Update Network layer protection guidance in CAEP Interoperability Pro…

…file (#213)

* Update Network layer protection guidance in CAEP Interoperability Profile

Fixes #212

* Use TLS version independent guidance for SSF transmitter

---------

Co-authored-by: Thomas Darimont <thomas.darimont@oidf.org>

openid-caep-interoperability-profile-1_0.md

@@ -74,7 +74,7 @@ normative:
         ins: A. Tulshibagwale
         name: Atul Tulshibagwale
         org: SGNL
-  RFC7525: # Recommendations for Secure Use of Transport Layer Security
+  RFC9325: # Recommendations for Secure Use of Transport Layer Security (TLS) and Datagram Transport Layer Security (DTLS)
   RFC6125: # Representation and Verification of Domain-Based Application Service Identity within Internet Public Key 
            # Infrastructure Using X.509 (PKIX) Certificates in the Context of Transport Layer Security (TLS)
   RFC6750: # The OAuth 2.0 Authorization Framework: Bearer Token Usage
@@ -125,7 +125,7 @@ The following requirements are common across all use-cases defined in this docum
 
 ## Network layer protection
 * The SSF transmitter MUST offer TLS protected endpoints and MUST establish connections to other servers using TLS. TLS connections MUST be set up to use TLS version 1.2 or later.
-* When using TLS 1.2, follow the recommendations for Secure Use of Transport Layer Security in [RFC7525]{{RFC7525}}.
+* The SSF transmitter MUST follow the recommendations for Secure Use of Transport Layer Security in [RFC9325]{{RFC9325}}.
 * The SSF receiver MUST perform a TLS server certificate signature checks, chain of trust validations, expiry and revocation status checks before calling the SSF transmitter APIs, as per [RFC6125]{{RFC6125}}.
 
 ## CAEP specification version