ITU-T Recommendations

Recommendation ITU-T T.38 defines the procedures to be applied to allow Group 3 facsimile transmission between terminals where, in addition to the public switched telephone network (PSTN) or integrated services digital network (ISDN), a portion of the transmission path used between terminals includes an IP network, e.g., the Internet.
This revision of this Recommendation clarifies Recommendation ITU-T H.323, Recommendation ITU-T H.248.1, session initiation protocol (SIP) and session description protocol (SDP) call establishment and improves the compatibility between ITU-T T.38 gateways and Group 3 facsimile.
Amendment 1 to Recommendation ITU-T T.38 (2010/09) introduces additions and corrections to the Recommendation and adds clause 11, "Security considerations" and Appendix VI, "Security considerations from a historical perspective". Furthermore, Amendment 1 captures items from the 'Implementers Guide' (05/2012) and from Erratum 1 (04/2013) to Recommendation ITU-T T.38 (09/2010).