AudioCodes Mediant 1000B User Manual page 448

The device automatically interworks the network identity digits (NI) in the ISDN Q.931
Precedence Information Element (IE) to the network domain subfield of the INVITE's
Resource-Priority header, and vice versa. The SIP Resource-Priority header contains two
fields, namespace and priority. The namespace is subdivided into two subfields, network-
domain and precedence-domain. Below is an example of a Resource-Priority header
whose network-domain subfield is "uc", r-priority field is "priority" (2), and precedence-
domain subfield is "000000":
Resource-Priority: uc-000000.2
The MLPP Q.931 Setup message contains the Precedence IE. The NI digits are presented
by four nibbles found in octets 5 and 6. The device checks the NI digits according to the
translation table of the Department of Defense (DoD) Unified Capabilities (UC)
Requirements (UCR 2008, Changes 3) document, as shown below:
Level IE
0000
0001
0002
0003
Notes:
•
If the received ISDN message contains NI digits that are not listed in the
translation table, the device sets the network-domain to "uc" in the outgoing SIP
message.
•
If the received SIP message contains a network-domain value that is not listed in
the translation table, the device sets the NI digits to "0000" in the outgoing ISDN
message.
•
If the received ISDN message does not contain a Precedence IE, you can
configure the namespace value - dsn (default), dod, drsn, uc, or cuc - in the SIP
Resource-Priority header of the outgoing INVITE message. This is done using the
MLPPDefaultNamespace parameter. You can also configure up to 32 user-defined
namespaces, using the table ini file parameter, ResourcePriorityNetworkDomains.
Once defined, you need to set the MLPPDefaultNamespace parameter value to
the desired table row index.
By default, the device maps the received Resource-Priority field of the SIP Resource-
Priority header to the outgoing ISDN PRI Precedence Level (priority level) field as follows:

If the network-domain field in the Resource-Priority header is "uc", then the device
sets the Precedence Level field in the ISDN PRI Precedence Level IE according to
Table 5.3.2.12-4 (Mapping of RPH r-priority Field to PRI Precedence Level Value):
Table 26-9: Mapping of SIP Resource-Priority Header to PRI Precedence Level for MLPP
MLPP Precedence Level
Routine
Priority
Immediate
Flash
Flash Override
User's Manual
Table 26-8: NI Digits in ISDN Precedence
Network Domain in SIP Resource-Priority Header
PRI Precedence Level
4
3
2
1
0
448
Mediant 1000B Gateway & SBC
uc
cuc
dod
nato
SIP Resource-Priority Header Field
0
2
4
6
8
Document #: LTRT-27034