Title: ATSMHS / prohibited character check in converted AMHS messages

PDR Reference: 97060017

Originator Reference: 

SARPs Document Reference: ATSMHS Section 3.1.2.3.5.2.2.9

Status: 	SUBMITTED ->	FORWARDED	17/10/97

PDR Revision Date: 17/10/97

PDR Submission Date: 27/06/97

Submitting State/Organization: Aena, Spain

Submitting Author Name: Cid J.

Submitting Author E-mail Address: jcid@ugdna.aena.es

Submitting Author Supplemental Contact Information: 
Jesus CID
AENA
Juan Ignacio de Tena, 14
28027 Madrid  SPAIN

SARPs Date: ICAO version 1.1 (Phuket output)

SARPs Language: english

Summary of Defect:

Related to the conversion of each character which is not in the IA5IRV 
character repertoire into an IA5IRV character according to the locally 
defined conversion rules that is automatically performed by the 
commercial APIs, it would be taken into consideration:

- The possibility of receiving within the text of IPM message 
characters or character sequences not authorized in Annex 10, Volume 
II, 4.1.2 (i.e., 'ZCZC' sequence...) is very low.

- Besides, this activity would dramatically decrease the general 
system performance due to an exhaustived checking of the text of the 
converted AFTN message, character by character, would have to be 
implemented.

Would this decrease of the system performance compensate the remote 
posibility of occuring those forbiden characters or character 
sequences in the text ?.

Assigned SME: Sub-Volume 3 SME

Proposed SARPs amendment:
Delete the c) item of this paragraph (3.1.2.3.5.2.2.9) in the SARP. 
This clause could be maintained as a recomendation in the Guidance 
Material.

SME Recommendation to CCB: <resolve, reject, forward>

CCB Decision:		FORWARDED