Header Type Of Message

Now most popular typical communication in ATM is using TCP-IP. In messages using the TCP/IP communications protocol, a header can be inserted 

at the beginning and the end of the message containing the length of the message. There are many types of header.
for example we will used command for inservice. from NDC+ for inservice we use ;

1.000.000.1

1 = Message Class terminal Command
. = Field Separtor, 1c in hexa
000 = Logical Unit Number / Luno
. = Field Separator
000 = Message Sequence number
. = Field Separator, 1c in hexa
1 = Command code , 1 for go inservice.

in Hexa format
31 1C 20 20 20 1C 20 20 20 1C 31

  

1. No Header.
  If using No Header, the message just sending in plain text. like below message.
  1.000.000.1 = asccii
  31 1C 20 20 20 1C 20 20 20 1C 31 = hexa

2 STX and ETX Header
  The header consists of an STX character followed by a two bytes binary
  message length. An ETX is ending the message. The two length bytes are not
  included in the message length 
  [STX]1.000.000.1[ETX]
  02 31 1C 20 20 20 1C 20 20 20 1C 31 03

3. ASCII Header
  The header consists of the message length expressed as four ASCII decimal
  digits. The four length bytes are not included in the message length.
  00 05 31 1C 1C 1C 31 - in hexa
  ..1...1 = in ASCII , we count The message is 5 = 1...1 (without Luno and Msg sequence number)

4 Two bytes Hexa
  The header consists of the message length expressed as a two bytes binary
  value, MSB byte first. The header length is not included in the message length
  ..1.000.000.1 = in ascii
  00 0C 31 20 1C 20 20 20 1C 20 20 20 1C 31 = in hexa , 00 0C is header