diff --git a/specs/iuh-notes.txt b/specs/iuh-notes.txt
new file mode 100644
index 0000000..412fe95
--- /dev/null
+++ b/specs/iuh-notes.txt
@@ -0,0 +1,47 @@
+= Specs =
+
+* TS 25.467: Home Node B Stage 2 (high level overview)
+** Figure 7.2.1 shows the protocol stack
+* TS 25.468: RUA (RANAP User Adaption), ASN.1 "SCCP Like" layer
+* TS 25.469: HNBAP signalling
+* TS 25.444: Iuh data transport (UDP/RTP/GTP use)
+* TS 25.413: RANAP
+
+
+= Protocols =
+
+== RANAP ==
+
+ASN1, BASIC-PER aligned
+
+== HNBAP ==
+
+ASN1, BASIC-PER aligned
+
+* HNB registration
+** HNB REGISTER REQ/ACC/REK
+** HNB DE-REGISTER
+* UE registration
+** UE REG/ACC/REJ
+** UE DE-REGISTER
+* RNSAP relocation
+** TNL UPD REQ/RESP/REJ
+** HNB CFG XFER REQ/RESP
+* error handling
+** ERROR IND
+
+
+
+* SABP
+* PCAP
+
+= SCTP adaption layers
+
+== RUA ==
+
+ASN1, BASIC-PER aligned
+
+* one association for each UE
+* CONNECT / TRANSFER / DISCONNECT / CONNECTIONLESS TRANSFER / ERROR
+
+== PUA ==
diff --git a/specs/ts_125413v120400p.pdf b/specs/ts_125413v120400p.pdf
new file mode 100644
index 0000000..8b68bb9
--- /dev/null
+++ b/specs/ts_125413v120400p.pdf
Binary files differ
diff --git a/specs/ts_125444v120000p.pdf b/specs/ts_125444v120000p.pdf
new file mode 100644
index 0000000..e73ed9b
--- /dev/null
+++ b/specs/ts_125444v120000p.pdf
Binary files differ
diff --git a/specs/ts_125467v120300p.pdf b/specs/ts_125467v120300p.pdf
new file mode 100644
index 0000000..a0e0b96
--- /dev/null
+++ b/specs/ts_125467v120300p.pdf
Binary files differ
diff --git a/specs/ts_125468v120100p.pdf b/specs/ts_125468v120100p.pdf
new file mode 100644
index 0000000..df4ef14
--- /dev/null
+++ b/specs/ts_125468v120100p.pdf
Binary files differ
diff --git a/specs/ts_125469v120400p.pdf b/specs/ts_125469v120400p.pdf
new file mode 100644
index 0000000..4ccde4b
--- /dev/null
+++ b/specs/ts_125469v120400p.pdf
Binary files differ