Components of the iWay Integration Solution for SWIFT

The basic header block has the following format:

{1:    F    01   BANKBEBB   2222   123456}
(a)   (b)  (c)   (d)        (e)    (f)

Note: Blank spaces have been added for readability purposes.

The basic header block has a fixed length and is continuous with no field separators:

a) Block ID - always '1:'
b) Application ID - F = FIN, A = GPA or L = GPA (logins, etc)
c) Service ID - 01 = FIN/GPA, 21 = ACK/NAK
d) LT address - 12 Characters, must not have 'X' in position 9
e) Session number - added by the CBT (Computer Based Terminal), padded with zeroes
f) Sequence number - added by the CBT (Computer Based Terminal), padded with zeroes

The application header block has a different format depending on whether it is being sent to or from SWIFT.

The input structure (to SWIFT) is:

{2:    I     100    BANKDEFFXXXX    U       3       003}
(a)    (b)   (c)    (d)             (e)     (f)     (g)

Note: Blank spaces have been added for readability purposes.

This structure has a fixed length and is continuous with no field separators from user to SWIFT.

a) Block ID - always '2:'
b) I = Input
c) Message Type
d) Receivers address with X in position 9 and padded with X's if no branch
e) Message Priority - S = System, N = Normal, U = Urgent
f) Delivery Monitoring - 1 = Non Delivery Warning (MT010)
                         2 = Delivery Notification (MT011)
                         3 = Both Valid = U1 or U3, N2 or just N
g) Obsolescence Period - when a non delivery notification is generated
   Valid for U = 003 (15 minutes)
   Valid for N = 020 (100 minutes)

The output structure (from SWIFT) is:

{2:   O      100   1200   970103BANKBEBBAXXX2222123456   970103  1201   N}
(a)  (b)     (c)   (d)    (e)                            (f)     (g)   (h)

This structure has a fixed length and is continuous with no field separators from user to SWIFT.

a) Block ID - always '2:'
b) O = Output
c) Message Type
d) Input time with respect to the Sender
e) MIR with Senders address
f) Output date with respect to Receiver
g) Message priority

The user header block has the following structure:

{3:  {113:xxxx}  {108:abcdefgh12345678}     }
(a)  (b)         ( c)

Note: Blank spaces have been added for readability purposes.

This is an optional block and is similar in structure to system messages.

a) Block ID - always '3:'
b) Optional banking priority code
c) Message User Reference MUR used by applications for reconciliation with ACK

Other tags exist such as 119 which can contain the code ISITC on an MT521 or 523 providing the sender and receiver are registered to do so with SWIFT. This forces additional code word and formatting rules validation of the body of the message as laid down by ISITC (Industry Standardization for Institutional Trade Communication).

113. 4 characters (SWIFT x Character Type) Banking Priority: (HYnn) H- Highly Urgent, U- Urgent, N- Normal, Y- Request Receiving, N- Do Not Request Receiving, nn- May or may not be used.

108. 16 characters (SWIFT x Character Type) MUR (Message User Reference). 1234459898ABC used to reconcile with ACKs.

119. 8 uppercase characters or numbers. Bank User Defined.

This block is where the actual MTnnn message is specified and is what most users will see. Generally the other blocks are stripped off before presentation. The format is as follows:

{4:
:20:123456
:25:123-456789
:28C:102
:60F:C020527EUR3723495,
:61:020528D1,2FBNK494935/DEV//67914
:61:020528D30,2NCHK78911//123464
:61:020528D250,NCHK67822//123460
:61:020528D450,S103494933/DEV//P064118
FAVOUR K. DESMID
:61:020528D500,NCH45633//123456
:61:020528D1058,47S103494931//3841188
FAVOUR H. F. JASSEN
:61:020528D2500,NCHK56728//123457
:61:020528D3840,S103494935//3841189
FAVOUR H. F. JANSSEN
:61:020528D5000,S20023/200516//47829
ORDER ROTTERDAM
:62F:C020528EUR3709865,13
-}

The example above is an MT950, Statement Of Cash. Fields specified are in accordance to the appropriate volume of the user handbook, there is one or more for each message category.

The format of field tags is:

:nna:
nn - numbers
a - optional letter which may be present on selected tags
eg - :20:  Transaction Reference Number
     :25: Account Identification
The length of a field is designated thus:
nn      -   maximum length
nn!     -   fixed length
nn-nn   -   minimum and maximum length
nn * nn -   max number of lines times max 
            line length

The format of the data is designated thus:

n      -   Digits
 d      -   Digits with decimal comma
 h      -   Uppercase hexadecimal
 a      -   Uppercase letters
 c      -   Uppercase alphanumeric
 e      -   Space
 x      -   S.W.I.F.T. character set
 y      -   Upper case level A ISO 9735 characters
 z      -   S.W.I.F.T. extended character set

Some fields are defined as optional and if not required they must not be present as no blank fields must be present in the message.

/,word  -   Characters as-is
 […]        -   optional element

For example:

4!c[/30x]   -   fixed 4 uppercase alphanumeric, optionally followed by a slash
                and up to 30 S.W.I.F.T. characters
ISIN1!e12!c -   code word followed by a space and fixed 12 uppercase alphanumerics

In some message types certain fields will be defined as conditional, for example, if a certain field is present then another field may change from optional to mandatory or forbidden.

Certain fields have different formats dependant on the option which is chosen, which is designated by a letter after the tag number, for example:

:32A:000718GBP1000000,00    Value Date, ISO Currency and Amount
:32B:GBP1000000,00          ISO Currency and Amount

It is important to note that the S.W.I.F.T. standards for Amount formats are, no thousand separators and a comma for a decimal separator.

:58A:NWBKGB2L               Beneficiary S.W.I.F.T. address
:58D:NatWest Bank           Beneficiary full name and address
Head Office
London

115--> 32 characters (SWIFT x Character Type)SWIFT x Character Types= 0-9,a-z, A-Z, /-?:().,'+

A message always ends in a trailer with the following format:

{5: {MAC:12345678}{CHK:123456789ABC}

It contains a number of fields that are denoted by keywords such as:

• MAC: Message Authentication Code calculated based on the entire contents of the message using a key that has been exchanged with the destination and a secret algorithm. Found on message categories 1,2,4,5,7,8, Most 6's and the 304.
• CHK: Checksum calculated for all message types.
• PDE: Possible Duplicate Emission added if user thinks that they may have sent the message previously.
• PDM: Possible Duplicate Message added by S.W.I.F.T. if they think that a message may have been transmitted previously.
• DLM: Added by S.W.I.F.T. if an Urgent message has not been delivered within 15 minutes or a Normal message within 100 minutes.