diff --git a/lib/src/common/s1ap_pcap.cc b/lib/src/common/s1ap_pcap.cc
new file mode 100644
index 000000000..94e2cd9b0
--- /dev/null
+++ b/lib/src/common/s1ap_pcap.cc
@@ -0,0 +1,35 @@
+#include <stdint.h>
+#include "srslte/srslte.h"
+#include "srslte/common/pcap.h"
+#include "srslte/common/nas_pcap.h"
+
+
+namespace srslte {
+
+void nas_pcap::enable()
+{
+  enable_write = true;
+}
+void nas_pcap::open(const char* filename, uint32_t ue_id)
+{
+  pcap_file = LTE_PCAP_Open(NAS_LTE_DLT, filename);
+  ue_id = ue_id;
+  enable_write = true;
+}
+void nas_pcap::close()
+{
+  fprintf(stdout, "Saving NAS PCAP file\n");
+  LTE_PCAP_Close(pcap_file);
+}
+
+void nas_pcap::write_nas(uint8_t *pdu, uint32_t pdu_len_bytes)
+{
+    if (enable_write) {
+      NAS_Context_Info_t  context;
+      if (pdu) {
+        LTE_PCAP_NAS_WritePDU(pcap_file, &context, pdu, pdu_len_bytes);
+      }
+    }
+}
+
+}