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MLPP Local Handling in ISUP, PRI, and SIP Feature Module

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MLPP Local Handling in ISUP, PRI, and SIP Feature Module

Table Of Contents

MLPP Local Handling in ISUP, PRI, and SIP Feature Module

Feature Description

Benefits

Prerequisites

Restrictions or Limitations

Related Features and Technology

Supported Standards, MIBs, and RFCs

Provisioning Tasks

Provisioning Examples

Provsioning Example of MLPP Local Handling for ISDN

Provsioning Example of MLPP Local Handling for SS7

Provsioning Example of MLPP Local Handling for SIP

Obtaining Documentation and Submitting a Service Request

Glossary


MLPP Local Handling in ISUP, PRI, and SIP Feature Module


Document Release History

Publication Date
Comments

November 14, 2011

Initial release of document.


Feature History

Release
Modification

9.8(1)

The Multilevel Precedence and Preemption (MLPP) Local Handling in ISDN User Part (ISUP), PRI, and Session Initiation Protocol (SIP) feature is introduced on the Cisco PGW 2200 Softswitch software.


This document describes the MLPP Local Handling in ISUP, PRI, and SIP feature.

This feature is described in the following sections:

Feature Description

Supported Standards, MIBs, and RFCs

Provisioning Tasks

Provisioning Examples

Obtaining Documentation and Submitting a Service Request

Glossary

Feature Description

This feature describes the local handling functionalities for MLPP in protocol ISUP, PRI, and SIP. The PGW 2200 Softswitch handles the preemption of calls as the MLLP's supplementary service. A new value, 2, is set to the existing property MlppSupport in order to enable local handling support for MLPP.

Benefits

This feature provides the following benefits:

Enables PGW to maintain MLPP information, such as precedence level, MLPP domain associated with the calls, and so on, in the circuit.

Performs preemptions in case of congestion.

Reserves circuits for reuse.


Note No preemption is done for SIP side based on network resource limitation or user agent busy condition, but the preemption will be done in case of reaching call limit configured for SIP, ISUP and PRI trunk group.


Prerequisites

The Cisco PGW 2200 Softswitch must be running software Release 9.8(1). The prerequisites for Release 9.8(1) can be found in Release Notes for the Cisco PGW 2200 Softswitch Release 9.8(1) at:

http://www.cisco.com/en/US/docs/voice_ip_comm/pgw/9/release/note/rn981.html

Restrictions or Limitations

The MLPP Local Handling in ISUP, PRI, and SIP feature has the following limitations:

Cisco PGW 2200 Softswitch cannot map an MLPP User Indicator that it receives in the Optional Backward Call Indicator (OBCI) Information Element (IE) of an Address Complete Message (ACM) for SIP-to-ISUP calls during preemption.

The preempted circuit cannot be applied in a high-prority preempting call unless the release process from both of the legs is completed in the preempted call.

If preemption fails for any reason, the high-priority preempting call will not look for any free circuit that becomes available during the preemption process, or search for the call in order to preempt again.

MLPP preemption cannot be triggered unless all the possible routes in the route list are exhausted and the cause analysis for internal failures is completed. Preemption cannot be triggered if an external cause is received from the network because external causes have a higher priority than internal causes.

No action will be taken in MLPP local handling when PGW receives a release message with the causes "User Busy" or "No Circuit Available" from the destination exchange.

No particular algorithm is used to select a low-priority call for preemption, but the search process is always start from a priority 4 call and go up to 1 level below the current preempting call priority.

If the preempting call has both the originating and terminating call legs on the same trunk group, the originating bearer channel will be reserved for use in the preempting call.

If switchover occurs before preemption, the MLPP preempting call will not be replicated to the standby PGW before the call replies. In addition, the preempting call will also be lost.

Machine Congestion Level (MCL) and license recjection have higher priority over MLPP calls. A MLLP call can be rejected due to MCL or license rejection. No modification is allowed in PGW handling of calls here.

PGW does not support MLPP local handling in SIP Refer methods.

Related Features and Technology

The following features are related to this feature:

MLPP Relay in PRI to SIP/ISUP Interworking.

MLPP Support for ISUP and SIP Interworking and SIP to SIP Transparency.

Supported Standards, MIBs, and RFCs

This section identifies the new or modified standards, MIBs, and RFCs that are supported by this feature.

Standards

Q.735.3—MLPP for SS7

Q.955.3—MLPP for DSS1

Q.85.1—Stage 2 description for community of interest supplementary services: closed user group

Q.755.1—MTP protocol tester

MIBs

No new or modified MIBs are supported by this feature.

For more information on the MIBs used in the Cisco PGW 2200 Softswitch, see the list of Cisco PGW 2200 Softswitch MIBs at:

http://www.cisco.com/iam/PGW_MIBS/index.html

RFCs

RFC4412—Communications Resource Priority for the Session Initiation Protocol

RFC4411—Extending the SIP Reason Header for preemption Events.

RFC5478—IANA Registration of New Session Initiation Protocol (SIP) Resource-Priority Namespaces

Provisioning Tasks

To use this feature, perform the following provsioning task:

Configure PGW to enable the MLPP local handling support. This means that MlppSupport must be set to 2 on the PRI trunk group, as shown in the following example:

prov-add:trnkgrpprop:name="233", mlppsupport="2"
prov-ed:profile:name="sip-prof1", mlppsupport="2"
prov-ed:profile:name="sip-prof1", mlppnamespace="q735"
prov-add:trnkgrpprop:name="233", mlppni="049"

Provisioning Examples

This section provides provisioning examples pertaining to this feature. You can find additional provisioning examples for the Cisco PGW 2200 Softswitch software in the Cisco PGW 2200 Softswitch Release 9.8 Provisioning Guide, which is available at:

http://www.cisco.com/en/US/docs/voice_ip_comm/pgw/9.8/Provisioning/Guide/prvgde98.html

Table 1 describe PGW behaviors for different configuration conbinations.

Table 1

 

Term Leg

0

1

2

Orig Leg

0

There is no MLPP interworking.

The MLPP information is dropped at orig leg. Therefore, no interworking.

The MLPP information is dropped at orig leg. Therefore, no interworking.

1

MLPP information is not sent to the terminating leg.

There is only MLPP interworking.

There is only MLPP interworking.

2

When sending out a message to the term side, the call will be marked as a non-MLPP call. There is no interworking.

When sending out a message to the term side, the call will be marked as a non-MLPP call. There is no local handling; only interworking works.

Complete local handling is supported. This call can also be preempted.


PGW behaviors for different configuration conbinations

Provsioning Example of MLPP Local Handling for ISDN

The following is a provisioning example of MLPP local handling for ISDN:

prov-sta::srcver="active",dstver="isdn_provision",confirm
prov-add:EXTNODE:NAME="sh-5300-25",DESC="5300-25 for 
MGCP",TYPE="AS5300",ISDNSIGTYPE="N/A",GROUP=0
prov-add:MGCPPATH:NAME="mgcp5300-25",DESC="MGCP sh-5300-1",EXTNODE="sh-5300-25"
prov-add:sigsvcprop:NAME="mgcp5300-25",mgcpDomainNameRemote="S0/DS1-0/1@sh-rusa" 
prov-add:IPLNK:NAME="clink25-1",DESC="MGCP link to 
sh-5300-25",SVC="mgcp5300-25",IPADDR="IP_Addr1",PORT=2427,PEERADDR="10.0.34.103",PEERPORT=
2427,PRI=1,IPROUTE=""
 
   
prov-add:IPFASPATH:NAME="bh25ni2",DESC="NI-2 service to 
AS-5300-25",EXTNODE="sh-5300-25",MDO="ETS_300_172",CUSTGRPID="1111",SIDE="network",ABFLAG=
"n",CRLEN=2
prov-add:SESSIONSET:NAME="gw25set",EXTNODE="sh-5300-25",IPADDR1="IP_Addr1",PEERADDR1="10.0
.34.103",PORT=7007,PEERPORT=7007,TYPE="IPFAS"
prov-add:DCHAN:NAME="ni2dchn1",DESC="IP link-backhaul svc NAS 
5300-25",SVC="bh25ni2",PRI=1,SESSIONSET="gw25set",SIGSLOT=0,SIGPORT=0
 
   
prov-add:TRNKGRP:NAME="888", CLLI="GW-25-NI2", SVC="bh25ni2",TYPE="TDM_PRI"
 
   
*******************MLpp Local Handling**********************************
prov-ed:trnkgrpprop:name="888",custgrpid="1111",mlppsupport="2",mlppni="9004"
******************************************************************************
 
   
prov-add:switchtrnk:name="1", trnkgrpnum="888", span="ffff", cic=1, cu="sh-5300-25", 
spansize=24,endpoint="s0/ds1-0/1@sh-rusa"
prov-add:rttrnkgrp:name="888",type=7,reattempts=3,queuing=0,cutthrough=2,resincperc=0
prov-add:rttrnk:weightedTG="OFF",name="rt888",trnkgrpnum=888
prov-add:rtlist:name="rtlist888",rtname="rt888",distrib="OFF"
 
   
numan-add:resultset:custgrpid="1111",name="pri-888"
numan-add:resulttable:custgrpid="1111",name="result888",resulttype="ROUTE", 
dw1="rtlist888",setname="pri-888"
numan-add:bdigtree:custgrpid="1111",callside="originating",digitstring="888",setname="pri-
888"

Provsioning Example of MLPP Local Handling for SS7

The following is a provisioning example of MLPP local handling for SS7:

prov-sta::srcver="active",dstver="ss7_provision",confirm
;dial plan provision
numan-add:dialplan:custgrpid="1111", OVERDEC="NO"
;stim ss7
prov-add:OPC:NAME="stim-opc",DESC="stim opc",NETADDR="1.1.1",NETIND=2,TYPE="TRUEOPC"
prov-add:DPC:NAME="stim-dpc",DESC="stim dpc",NETADDR="1.2.1",NETIND=2
;provision ss7 link
prov-add:SS7PATH:NAME="ss7path1",DESC="ss7 path to 
stim",MDO="Q761_BASE",CUSTGRPID="1111",SIDE="network",DPC="stim-dpc",OPC="stim-opc",M3UAKE
Y="",ORIGLABEL="",TERMLABEL=""
prov-add:EXTNODE:NAME="stim1",DESC="ss7 stim",TYPE="SLT",ISDNSIGTYPE="N/A",GROUP=0
prov-add:SESSIONSET:NAME="stim-set1",EXTNODE="stim1",IPADDR1="IP_Addr1",PEERADDR1="100.100
.101.151",PORT=7000,PEERPORT=7000,TYPE="BSMV0"
prov-add:LNKSET:NAME="lkset1",DESC="ss7 linkset to 
stim",APC="stim-dpc",PROTO="SS7-ITU",TYPE="IP"
prov-add:SS7ROUTE:NAME="ss7rt1",DESC="ss7 route to 
stim",OPC="stim-opc",DPC="stim-dpc",LNKSET="lkset1",PRI=1
prov-add:C7IPLNK:NAME="c7lnk1",DESC="ss7 link to 
stim",LNKSET="lkset1",SLC=0,PRI=1,TIMESLOT=0,SESSIONSET="stim-set1"
 
   
;provision mgcp path
prov-add:EXTNODE:NAME="mgcp1",DESC="mgcp stim",TYPE="AS5300",ISDNSIGTYPE="N/A",GROUP=0
prov-add:MGCPPATH:NAME="stimpath1",DESC="mgcp path to pype",EXTNODE="mgcp1"
prov-add:IPLNK:NAME="stim-iplnk1",DESC="mgcp to 
pype",SVC="stimpath1",IPADDR="IP_Addr1",PORT=2427,PEERADDR="10.0.251.126",PEERPORT=2427,PR
I=1,IPROUTE=""
 
   
;provision trunk grp
prov-add:trnkgrp:name="233", svc="ss7path1",type="TDM_ISUP",SELSEQ="LIDL"
prov-ed:trnkgrpprop:name="233",custgrpid="1111"
***************************MLpp Local Handling************************************
 
   
prov-ed:trnkgrpprop:name="233",mlppsupport="2",mlppni="049"
 
   
*********************************************************************************
prov-add:switchtrnk:name="1",trnkgrpnum="233",span="ffff",cic=1,cu="mgcp1",spansize=31,end
point="s0/ds1-1/1@aristim2"
prov-add:rttrnkgrp:name="233",type=1,reattempts=1,queuing=0,cutthrough=0,resincperc=0
prov-add:rttrnk:weightedTG="OFF",name="rt233",trnkgrpnum=233
prov-add:rtlist:name="rtlst233",rtname="rt233",distrib="OFF"
;add digitstring to routeset
numan-add:resultset:custgrpid="1111",name="rset233"
numan-add:resulttable:custgrpid="1111",name="rtab1",resulttype="ROUTE",dw1="rtlst233",setn
ame="rset233"
numan-add:bdigtree:custgrpid="1111",callside="originating",digitstring="232",setname="rset
233"
 
   
 
   
;active config
prov-cpy
;change status to in service
set-c7lnk:c7lnk1:is
set-iplnk:stim-iplnk1:is
 
   
 
   
a.isup_send_iam(opc=a.opc,dpc=a.dpc,cic=1,called='2320001',calling='12345678',link=0)

Provsioning Example of MLPP Local Handling for SIP

The following is a provisioning example of MLPP local handling for SIP:

prov-sta::srcver="new",dstver="MLpp",confirm
numan-add:dialplan:CUSTGRPID="1111", OVERDEC="NO"
prov-add:SIPPATH:NAME="sip-path",DESC="SIPsigpath",MDO="IETF_SIP",ORIGLABEL="",TERMLABEL="
"
prov-add:SIPLNK:NAME="sip-link1",DESC="SIPlink",SVC="sip-path",IPADDR="IP_Addr1",PORT=5060
,PRI=1
prov-add:trnkgrp:NAME="100", CLLI="sipin-path", SVC="sip-path", 
TYPE="SIP_IN",SELSEQ="LIDL", QABLE="N"
prov-add:TRNKGRP:NAME="235", CLLI="sip-path", SVC="sip-path", TYPE="IP_SIP", 
SELSEQ="LIDL", QABLE="N"
prov-add:profile:name="sip-prof1",type="SIPPROFILE",custgrpid="1111",mgcdomain="10.0.49.25
0"
prov-add:trnkgrpprof:name="100",profile="sip-prof1"
prov-add:profile:name="sip-prof2",type="SIPPROFILE",custgrpid="1111",mgcdomain="10.0.49.25
0"
prov-add:trnkgrpprof:name="235",profile="sip-prof2"
*************************MLPP Local 
Handling*************************************************************
prov-ed:profile:name="sip-prof2",mlppsupport="2",mlppnamespace="q735"
;to set call limit to desired value
prov-add:loclabel:name="sip235",calllimit=2   
;attach call limit to trunkgroup
prov-ed:trnkgrp:name="235",origlabel="sip235",termlabel="sip235" 
set-callim:enable:  ; enable call limiting
******************************************************************************************
*****************
 
   
prov-add:siprttrnkgrp:name="235",url="10.0.174.206",srvrr=0,sipproxyport=5060,version="2.0
",cutthrough=1,extsupport=1
prov-add:rttrnk:weightedTG="OFF",name="rg235",trnkgrpnum=235
prov-add:rtlist:name="rlst235",rtname="rg235",distrib="OFF"
numan-add:resultset:custgrpid="1111",name="rset235"
numan-add:resulttable:custgrpid="1111",name="rtab235",resulttype="ROUTE",dw1="rlst235",set
name="rset235"
numan-add:bdigtree:custgrpid="1111",callside="originating",digitstring="235",setname="rset
235"
prov-cpy:

Obtaining Documentation and Submitting a Service Request

For information on obtaining documentation, submitting a service request, and gathering additional information, see the monthly What's New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation, at:

http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html

Subscribe to the What's New in Cisco Product Documentation as a Really Simple Syndication (RSS) feed and set content to be delivered directly to your desktop using a reader application. The RSS feeds are a free service and Cisco currently supports RSS Version 2.0.

Glossary

Table 2 provides a list of acronyms used in this document, and their expansions.

Table 2 Expansions

Acronym
Expansion

ISDN

Integrated Services Digital Network

ISUP

ISDN User Part

LFB

Look Ahead for Busy

MCL

Machine Congestion Level

MLPP

Multilevel Precedence and Preemption

PGW

PSTN Gateway

PRI

Primary Rate Interface

PSTN

Public Switched Telephony Network

SIP

Session Initiation Protocol