b/pom.xml
@@ -23,6 +23,11 @@
 			<artifactId>junit-jupiter</artifactId>
 			<version>5.9.1</version>
 		</dependency>
+		<dependency>
+			<groupId>com.opencsv</groupId>
+			<artifactId>opencsv</artifactId>
+			<version>5.4</version>
+		</dependency>
 	</dependencies>
 
 	<build>
diff --git a/src/main/java/fr/u_paris/gla/project/io/NetworkFormat.java b/src/main/java/fr/u_paris/gla/project/io/NetworkFormat.java
new file mode 100644
index 0000000..ff95c99
--- /dev/null
+++ b/src/main/java/fr/u_paris/gla/project/io/NetworkFormat.java
@@ -0,0 +1,66 @@
+/**
+ * 
+ */
+package fr.u_paris.gla.project.io;
+
+import java.text.NumberFormat;
+import java.time.Duration;
+import java.time.LocalTime;
+import java.time.format.DateTimeFormatter;
+import java.time.temporal.Temporal;
+import java.util.Locale;
+
+/** Definition of the formats of files for this project.
+ * 
+ * @author Emmanuel Bigeon */
+public final class NetworkFormat {
+
+    public static final int NUMBER_COLUMNS = 8;
+    public static final int GPS_PRECISION  = 18;
+
+    /** The index of the line name in the network format */
+    public static final int LINE_INDEX     = 0;
+    /** The index of the variant number of the segment in the network format */
+    public static final int VARIANT_INDEX  = 1;
+    /** The index of the segment trip duration in the network format */
+    public static final int DURATION_INDEX = 6;
+    /** The index of the segment distance in the network format */
+    public static final int DISTANCE_INDEX = 7;
+    /** The index of the segment end stop name in the network format */
+    public static final int STOP_INDEX     = 4;
+    /** The index of the segment starting stop name in the network format */
+    public static final int START_INDEX    = 2;
+
+    private static final DateTimeFormatter DURATION_FORMATTER         = DateTimeFormatter
+            .ofPattern("HH:mm:ss");
+    private static final NumberFormat      DURATION_SECONDS_FORMATTER = NumberFormat
+            .getIntegerInstance(Locale.ENGLISH);
+    static {
+        DURATION_SECONDS_FORMATTER.setMinimumIntegerDigits(2);
+    }
+    private static final Temporal ZERO = LocalTime.parse("00:00:00");
+
+    /** Hidden constructor for utility class */
+    private NetworkFormat() {
+        // Tool class
+    }
+
+    public static Duration parseDuration(String duration) {
+        LocalTime time = LocalTime.parse("00:" + duration, DURATION_FORMATTER);
+        return Duration.between(time, ZERO);
+    }
+
+    public static String formatDuration(Duration duration) {
+        return Long.toString(duration.toMinutes()) + ":"
+                + DURATION_SECONDS_FORMATTER.format(duration.toSecondsPart());
+    }
+
+    /** Get a formatter for the numbers in a GPS coordinate pair
+     * 
+     * @return the formatter for numbers in a GPS coordinate pair */
+    public static NumberFormat getGPSFormatter() {
+        NumberFormat instance = NumberFormat.getNumberInstance(Locale.ENGLISH);
+        instance.setMaximumFractionDigits(GPS_PRECISION);
+        return instance;
+    }
+}
diff --git a/src/main/java/fr/u_paris/gla/project/io/ScheduleFormat.java b/src/main/java/fr/u_paris/gla/project/io/ScheduleFormat.java
new file mode 100644
index 0000000..ba4a645
--- /dev/null
+++ b/src/main/java/fr/u_paris/gla/project/io/ScheduleFormat.java
@@ -0,0 +1,37 @@
+/**
+ * 
+ */
+package fr.u_paris.gla.project.io;
+
+import java.time.format.DateTimeFormatter;
+import java.time.format.ResolverStyle;
+import java.util.List;
+
+/** A tool class for the schedule format.
+ * 
+ * @author Emmanuel Bigeon */
+public final class ScheduleFormat {
+    public static final int LINE_INDEX          = 0;
+    public static final int TRIP_SEQUENCE_INDEX = 1;
+    public static final int TERMINUS_INDEX      = 2;
+    public static final int TIME_INDEX          = 3;
+
+    /** Hidden constructor for tool class */
+    private ScheduleFormat() {
+        // Tool class
+    }
+
+    /** Read a trip sequence from its string representation
+     * 
+     * @param representation the representation
+     * @return the sequence of branching */
+    public static List<Integer> getTripSequence(String representation) {
+        // TODO Read a trip sequence from a string
+
+        throw new RuntimeException("Not implemented yet");
+    }
+    
+    public static DateTimeFormatter getTimeFormatter() {
+        return DateTimeFormatter.ofPattern("HH:mm").withResolverStyle(ResolverStyle.LENIENT);
+    }
+}