1 | initial version |
If you follow the RFC chain, it seems the DUA data is scrambled.
It seems to be the correct length (56 = 0x38) but the fields, starting with version, don't make sense.
The RFC says only version 1 is supported and the screen shot shows - Version: Unknown (0)
As @anders asked above, is it possible that this is a different message type using the DUA
PPID
of 10
?
SCTP Payload Protocol Identifiers = 10 (DUA) RFC4129
RFC4129 - Digital Private Network Signaling System (DPNSS)/Digital Access Signaling System 2 (DASS 2) Extensions to the IUA Protocol
This document defines a mechanism for backhauling Digital Private Network Signaling System 1 (DPNSS 1) and Digital Access Signaling System 2 (DASS 2) messages over IP by extending the ISDN User Adaptation (IUA) Layer Protocol defined in RFC 3057.
RFC4233 (obsoletes RFC3057) - Integrated Services Digital Network (ISDN) Q.921-User Adaptation Layer
3.1. Common Message Header The protocol messages for Q.921-User Adaptation require a message header that contains the adaptation layer version, the message type, and message length. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Version | Reserved | Message Class | Message Type | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Message Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2. Common Header Format All fields in an IUA message MUST be transmitted in the network byte order, unless otherwise stated. 3.1.1. Version The version field contains the version of the IUA adaptation layer. The supported versions are the following: Value Version ----- ------- 1 Release 1.0