Lucent Technologies DEFINITY Enterprise Communications Server Release 5, CallVisor, ASAI Protocol Reference Instructions Manual

Management Information Message (MIM)
Issue 6 June 1997
3-3
Management Information Message 
(MIM)
This message is currently used in ASAI only to enable and disable the ECS 
alarming of an ASAI link. This document contains only the necessary subset of 
the MIM and its related procedures. See the 
ISDN Basic Rate Interface (BRI) 
Specification
 for a complete discussion. The MIM carries only the global CRV on 
an ASAI link.
Message type: Management Information Message (MIM)
Direction: both
REGister Message...

Message Descriptions
3-4Issue 6 June 1997 
RELease COMplete Message
The RELease COMplete message ends an ASAI association.   The sending and 
receiving endpoints release the CRV.
Message type: RELease COMplete
Direction: both
RESTart Message
The RESTart message may be sent from either side of the ASAI interface to 
request the recipient to restart the ASAI interface. The sending endpoint clears all 
ASAI associations in progress on the interface and expects the receiving endpoint 
to do the same and then...

RESTart Message
Issue 6 June 1997
3-5
Message type: RESTart
Direction: both
Table 3-6. RESTart Message Content
Information Element Direction Type Length
Protocol discriminator both M 1
Call reference both M 2-3
Message type both M 1
Restart Indicator both M 3
Locking Shift to Code Set 6 both 0 1
Version IE both O 3-7
(multiple IEs allowed) 

Message Descriptions
3-6Issue 6 June 1997 
RESTart ACKnowledge Message
The RESTart ACKnowledge message acknowledges the receipt of the RESTart 
message and signifies that the requested restart of the ASAI interface is 
complete.
Although in the 
ISDN Basic Rate Interface (BRI) Specification this is an optional 
message in the terminal-to-ECS direction, adjunct support of this message is 
mandatory in that direction on an ASAI.
NOTE:
The Call Reference Value is encoded as the Global CRV, and the Restart...

Status Message
Issue 6 June 1997
3-7
Status Message
The STATUS message is included here for completeness. Certain BRI (hence 
ASAI) implementations may send STATUS in response to protocol errors. 
Although the ECS does not transmit STATUS messages, the ECS recognizes 
incoming STATUS messages as valid messages and does not treat them as ASAI 
protocol errors. The ECS ignores incoming STATUS messages; there is no 
response.
Message type: STATUS
Direction: both
Table 3-8. STATUS Message Content
Information...

Message Descriptions
3-8Issue 6 June 1997  

Issue 6  June 19974-1
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Information Elements
This chapter describes the element structure (information element) of the layer 3 
protocol messages.
Every message contains a grouping of the following information elements (IEs):
nThe BRI protocol discriminator
nCall Reference Value (CRV)
nMessage type
nMandatory information elements, as required
nAdditional information elements, when required
The first three elements are common to all the messages and must always be 
present, while the last two elements are...

Information Elements
4-2Issue 6  June 1997 
Figure 4-1. General Message Organization Example
Unless specified otherwise, a particular information element may be present only 
once in a given message.
The term default means the default value defined is used in the absence of any 
assignment or negotiation of alternate values.
Because an information element may occur several times in a message, the 
ordering of the instances of the information element is important. Chapter 5, ‘‘Byte 
Level Messages’’...

Protocol Discriminator
Issue 6  June 1997
4-3
value of the “length of IE contents” for the Facility IE that gives a 260-byte 
message is shown in the following table:
Protocol Discriminator
 The BRI protocol discriminator is 0x08, “0 0 0 0 1 0 0 0.”
Call Reference Value (CRV)
ISDN CRVs are unique at an ASAI interface and are present in every ASAI 
message that passes across the interface. ASAI endpoints use the CRV to 
associate a sequence of messages that comprise an ASAI association.
The originating...

Information Elements
4-4Issue 6  June 1997 
Figure 4-2. ISDN Call Reference Value
The CRV has three fields:
nThe length of the CRV
nThe call reference value
nThe call reference flag
The CRV length is the number of bytes that follow the byte containing the length, 
so the length may take on the values “0 0 0 1” (one byte follows), or “0 0 1 0” (two 
bytes follow). Each ASAI interface is administered individually for one- or two-byte 
CRV lengths.
The Global Call Reference value is a CRV with length 1 or 2...