diff --git a/session.cpp b/session.cpp
new file mode 100644
index 0000000..b80f51a
--- /dev/null
+++ b/session.cpp
@@ -0,0 +1,33 @@
+#include "session.hpp"
+
+#include <ctime>
+
+#include "endian.hpp"
+
+namespace session
+{
+
+bool Session::isSessionActive()
+{
+    auto currentTime = std::chrono::steady_clock::now();
+    auto elapsedSeconds = std::chrono::duration_cast<std::chrono::seconds>
+                          (currentTime - lastTime);
+
+    switch (state)
+    {
+        case State::SETUP_IN_PROGRESS:
+            if (elapsedSeconds < SESSION_SETUP_TIMEOUT)
+            {
+                return true;
+            }
+        case State::ACTIVE:
+            if (elapsedSeconds < SESSION_INACTIVITY_TIMEOUT)
+            {
+                return true;
+            }
+        default:
+            return false;
+    }
+}
+
+} // namespace session