Byte

Description

0, 1

Tag 0x274F

2, 3

Length Variable

4

Value[0] Coding Standard

0x00 CCITT Standardized Coding

0x01 ISO/IEC Standard

0x02 National Standard

0x03 Standard specific to identified location

5

Value[1] Location

0x00 User

0x01 Private network serving the local user

0x02 Public network serving the local user

0x04 Public network serving the remote user

0x05 Private network serving the remote user

0x06 Network beyond the Interworking point

6

Value[2] Progress Descriptor

0x00 (or 0x80*) Call is not end to end of same protocol

0x02 (or 0x82*) Destination address is non-ISDN

0x03 (or 0x83*) Origination address is non-ISDN

0x04 (or 0x84*) Call has returned to the ISDN

0x05 (or 0x85*) Interworking has occurred and resulted in
telecomm service change

0x08 (or 0x88*) In-band information or an appropriate
pattern is now available

0x40 (or 0xC0*) SCCP method available

0x60 (or 0xE0*) Pass along method available

0x20 (or 0x60*) Pass along and SCCP available

0xxxxxx Incoming half echo control device not
included

1xxxxxx Incoming half echo control device
included

* when Echo device is included

7

Value[3] Charge Indicator

0x00 No indication

0x01 No charge

0x02 Charge

8

Value[4] Called Party’s Status Indicator

0x00 No indication

0x01 Subscriber free

0x02 Connect when free

9

Value[5] Holding Indicator

0x00 Holding not requested

0x01 Holding requested

10

Value[6] SCCP Method Indicator

0x00 No indication

0x01 Connectionless method available

0x02 Connection oriented method available

0x03 Both connectionless and connection oriented method
available

:

Optional Bytes

For future enhancements in protocol. Also can be used to
customize the protocol with other information with this
packet.