Troubleshooting IP Telephony Networks Part 1

Transcription

1 1 Troubleshooting IP Telephony Networks Part 1 Session Copyright Printed in USA. 2

2 Session Objectives Understand the functionality of call flows, from the perspective of Cisco CallManager when all works well understand the trace outputs and provide a troubleshooting methodology To be able to enable the debugs and provide the information requested by Cisco TAC in resolving your issues 3 Session Objectives Troubleshooting Or the art of knowing how things work when all is functioning properly, so we can identify and focus on the abnormal behavior Describe a few core scenarios with much detail Cannot be an in-depth discussion of all possible trouble scenarios Please ask questions; We may need to discuss some items off-line to allow the presentation to flow in the allotted time 4 Copyright Printed in USA.

3 What You Should Know CCM configuration and operation Cisco IOS GW configuration and operation Basic understanding of: Skinny Client Control Protocol (SCCP) Media Gateway Control Protocol (MGCP) 5 What You Should Know Basic understanding of H.323 signaling and control RAS (Registration, Admission, Status) H.225 call control H.245 media control 6 Copyright Printed in USA.

4 Agenda Phone Initialization Tools and Utilities to Configure, Monitor and Troubleshoot CCM IP Telephony Case Study and Troubleshooting Techniques 7 IP Phone Initialization Inline Power Modified FLP (Fast Link Pulse) Return FLP Catalyst Switch Inline Power MAC: C3AD7E CDP (I Need 6.3 W) Phone: Mute, Headset, Speaker Buttons Illuminated 8 Copyright Printed in USA.

5 IP Phone Initialization AUX VLAN FLP CDP (VLAN Number) Catalyst Switch MAC: C3AD7E Phone Displays: Configuring VLAN Check Settings: NetCfg->19 Operational VLAN ID 9 IP Phone Initialization IP Configuration MAC: C3AD7E CDP DHCP Req DHCP Rsp (IP Add, Def-GW, TFTP, DNS*) Catalyst Switch DHCP Server Phone Displays: Configuring IP *DNS is Optional Check settings: NetCfg-> 1 DHCP Server NetCfg-> 6 IP Address 10 Copyright Printed in USA.

6 IP Phone Initialization TFTP MAC: C3AD7E CDP DHCP Req DHCP Rsp (IP Add, Def-GW, TFTP, DNS*) TFTP Read TFTP Data (OS79XX.txt) TFTP Read TFTP Data (SEP003094C3AD7E.cnf.xml) Catalyst Switch DHCP Server TFTP Server Phone Displays: Configuring IP Error Verifying Config Info Check settings: NetCfg-> 8 TFTP Server 11 IP Phone Initialization TFTP Trace TFTP traces provide more information on initialization process TFTP [opcode = 1] [Mode = octet] [thread count 0] <CLID::StandAloneCluster> <NID:: ><CT::3456: :50953><IP:: > <DEV::SEP003094C25FCE.cnf.xml> TFTP file error[file Name or path not found 2] <CLID::StandAloneCluster> <NID:: ><CT::3456: :50953><IP:: > <DEV::SEP003094C25FCE.cnf.xml> Note that the phone requests the configuration file SEP0002FDAEFB9D.cnf.xml from the CallManager (version 3.1 and above) Phone Loads in CallManager Releases prior to 3.1 request the File name: SEP0002FDAEFB9D.cnf will understand both file formats Files served by TFTP Are located in c:\program Files\Cisco\TFTPPath CCM 3.2: By default SEP.cnf.xml files cached in RAM and not written to disk 12 Copyright Printed in USA.

7 IP Phone Initialization DNS MAC: C3AD7E CDP DHCP TFTP (CCM1 = SJSUB1) DNS Request (SJSUB1 = IP?) DNS Response (SJSUB1 = x.x.x.x) Catalyst Switch DHCP Server TFTP Server DNS Server Phone displays: Configuring IP CallManager Name DNS Error Defaulting CM to TFTP Server Check settings: NetCfg-> 14 DNS Server 1 13 IP Phone Initialization CCM Registration MAC: C3AD7E CDP DHCP TFTP DNS Skinny Register Skinny Registration Confirm Catalyst Switch DHCP Server TFTP Server DNS Server Call Manager Phone displays: Configuring CM List Registration Rejected Opening CM Down, Features Disabled Check settings: NetCfg-> 21 Call Manager 1 14 Copyright Printed in USA.

8 Post Initialization The Sound of Success Reorder! Fast busy! Registered Re-order or fast busy is NOT a phone problem No route for dialed destination on CCM No matching route patterns on GW CODEC mismatch More on this in Troubleshooting IP Telephony Networks II 15 Agenda Phone Initialization Tools and Utilities to Configure, Monitor and Troubleshoot CCM IP Telephony Case Study and Troubleshooting Techniques 16 Copyright Printed in USA.

9 Tools and Utilities to Configure, Monitor and Troubleshoot on CallManager CCM administration Event log CCM serviceability Performance monitor Trace configuration CCM traces Collection Q931 translator 17 EventLog Start-> Programs-> Administrative Tools -> Event Viewer -> Application Log EventLog is a Windows 2000 Server application that displays a log of Windows 2000 server and CCM Even if a service (including TFTP) can not read the database (where it gets trace configuration), it will add errors to the event log 18 Copyright Printed in USA.

10 EventLog 19 Enabling Tracing in Cisco CallManager Make sure the SDL trace level is set properly 0xA000EB15 gives the best results; default (pre-3.3) is 0xA000CB15 This SDL setting adds additional detail in the CCM traces SDL traces are not useful for most troubleshooting, however if a problem needs to be escalated to development engineering, SDL traces are usually a requirement 20 Copyright Printed in USA.

11 CCM Trace: To Get the Most Detail Service Service Parameter Service = Cisco CallManager 21 Enabling Tracing in Cisco CallManager For nearly all troubleshooting scenarios, you will need traces from the Cisco CallManager service; click the Set Default button then change the trace level to either Arbitrary or Detailed Arbitrary and Detailed are nearly identical, except Detailed shows KeepAlives and some additional digit analysis data CCM trace (a.k.a.: System diagnostic interface) files provide the greatest level of detail 22 Copyright Printed in USA.

12 Trace Utility Node, Service Selection Select the Node Select the Service on Which Trace Needs to Be Enabled 23 Enabling Tracing in Cisco CallManager Click the Update Button to Save the Settings Updates All CallManagers in this Cluster with these Settings 24 Copyright Printed in USA.

13 Trace Utility Debug Trace Level Error Used for all traces generated in abnormal path; minimum amount of CPU cycles Special Non-repetitive messages; ex. all system and device initialization messages State transition Call processing events Significant Media layer events Arbitrary Used for debugging excluding keepalives Detail Detailed debug information 25 Trace Utility SDI Trace Format, raw We Are Going to Detail this Entry from the raw Trace File Output; Please Note that in this View, Word Wrap Is Turned on 26 Copyright Printed in USA.

14 Trace Utility SDI Trace Format, detailed 03/20/ :17:54.553Cisco CallManager StationInit: 51b7af4 OffHook. <CLID::WWCCM1-Cluster> <NID:: > <CT::1,100,95, > <IP:: > <DEV::SEP0002FDAEFB9D> Field Name Date Time System Trace Text Cluster ID (CLID) Node ID (NID) Correlation Tag (CT) Source Device Tag Mapping Example 03/20/ :17: Cisco CallManager Trace/Event ID, Event Information WWCCM1-Cluster ,100,95, , SEP0002FDAEFB9D Destination Device Name, DN, Application defined Tags Not used in this example Device ID a.k.a. TCP Handle 27 How Do We Find Information in these Huge Text Files? We need a place to start, a hook E.g.: MAC address of the phone Scour the trace files for occurrences of that hook Focus our search around the time of the event we are investigating E.g.: Look for the Device ID (TCP handle) This tag gets changed if the phone has to re-establish its TCP connection with the CallManager (e.g.: phone reboot) 28 Copyright Printed in USA.

15 How Do We Find Information in these Huge Text Files? Findstr is a Windows-bundled utility (functions similarly to grep) Findstr /? will provide instructions on how to use Example: E:\>findstr "SEPABCDEFB8931F" ccm*.txt Finds all instances of the mac address SEPABCDEFB8931F in all files named ccm*.txt in the E drive This will let us identify the TCP handle (device ID) for that phone 29 How Do We Find Information in these Huge Text Files? Now We Know what the Device ID Is for that Phone and Can Chase All Traces Pertaining to that Phone Only; Scenarios of what to Look for Will Be More Obvious as We Review the Case Studies 30 Copyright Printed in USA.

16 Agenda Phone Initialization Tools and Utilities to Configure, Monitor and Troubleshoot CCM IP Telephony Case Study and Troubleshooting Techniques 31 IP Telephony Case Study and Troubleshooting Techniques Case study # 1 IP phone to IP phone Intra-cluster call (successful) Case study # 2 IP phone to IP phone Intra-cluster call (failed) Case study # 3 IP phone to MGCP gateway Case study #4 IP phone to H.323 gateway (with GateKeeper) 32 Copyright Printed in USA.

17 Case Study #1: IP Phone to IP Phone Intra-Cluster (Successful Call) IP phone to IP phone call flow within a cluster IP phone to IP phone call flow SCCP messages IP phone registration and call flow messages through the CCM traces 33 IP-Phone to IP-Phone Call Flow Phone A is registered to CallManager X 2 E.164 Lookup CallManager Cluster 1 CallManager X CallManager Y Phone B is registered to CallManager X Call is placed from Phone A (1000) to Phone B (1006) Phone A 6 Connect RTP Stream Call Setup Phone B Ringback Call Setup Ring Offhook 34 Copyright Printed in USA.

18 IP-Phone to IP-Phone Call Flow Very important note All traces were generated on CallManager X, since both phones are registered to it If phone B were registered to CallManager Y, we would have to collect traces from both servers Phone A E.164 Lookup 6 Connect RTP Stream Call Setup Phone B CallManager Cluster 1 CallManager X Ringback Call Setup Ring Offhook CallManager Y 35 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) This Message Gone in CCM 3.3 Station Call Information Station Call Info Station Start Tone (alerting) Station Stop Tone Station Open Receive Channel Station Call Info Station Start Media Transmission Station Open Receive Channel AcK Station On Hook Station Set Lamp (Off) Station Close Receive Channel Station Stop Media Transmission Conversation Station Set Lamp (Blink) Station Set Ringer (On) Station Off Hook Station Set Lamp (Steady) Station Set Ringer (Off) Station Open Receive Channel Station Open Receive Channel Ack Station Start Media Transmission Station Close Receive Channel Station Stop Media Transmission Station Set Lamp (Off) Station On Hook 36 Copyright Printed in USA.

19 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook 37 Intra Cluster Call Flow Trace Phone Goes Off Hook Phone 1000 goes to OffHook 03/20/ :14: Cisco CallManager StationInit: c OffHook. <CLID::WWCCM1- Cluster><NID:: ><CT::1,100,95,1.1243><IP:: ><DEV::SEP0002FD AEFB9D> Header that is common to all the messages 03/20/ :14: Cisco CallManager Trailer is common to all the messages to and from this phone <CLID::WWCCM1- Cluster><NID:: ><CT::1,100,95,1.1243><IP:: ><DEV::SEP0002FD AEFB9D> Header and trailer messages will be omitted from now on to simplify the display The c is unique ID for this phone StationInit indicates that CallManager received a TCP message from a skinny station 38 Copyright Printed in USA.

20 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text 39 Intra Cluster Call Flow Trace Send Messages to the Phone CallManager sends message to prompt the text message Enter Number on the phone & changes the softkeys on the phone Locations: reserve: cdccpid=( ) Orig=Dest=0 no need to reserve bw. StationD: c DisplayText text=' 1000 (Not sent in CCM 3.3) StationD: c SetLamp stimulus=9(line) stimulusinstance=1 lampmode=2(lampon). StationD: c CallState callstate=1(offhook) lineinstance=1 callreference= StationD: c DisplayPromptStatus timeoutvalue=0 promptstatus='enter number' lineinstance=1 callreference= StationD: c SelectSoftKeys instance=1 reference= softkeysetindex=4 validkeymask=-1. StationD: c ActivateCallPlane lineinstance=1. StationD indicates that CallManager is sending a message to the Skinny station lineinstance=1 means line 1 of the phone For a Skinny call, each endpoint in a call is assigned a callreference, so for a two-way conversation, you will have two callreferences 40 Copyright Printed in USA.

21 Intra Cluster Call Flow Trace SCCP Call States 1 Off Hook 2 On Hook 3 Ring Out 4 Ring In 5 Connected 6 Busy 7 Congestion 8 Hold 9 Call Waiting 10 Call Transfer 11 Call Park 12 Proceed 13 Call Remote Multiline 14 Invalid Number 41 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) 42 Copyright Printed in USA.

22 Intra Cluster Call Flow Trace Start Dial Tone CallManager begins routing process; Current set of dialed digits is empty; Every route pattern in the table is a potential match at this time (These messages are internal routing process within the CallManager, not sent to the phones) Insert an entry into CiCcp table, now this table has 1 entries Insert an entry into CiCcp table, now this table has 2 entries Digit analysis: match(fqcn="1000", cn="1000", pss="pa:employee:cer", dd="") Digit analysis: potentialmatches=potentialmatchesexist CallManager triggers the dial tone on the phone StationD: c StartTone tone=33(insidedialtone). CallManager sets lamp state StationD: c SetLamp stimulus=9(line) stimulusinstance=1 lampmode=2(lampon). fqcn = Fully Qualified Calling Party Number cn = Calling Party Number pss = Partition Search Space (The Ordered List of Partitions that Make up the Calling Search Space for This Device and Line) dd = Dialed Digits 43 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) 44 Copyright Printed in USA.

23 Intra Cluster Call Flow Trace Dialing Starts User starts entering the digits First digit 1 is dialed StationInit: c KeypadButton kpbutton=1. CallManager stops sending the dial tone to the phone 1000 and collects the other digits entered through the keypad (We dialed 1006) StationD: c StopTone. StationD: c SelectSoftKeys instance=1 reference= softkeysetindex=6 validkeymask=-1. Digit analysis: match(fqcn="1000", cn="1000", pss="pa:employee:cer", dd="1") Digit analysis: potentialmatches=potentialmatchesexist StationInit: c KeypadButton kpbutton=0. Digit analysis: match(fqcn="1000", cn="1000", pss="pa:employee:cer", dd="10") Digit analysis: potentialmatches=potentialmatchesexist StationInit: c KeypadButton kpbutton=0. Digit analysis: match(fqcn="1000", cn="1000", pss="pa:employee:cer", dd="100") Digit analysis: potentialmatches=potentialmatchesexist StationInit: c KeypadButton kpbutton=6. Digit analysis: match(fqcn="1000", cn="1000", pss="pa:employee:cer", dd="1006") 45 Intra Cluster Call Flow Trace Digit Analysis A match was found: Here are the CallManager digit analysis results Digit analysis: analysis results PretransformCallingPartyNumber=1000 CallingPartyNumber=1000 DialingPartition=Employee DialingPattern=1006 DialingRoutePatternRegularExpression=(1006) DialingWhere= PatternType=Enterprise PotentialMatches=NoPotentialMatchesExist * DialingSdlProcessId=(1,34,20) PretransformDigitString=1006 * NoPotentialmatchesExist Means that the Dialed String Is Not Partially Matching a Pattern within this Call s pss 46 Copyright Printed in USA.

24 Intra Cluster Call Flow Trace Digit Analysis Digit analysis results Continued PretransformTagsList=SUBSCRIBER PretransformPositionalMatchList=1006 CollectedDigits=1006 UnconsumedDigits= TagsList=SUBSCRIBER PositionalMatchList=1006 Voic box=1006 DisplayName= Luc Bouchard RouteBlockFlag=RouteThisPattern InterceptPartition=Employee InterceptPattern=1006 InterceptWhere= InterceptSdlProcessId=(1,25,1) InterceptSsType= InterceptSsKey=16 47 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Station Call Info Station Start Tone (Alerting) Station Call Information Station Set Lamp (Blink) Station Set Ringer (On) 48 Copyright Printed in USA.

25 Intra Cluster Call Flow Trace Called Party Gets Notified CallManager sends the Call state information to indicate an incoming call on called party phone StationD: 52044a0 DisplayText text=' 1006 '. StationD: 52044a0 CallState callstate=4(ringin) lineinstance=1 callreference= CallManager sending the calling party information to the called phone StationD: 52044a0 CalInfo callingpartyname='ramesh Kaza' callingparty=1000 cgpnvoic box=1000 calledpartyname='luc Bouchard' calledparty=1006 cdpnvoic box=1006 originalcalledpartyname='luc Bouchard' originalcalledparty=1006 originalcdpnvoic box=1006 originalcdpnredirectreason=0 lastredirectingpartyname='luc Bouchard' lastredirectingparty=1006 lastredirectingvoic box=1006 lastredirectingreason=0 calltype=1(inbound) lineinstance=1 callreference= CallManager sending the signal to the called party phone to blink the lamp StationD: 52044a0 SetLamp stimulus=9(line) stimulusinstance=1 lampmode=5(lampblink). CallManager instructs phone B to ring StationD: 52044a0 SetRinger ringmode=2(insidering). Send the alerting tone (Ring back) to the calling phone StationD: c StartTone tone=36(alertingtone). We Are Not Showing the Station Call Info Sent to the Calling Phone (Not Sent in CCM 3.3) 49 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Station Call Info Station Start Tone (Alerting) Station Stop Tone Station Call Information Station Set Lamp (Blink) Station Set Ringer (On) Station Off Hook Station Set Lamp (Steady) Station Set Ringer (Off) 50 Copyright Printed in USA.

26 Intra Cluster Call Flow Trace Called Party Answers CallManager received an OffHook message from the called party phone (1006); Note that the IP address and it s MAC address are shown in the traces StationInit: 52044a0 OffHook. <CLID::WWCCM1- Cluster><NID:: ><CT::1,100,95,1.1248><IP:: ><DEV::SEP00036B5 4BD01> StationD: 52044a0 ClearNotify. CallManager notifies called phone to stop the ring tone StationD: 52044a0 SetRinger ringmode=1(ringoff). Set the lamp on the called party phone to a steady state and update the CallState StationD: 52044a0 SetLamp stimulus=9(line) stimulusinstance=1 lampmode=2(lampon). StationD: 52044a0 CallState callstate=1(offhook) lineinstance=1 callreference= StationD: 52044a0 ActivateCallPlane lineinstance=1. Instruct calling party phone to stop the ring back tone StationD: c StopTone. 51 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Station Call Info Station Start Tone (Alerting) Station Stop Tone Station Open Receive Channel Station Call Information Station Set Lamp (Blink) Station Set Ringer (On) Station Off Hook Station Set Lamp (Steady) Station Set Ringer (Off) Station Open Receive Channel 52 Copyright Printed in USA.

27 Intra-Cluster Call Flow Trace Audio Connect Time Streaming messages, CallManager asks the phones to give the RTP address from the phones StationD: c OpenReceiveChannel conferenceid=0 passthrupartyid=177 millisecondpacketsize=20 compressiontype=4(media_payload_g711ulaw64k) qualifierin=?. myip: 46a8110a ( ) StationD: 52044a0 StopTone. StationD: 52044a0 OpenReceiveChannel conferenceid=0 passthrupartyid=193 millisecondpacketsize=20 compressiontype=4(media_payload_g711ulaw64k) qualifierin=?. myip: 4ba8110a ( ) 53 Intra-Cluster Call Flow Trace Hex to Dotted Decimal Conversion Some messages in CCM traces represent IP addresses in hex; To convert the hex to IP address, first take each octet of the IP address starting from the end 0x4ba8110a > 0A 11 A8 4B Then convert each piece to decimal: 0A = = 17 A8 = 168 4B = 75 So the IP address is Copyright Printed in USA.

28 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Station Call Info Station Start Tone (Alerting) Station Stop Tone Station Open Receive Channel Station Start Media Transmission Station Call Information Station Set Lamp (Blink) Station Set Ringer (On) Station Off Hook Station Set Lamp (Steady) Station Set Ringer (Off) Station Open Receive Channel Station Open Receive Channel Ack 55 Intra-Cluster Call Flow Trace Audio Connect Time Called party phone responds first StationInit: 52044a0 OpenReceiveChannelAck Status=0, IpAddr=0x4ba8110a, Port=31016, PartyID=193 Tell the calling party phone to start talking to called party s RTP address, at this point called party can hear calling party StationD: c StartMediaTransmission conferenceid=0 passthrupartyid=193 remoteipaddress=4ba8110a( ) remoteportnumber=31016 millisecondpacketsize=20 compresstype=4(media_payload_g711ulaw64k) qualifierout=?. myip: 46a8110a ( ) 56 Copyright Printed in USA.

29 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Station Call Info Station Start Tone (Alerting) Station Stop Tone Station Open Receive Channel Station Start Media Transmission Station Open Receive Channel AcK Station Call Information Station Set Lamp (Blink) Station Set Ringer (On) Station Off Hook Station Set Lamp (Steady) Station Set Ringer (Off) Station Open Receive Channel Station Open Receive Channel Ack Station Start Media Transmission 57 Intra Cluster Call Flow Trace Audio Connect Time Calling party responds with the RTP details StationInit: c OpenReceiveChannelAck Status=0, IpAddr=0x46a8110a, Port=28052, PartyID=177 Inform called party about the calling party s RTP information StationD: 52044a0 StartMediaTransmission conferenceid=0 passthrupartyid=193 remoteipaddress=46a8110a( ) remoteportnumber=28052 millisecondpacketsize=20 compresstype=4(media_payload_g711ulaw64k) qualifierout=?. myip: 4ba8110a ( ) 58 Copyright Printed in USA.

30 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Station Call Info Station Start Tone (Alerting) Station Stop Tone Station Open Receive Channel Station Start Media Transmission Station Open Receive Channel AcK Station On Hook Station Set Lamp (Off) Conversation Station Call Information Station Set Lamp (Blink) Station Set Ringer (On) Station Off Hook Station Set Lamp (Steady) Station Set Ringer (Off) Station Open Receive Channel Station Open Receive Channel Ack Station Start Media Transmission 59 Intra-Cluster Call Flow Trace Calling Party Disconnects OK enough talk for now, calling party phone goes onhook StationInit: c OnHook. StationD: c SetSpeakerMode speakermode=2(off). StationD: c ClearPromptStatus lineinstance=1 callreference= StationD: c CallState callstate=2(onhook) lineinstance=1 callreference= StationD: c SelectSoftKeys instance=0 reference=0 softkeysetindex=0 validkeymask=7. StationD: c DisplayPromptStatus timeoutvalue=0 promptstatus='your current options' lineinstance=0 callreference=0. StationD: c ActivateCallPlane lineinstance=0. StationD: c SetLamp stimulus=9(line) stimulusinstance=1 lampmode=1(lampoff). StationD: c DefineTimeDate timedateinfo=? systemtime= StationD: c StopTone. 60 Copyright Printed in USA.

31 Simple Intra-Cluster Call Flow (SCCP) IP Phone A CCM IP Phone B Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Station Call Info Station Start Tone (Alerting) Station Stop Tone Station Open Receive Channel Station Start Media Transmission Station Open Receive Channel AcK Station On Hook Station Set Lamp (Off) Station Close Receive Channel Station Stop Media Transmission Conversation Station Call Information Station Set Lamp (Blink) Station Set Ringer (On) Station Off Hook Station Set Lamp (Steady) Station Set Ringer (Off) Station Open Receive Channel Station Open Receive Channel Ack Station Start Media Transmission Station Close Receive Channel Station Stop Media Transmission 61 Intra Cluster Call Flow Trace Audio Disconnect Process CallManager instructs phones to close the media channel and stop the media transmission StationD: c CloseReceiveChannel conferenceid=0 passthrupartyid=177. myip: 46a8110a ( ) StationD: c StopMediaTransmission conferenceid=0 passthrupartyid=177. myip: 46a8110a ( ) StationD: 52044a0 CloseReceiveChannel conferenceid=0 passthrupartyid=193. myip: 4ba8110a ( ) StationD: 52044a0 StopMediaTransmission conferenceid=0 passthrupartyid=193. myip: 4ba8110a ( ) 62 Copyright Printed in USA.

32 Simple Intra-Cluster Call Flow (SCCP) IP Phone CCM IP Phone Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Station Call Info Station Start Tone (Alerting) Station Stop Tone Station Open Receive Channel Station Start Media Transmission Station Open Receive Channel AcK Station On Hook Station Set Lamp (Off) Station Close Receive Channel Station Stop Media Transmission Conversation Station Call Information Station Set Lamp (Blink) Station Set Ringer (On) Station Off Hook Station Set Lamp (Steady) Station Set Ringer (Off) Station Open Receive Channel Station Open Receive Channel Ack Station Start Media Transmission Station Close Receive Channel Station Stop Media Transmission Station Set Lamp (Off) Station On Hook 63 Intra Cluster Call Flow Trace Audio Disconnect Process CallManager updates the status of the called party phone to offhook and changes the prompt status on the Phone StationD: 52044a0 DefineTimeDate timedateinfo=? systemtime= StationD: 52044a0 SetSpeakerMode speakermode=2(off). StationD: 52044a0 ClearPromptStatus lineinstance=1 callreference= StationD: 52044a0 CallState callstate=2(onhook) lineinstance=1 callreference= StationD: 52044a0 SelectSoftKeys instance=0 reference=0 softkeysetindex=0 validkeymask=7. StationD: 52044a0 DisplayPromptStatus timeoutvalue=0 promptstatus='your current options' lineinstance=0 callreference =0. StationD: 52044a0 ActivateCallPlane lineinstance=0. StationD: 52044a0 SetLamp stimulus=9(line) stimulusinstance=1 lampmode=1(lampoff). StationD: 52044a0 DefineTimeDate timedateinfo=? systemtime= StationD: 52044a0 StopTone. 64 Copyright Printed in USA.

33 IP Telephony Case Study and Troubleshooting Techniques Case study # 1 IP phone to IP phone Intra-cluster call (successful) Case study # 2 IP phone to IP phone Intra-cluster call (failed) Case study # 3 IP phone to MGCP gateway Case study #4 IP phone to H.323 gateway (with GateKeeper) 65 Intra-Cluster Call Flow Trace User starts entering the digits First digit 1 is dialed StationInit: c KeypadButton kpbutton=1. CallManager stops sending the dial tone to the phone 1000 and collects the other digits entered through the keypad (We dialed 1006) StationD: c StopTone. StationD: c SelectSoftKeys instance=1 reference= softkeysetindex=6 validkeymask=-1. Digit analysis: match(fqcn="1000", cn="1000", pss="pa:employee:cer", dd="1") Digit analysis: potentialmatches=potentialmatchesexist StationInit: c KeypadButton kpbutton=0. Digit analysis: match(fqcn="1000", cn="1000", pss="pa:employee:cer", dd="10") Digit analysis: potentialmatches=potentialmatchesexist StationInit: c KeypadButton kpbutton=0. Digit analysis: match(fqcn="1000", cn="1000", pss="pa:employee:cer", dd="100") Digit analysis: potentialmatches=potentialmatchesexist StationInit: c KeypadButton kpbutton=6. Digit analysis: match(fqcn="1000", cn="1000", pss="pa:employee:cer", dd="1006") 66 Copyright Printed in USA.

34 Intra-Cluster Call Flow Trace No match was found: So CallManager sends a reorder tone to the calling party phone Digit analysis: potentialmatches=nopotentialmatchesexist StationD: c StartTone tone=37(reordertone). 67 IP Telephony Case Study and Troubleshooting Techniques Case study # 1 IP phone to IP phone Intra-cluster call (successful) Case study # 2 IP phone to IP phone Intra-cluster call (failed) Case study # 3 IP phone to MGCP gateway Case study #4 IP phone to H.323 gateway (with GateKeeper) 68 Copyright Printed in USA.

35 IP Phone to Voice Gateway (MGCP) Phone A is registered to CallManager Phone B is connected to a carrier s CO Switch A call is placed from Phone A (1000) to Phone B ( ) Phone A will hang-up first CallManager Cluster 1 CallManager MGCP SCCP 1000 Phone A RTP Stream TDM or Analog Stream PSTN Analog Stream Phone B 69 IP Phone to Voice Gateway (MGCP) IP Phone CCM MGCP Gateway Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) 70 Copyright Printed in USA.

36 IP Phone to Voice Gateway (MGCP) Phone 1000 goes to OffHook StationInit: 51ca448 OffHook. CallManager Instructs the phone to change the lamp status & changes the display on the phone StationD: 51ca448 DisplayText text=' 1000 '. (Not Sent in CCM 3.3) StationD: 51ca448 SetLamp stimulus=9(line) stimulusinstance=1 lampmode=2(lampon). StationD: 51ca448 DisplayPromptStatus timeoutvalue=0 promptstatus='enter number' lineinstance=1 callreference= As there are matches found (no digit dialed yet), potential matches exist Digit analysis: match(fqcn="1000", cn="1000", pss="employee:cer", dd="") Digit analysis: potentialmatches=potentialmatchesexist Note: The trace messages above are not sent to the phone. CallManager instructs the phone to play the inside dial tone StationD: 51ca448 StartTone tone=33(insidedialtone). 71 IP Phone to Voice Gateway (MGCP) IP Phone Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Update Softkeys Play Outside Dial Tone CCM MGCP Gateway 72 Copyright Printed in USA.

37 IP Phone to Voice Gateway (MGCP) Keypad button is pressed StationInit: 51ca448 KeypadButton kpbutton=9. CallManager instructs the phone to stop playing tone (dial tone) StationD: 51ca448 StopTone. Update the softkeys StationD: 51ca448 SelectSoftKeys instance=1 reference= softkeysetindex=6 validkeymask=-1. Digit analysis: As there are matches found (one digit dialed), potential matches exist Digit analysis: match(fqcn="1000", cn="1000", pss="employee:cer", dd="9") Digit analysis: potentialmatches=potentialmatchesexist Note: The trace messages above are not sent to the phone CallManager Instructs the phone to start playing outside dial tone StationD: 51ca448 StartTone tone=34(outsidedialtone). 73 IP Phone to Voice Gateway (MGCP) IP Phone Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Update Softkeys Play Outside Dial Tone Station Stop Tone (Outside Dial Tone) More Station Digits Dialled CCM MGCP Gateway 74 Copyright Printed in USA.

38 IP Phone to Voice Gateway (MGCP) Keypad Button is pressed StationInit: 51ca448 KeypadButton kpbutton=5. CallManager Instructs the phone to stop playing outside dial tone StationD: 51ca448 StopTone. As there are matches found (two digits dialed), potential matches exist Digit analysis: match(fqcn="1000", cn="1000", pss="employee:cer", dd="95") Digit analysis: potentialmatches=exclusivelyoffnetpotentialmatchesexist Note: The trace messages above are not sent to the phone Keypad Button is pressed StationInit: 51ca448 KeypadButton kpbutton=5. As there are matches found (three digits dialed), potential matches exist Digit analysis: match(fqcn="1000", cn="1000", pss="employee:cer", dd="955") Digit analysis: potentialmatches=exclusivelyoffnetpotentialmatchesexist Note: The trace messages above are not sent to the phone 75 IP Phone to Voice Gateway (MGCP) Digit analysis is done Digit analysis: match(fqcn="1000", cn="1000", pss="employee:cer", dd=" ") Digit analysis: analysis results <CT::1,100,95, > PretransformCallingPartyNumber=1000 CallingPartyNumber=1000 DialingPartition=Employee */ sign represents the North American Dial Plan DialingRoutePatternRegularExpression=(9)([2-9][02-9]X)(XXXX) */ this is the actual expression matched DialingWhere= PatternType=National PotentialMatches=NoPotentialMatchesExist DialingSdlProcessId=(1,58,7) PretransformDigitString= PretransformTagsList=ACCESS-CODE:OFFICE-CODE:SUBSCRIBER PretransformPositionalMatchList=9:555:1212 CollectedDigits= UnconsumedDigits= TagsList=OFFICE-CODE:SUBSCRIBER PositionalMatchList=555:1212 Voic box= DisplayName= RouteBlockFlag=RouteThisPattern <snip> 76 Copyright Printed in USA.

39 IP Phone to Voice Gateway (MGCP) IP Phone Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Update Softkeys Play Outside Dial Tone Station Stop Tone (Outside Dial Tone) More Station Digits Dialled CCM CRCX (Create Connection) M: inactive MGCP Gateway CRCX Ack w/ip Addr and UDP Port 77 IP Phone to Voice Gateway (MGCP) Call Manager sends connection request to GW MGCPHandler send msg SUCCESSFULLY to: CRCX 280 MGCP 0.1 C: D M: inactive* *Inactive refers to reservation of a DS0 channel GW sends ACK, including the port number MGCPHandler received msg from: I: 23 v=0 o=- D IN IP s=cisco SDP 0 c=in IP t=0 0 m=audio RTP/AVP 0* *Note the port number of GW s receive channel CM recognizes ACK and port number to be used: MGCPHandler recv CRCX Ack with RTP PortNum: Copyright Printed in USA.

40 IP Phone to Voice Gateway (MGCP) IP Phone Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Update Softkeys Play Outside Dial Tone Station Stop Tone (Outside Dial Tone) More Station Digits Dialled CCM CRCX (Create Connection) M: inactive CRCX Ack w/ip Addr and UDP Port PRI Set up Message MGCP Gateway 79 IP Phone to Voice Gateway (MGCP) Call Manager sends PRI setup message to GW Out Message -- PriSetupMsg -- Protocol= PriNi2Protocol Ie - Ni2BearerCapabilityIe IEData= A2 Ie - Q931ChannelIdIe IEData= A Ie - Q931DisplayIe IEData= 28 0E A D F Ie - Q931CallingPartyIe IEData= 6C Ie - Q931CalledPartyIe IEData= A MMan_Id= 0. (iep= 0 dsl= 0 sapi= 0 ces= 0 IpAddr=f33915ac IpPort=2427) IsdnMsgData2= A A E A D F 6C A ASCII conversion: A D F = Rajesh Ramarao = = Copyright Printed in USA.

41 IP Phone to Voice Gateway (MGCP) Easiest way to decode ISDN messages is with enhanced Q.931 translator 81 IP Phone to Voice Gateway (MGCP) Easiest way to decode ISDN messages is with Enhanced Q.931 Translator SETUP, pd = 8, callref = 0x0002 Bearer Capability i = 0x8090A2, ITU-T standard, Speech, Circuit mode, 64k, µ-law Channel ID i = 0xA98397, PRI interface, Exclusive channel 23 Display i = 'Rajesh Ramarao' Calling Party Number i = '1000' - Plan: Unknown, Type: Unknown, Presentation Allowed, User-provided, not screened Called Party Number i = ' - Plan: ISDN, Type: National Entire Message: 0010: A A : 0E A D F 6C 0030: A : Copyright Printed in USA.

42 Q931 Translator (Cont.) 83 IP Phone to Voice Gateway (MGCP) IP Phone Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) CCM MGCP Gateway Station Stop Tone (Dial Tone) Update Softkeys Play Outside Dial Tone Station Stop Tone (Outside Dial Tone) More Station Digits Dialled CRCX (Create Connection) M: inactive Refresh Display Stop Tone Open Receive Channel CRCX Ack w/ip Addr and UDP Port PRI Set up Message PRI Call Proceeding MDCX Message, Open RCV Channel Only 84 Copyright Printed in USA.

43 IP Phone to Voice Gateway (MGCP) GW sends PRI call proceeding message In Message -- PriCallProceedingMsg -- Protocol= PriNi2Protocol Ie - Q931ChannelIdIe -- IEData= A MMan_Id= 0. (iep= 0 dsl= 0 sapi= 0 ces= 0 IpAddr=f33915ac IpPort=2427) IsdnMsgData1= A CCM refreshes phone display information StationD: 51ca448 CallState callstate=12(proceed) lineinstance=1 callreference= StationD: 51ca448 CallInfo callingpartyname='rajesh Ramarao' callingparty=1000 cgpnvoic box=1000 calledpartyname='' calledparty= cdpnvoic box= originalcalledpartyname='' originalcalledparty= originalcdpnvoic box= originalcdpnredirectreason=0 lastredirectingpartyname='' lastredirectingparty= lastredirectingvoic box= lastredirectingreason=0 calltype=2(outbound) lineinstance=1 callreference= StationD::star_StationOutputCallInfo(): callinfo: CI= , CallingPartyName=Rajesh Ramarao, CallingParty=1000, CalledPartyName=, CalledParty= , OriginalCalledPartyName=, OriginalCalledParty= , lastredirectingpartyname=, lastredirectingparty= StationD: 51ca448 DialedNumber dialednumber= lineinstance=1 callreference= IP Phone to Voice Gateway (MGCP) CCM sends stop tone message to phone StationD: 51ca448 StopTone. CCM sends open receive channel to phone StationD: 51ca448 OpenReceiveChannel conferenceid=0 passthrupartyid=513 millisecondpacketsize=20 compressiontype=4(media_payload_g711ulaw64k) qualifierin=?. myip: 46a8110a ( ) CCM sends MDCX message to GW, opening rcv channel only MGCPHandler send msg SUCCESSFULLY to: MDCX 281 S0/DS1-0/23@SDA D8E3 MGCP 0.1 C: D I: 23 X: 17 L: p:20, a:pcmu, s:on M: recvonly R: D/[0-9ABCD*#] Q: process,loop 86 Copyright Printed in USA.

44 IP Phone to Voice Gateway (MGCP) IP Phone Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) CCM MGCP Gateway Station Stop Tone (Dial Tone) Update Softkeys Play Outside Dial Tone Station Stop Tone (Outside Dial Tone) More Station Digits Dialled CRCX (Create Connection) M: inactive Refresh Display Stop Tone Open Receive Channel Start txmission CRCX Ack w/ip Addr and UDP Port PRI Set up Message PRI Call Proceeding MDCX Message, Open RCV Channel Only MDCX ACK Open Receive Channel ACK 87 IP Phone to Voice Gateway (MGCP) GW sends MDCX ack MGCPHandler received msg from: CCM identifies TransID: MGCPHandler received RESP header w/ transid= 281 FOUND a match for MDCX Note: the message above in not sent to GW. We will not show further such messages in the flow CCM tells phone to start transmitting StationD: 51ca448 StartMediaTransmission conferenceid=0 passthrupartyid=513 remoteipaddress=f33915ac( ) remoteportnumber=30656 millisecondpacketsize=20 compresstype=4(media_payload_g711ulaw64k) qualifierout=?. myip: 46a8110a ( ) *Note the port number of GW receive channel Phone ACKs open receive channel StationInit: 51ca448 OpenReceiveChannelAck Status=0, IpAddr=0x46a8110a, Port=27132, PartyID=513 *Note the port number of phone s receive channel 88 Copyright Printed in USA.

45 IP Phone to Voice Gateway (MGCP) IP Phone CCM MGCP Gateway Station Off Hook Station Display Text Station Play Tone (Dial Tone) Station Set Lamp (Steady) Station Stop Tone (Dial Tone) Update Softkeys Play Outside Dial Tone Station Stop Tone (Outside Dial Tone) More Station Digits Dialled CRCX (Create Connection) M: inactive Refresh Display Stop Tone Open Receive Channel Start txmission Open Receive Channel ACK CRCX Ack w/ip Addr and UDP Port PRI Set up Message PRI Call Proceeding MDCX Message, Open RCV Channel Only MDCX ACK MDCX Message, Full Audio MDCX ACK 89 IP Phone to Voice Gateway (MGCP) CCM sends GW MDCX to send/receive MGCPHandler send msg SUCCESSFULLY to: MDCX 282 MGCP 0.1 C: D I: 23 X: 17 L: p:20, a:pcmu, s:on M: sendrecv R: D/[0-9ABCD*#] S: Q: process,loop v=0 o= IN EPN S0/DS1-0/23@SDA D8E3 s=cisco SDP 0 t=0 0 c=in IP m=audio RTP/AVP 96 *Note the port number of phone s receive channel a=rtpmap:96 PCMU GW sends MDCX ack MGCPHandler received msg from: Copyright Printed in USA.

46 IP Phone to Voice Gateway (MGCP) From Previous Flow Diagram IP Phone CCM MGCP Gateway Start Txmission Open Receive Channel ACK MDCX ACK MDCX Message, Full Audio MDCX ACK Alerting We Can Hear In-band Audio (Ringback) Coming From the PSTN Update Call State, Display 91 IP Phone to Voice Gateway (MGCP) GW sends alerting message In Message -- PriAlertingMsg -- Protocol= PriNi2Protocol Ie - Q931ProgressIndIe -- IEData= 1E MMan_Id= 0. (iep= 0 dsl= 0 sapi= 0 ces= 0 IpAddr=f33915ac IpPort=2427) IsdnMsgData1= E *The last nibble (8h, or 1000b) indicates that In-band information, or a appropriate pattern is now available ; The ringback tone will be coming from the PSTN in this case; Your mileage may vary CCM refreshes the IP phone call state, display StationD: 51ca448 CallInfo callingpartyname='rajesh Ramarao' callingparty=1000 cgpnvoic box=1000 calledpartyname='' calledparty= cdpnvoic box= originalcalledpartyname='' originalcalledparty= originalcdpnvoic box= originalcdpnredirectreason=0 lastredirectingpartyname='' lastredirectingparty= lastredirectingvoic box= lastredirectingreason=0 calltype=2(outbound) lineinstance=1 callreference= StationD::star_StationOutputCallInfo(): callinfo: CI= , CallingPartyName=Rajesh Ramarao, CallingParty=1000, CalledPartyName=, CalledParty= , OriginalCalledPartyName=, OriginalCalledParty=, lastredirectingpartyname=, lastredirectingparty= StationD: 51ca448 CallState callstate=3(ringout) lineinstance=1 callreference= StationD: 51ca448 SelectSoftKeys instance=1 reference= softkeysetindex=8 validkeymask=-1. StationD: 51ca448 DisplayPromptStatus timeoutvalue=0 promptstatus='ring Out' lineinstance=1 callreference= Copyright Printed in USA.

47 IP Phone to Voice Gateway (MGCP) From Previous Flow Diagram IP Phone CCM MGCP Gateway Start Txmission Open Receive Channel ACK MDCX ACK MDCX Message, Full Audio MDCX ACK Alerting We Can Hear In-band Audio (Ringback) Coming From the PSTN Update Call State, Display Stop Tone Update Call State, Display PRI Connect Message PRI Connect Msg ACK We Can Hear In-band Audio (Voice) Coming From the PSTN 93 IP Phone to Voice Gateway (MGCP) GW sends PRI connect message In Message -- PriConnectMsg -- Protocol= PriNi2Protocol Ie - Q931ProgressIndIe -- IEData= 1E MMan_Id= 0. (iep= 0 dsl= 0 sapi= 0 ces= 0 IpAddr=f33915ac IpPort=2427) IsdnMsgData1= E *The last nibble (2h, or 0010b) indicates that Destination address is non- ISDN ; Your mileage may vary CCM sends ACK Out Message -- PriConnectAcknowledgeMsg -- Protocol= PriNi2Protocol MMan_Id= 0. (iep= 0 dsl= 0 sapi= 0 ces= 0 IpAddr=f33915ac IpPort=2427) IsdnMsgData2= F CCM tells phone to stop tone StationD: 51ca448 StopTone. 94 Copyright Printed in USA.

48 IP Phone to Voice Gateway (MGCP) CCM Updates phone state, display StationD: 51ca448 CallState callstate=5(connected) lineinstance=1 callreference= StationD: 51ca448 CallInfo callingpartyname='rajesh Ramarao' callingparty=1000 cgpnvoic box=1000 calledpartyname='' calledparty= cdpnvoic box= originalcalledpartyname='' originalcalledparty= originalcdpnvoic box= originalcdpnredirectreason=0 lastredirectingpartyname='' lastredirectingparty= lastredirectingvoic box= lastredirectingreason=0 calltype=2(outbound) lineinstance=1 callreference= StationD::star_StationOutputCallInfo(): callinfo: CI= , CallingPartyName=Rajesh Ramarao, CallingParty=1000, CalledPartyName=, CalledParty= , OriginalCalledPartyName=, OriginalCalledPar ty=, lastredirectingpartyname=, lastredirectingparty= StationD: 51ca448 SelectSoftKeys instance=1 reference= softkeysetindex=1 validkeymask=-1. StationD: 51ca448 DisplayPromptStatus timeoutvalue=0 promptstatus='connected' lineinstance=1 callreference= IP Phone to Voice Gateway (MGCP) From Previous Flow Diagram IP Phone CCM MGCP Gateway Start Txmission Open Receive Channel ACK MDCX ACK MDCX Message, Full Audio MDCX ACK Alerting We Can Hear In-band Audio (Ringback) Coming From the PSTN Update Call State, Display Stop Tone Update Call State, Display PRI Connect Message PRI Connect Msg ACK Notify We Can Hear In-band Audio (Voice) Coming From the PSTN Notify ACK 96 Copyright Printed in USA.

49 IP Phone to Voice Gateway (MGCP) GW sends Notify to CCM MGCPHandler received msg from: NTFY MGCP 0.1 X: 0 O: CCM ACKs the Notify from GW MGCPHandler send msg SUCCESSFULLY to: Notify and notify ack sequence serves as keepalive message; We will disregard from the rest fo the flow 97 IP Phone to Voice Gateway (MGCP) From Previous Flow Diagram IP Phone CCM MGCP Gateway Start Txmission Open Receive Channel ACK MDCX ACK MDCX Message, Full Audio MDCX ACK Alerting We Can Hear In-band Audio (Ringback) Coming From the PSTN Update Call State, Display Stop Tone Update Call State, Display PRI Connect Message PRI Connect Msg ACK Notify Notify ACK End Softkey Event We Can Hear In-band Audio (Voice) Coming From the PSTN Phone State Update (Spkr Off, Display, Etc ) 98 Copyright Printed in USA.

50 IP Phone to Voice Gateway (MGCP) Phone softkey event: end key is pressed StationInit: 51ca448 SoftKeyEvent softkeyevent=9(endcall) lineinstance=1 callreference= CCM updates IP phone state (tone, spkr off, display ) StationD: StationD: StationD: 51ca448 SetSpeakerMode speakermode=2(off). 51ca448 SetSpeakerMode speakermode=2(off). 51ca448 ClearPromptStatus lineinstance=1 callreference= StationD: 51ca448 CallState callstate=2(onhook) lineinstance=1 callreference= StationD: 51ca448 SelectSoftKeys instance=0 reference=0 softkeysetindex=0 validkeymask=7. StationD: 51ca448 DisplayPromptStatus timeoutvalue=0 promptstatus='your current options' lineinstance=0 callreference=0. StationD: 51ca448 ActivateCallPlane lineinstance=0. StationD: 51ca448 SetLamp stimulus=9(line) stimulusinstance=1 lampmode=1(lampoff). StationD: 51ca448 DefineTimeDate timedateinfo=? systemtime= StationD: 51ca448 StopTone. 99 IP Phone to Voice Gateway (MGCP) From Previous Flow Diagram IP Phone CCM MGCP Gateway Start Txmission Open Receive Channel ACK MDCX ACK MDCX Message, Full Audio MDCX ACK Alerting We Can Hear In-band Audio (Ringback) Coming From the PSTN Update Call State, Display Stop Tone Update Call State, Display PRI Connect Message PRI Connect Msg ACK Notify Notify ACK End Softkey Event We Can Hear In-band Audio (Voice) Coming From the PSTN Phone State Update (Spkr Off, Display, Etc ) Close Receive Channel Stop Media Transmission MDCX Message, RCV Channel Only PRI Disconnect Message 100 Copyright Printed in USA.

51 IP Phone to Voice Gateway (MGCP) CCM tells phone to close receive channel StationD: 51ca448 CloseReceiveChannel conferenceid=0 passthrupartyid=513. myip: 46a8110a ( ) CCM tells phone to stop transmitting StationD: 51ca448 StopMediaTransmission conferenceid=0 passthrupartyid=513. myip: 46a8110a ( ) CCM send MDCX receive only message to GW MGCPHandler send msg SUCCESSFULLY to: MDCX 283 MGCP 0.1 C: D I: 23 X: 17 M: recvonly R: D/[0-9ABCD*#] Q: process,loop CCM send PRI Disconnect msg to GW Out Message -- PriDisconnectMsg -- Protocol= PriNi2Protocol Ie - Q931CauseIe IEData= MMan_Id= 0. (iep= 0 dsl= 0 sapi= 0 ces= 0 IpAddr=f33915ac IpPort=2427) IsdnMsgData2= IP Phone to Voice Gateway (MGCP) From Previous Flow Diagram IP Phone CCM MGCP Gateway Start Txmission Open Receive Channel ACK MDCX ACK MDCX Message, Full Audio MDCX ACK Alerting We Can Hear In-band Audio (Ringback) Coming From the PSTN Update Call State, Display Stop Tone Update Call State, Display PRI Connect Message PRI Connect Msg ACK Notify Notify ACK End Softkey Event We Can Hear In-band Audio (Voice) Coming From the PSTN Phone State Update (Spkr Off, Display, Etc ) Close Receive Channel Stop Media Transmission MDCX Message, RCV Channel Only PRI Disconnect Message PRI Release Message Release Complete Phone Handset Put Back on Hook Delete Connection Msg 102 Copyright Printed in USA.

52 IP Phone to Voice Gateway (MGCP) GW sends PRI release message to CCM In Message -- PriReleaseMsg -- Protocol= PriNi2Protocol MMan_Id= 0. (iep= 0 dsl= 0 sapi= 0 ces= 0 IpAddr=f33915ac IpPort=2427) IsdnMsgData1= D CCM sends PRI release message complete to GW Out Message -- PriReleaseCompleteMsg -- Protocol= PriNi2Protocol MMan_Id= 0. (iep= 0 dsl= 0 sapi= 0 ces= 0 IpAddr=f33915ac IpPort=2427) IsdnMsgData2= A CCM sends delete connection message to GW MGCPHandler send msg SUCCESSFULLY to: DLCX 284 S0/DS1-0/23@SDA D8E3 MGCP 0.1 C: D I: 23 X: 17 S: Phone handset put back on hook StationInit: 51ca448 OnHook. CCM refreshes the IP phone call state, display StationD: 51ca448 DefineTimeDate timedateinfo=? systemtime= StationD: 51ca448 StopTone. StationD: 51ca448 SelectSoftKeys instance=0 reference=0 softkeysetindex=0 validkeymask= IP Telephony Case Study and Troubleshooting Techniques Case study # 1 IP phone to IP phone Intra-cluster call (successful) Case study # 2 IP phone to IP phone Intra-cluster call (failed) Case study # 3 IP phone to MGCP gateway Case study #4 IP phone to H.323 gateway (with GateKeeper) 104 Copyright Printed in USA.

53 IP Phone to Voice Gateway (H.323) Phone A is registered to CallManager Phone B is connected to a carrier s CO Switch Call is placed from Phone A ( ) to Phone B ( ) Phone B will hang-up first CallManager Cluster 1 CallManager RAS H.323 SCCP Phone A GK RTP Stream ISDN Q.931 PSTN Analog Stream Phone B 105 IP Phone to H.323 Gateway Gatekeeper Admission Request/Confirm GK CCM GW CO ARQ ( ) ACF ( ) 106 Copyright Printed in USA.

54 Gatekeeper ARQ/ACF CCM Trace CCM sends Admission Request (ARQ) to GK value V2Message ::= admissionrequest : { destinationinfo { e164 : " } CCM receives Admission Confirm (ACF) from GK value V2Message ::= admissionconfirm : { destcallsignaladdress ipaddress : { ip 'AC15338F'H, port 1720 } ACF contains gateway IP address in hex format AC15338F = Gatekeeper ARQ/ACF GK debugs GK receives Admission Request (ARQ) from CCM (debug ras) RecvUDP_IPSockData successfully rcvd message of length 118 from :1603 ARQ (seq# 1706) rcvd Gk sends Admission Confirm (ACF) to CCM (debug ras) IPSOCK_RAS_sendto: msg length 46 from :1719 to : 1603 RASLib::RASSendACF: ACF (seq# 1706) sent to Copyright Printed in USA.

55 IP Phone to H.323 Gateway H.225 and Q.931 Setup/CallProceeding GK CCM GW CO ARQ ACF H.225 Setup H.225 CallProceeding Q.931 Setup Q.931 CallProceeding 109 H.225 Setup/CallProceed CCM trace CCM sends H.225 Setup to GW Out Message -- H225SetupMsg -- Protocol= H225Protocol Ie - Q931DisplayIe IEData= 28 0A C 6C Ie - H225CallingPartyIe IEData= 6C Ie - Q931CalledPartyIe IEData= CCM receives H.225 CallProceeding from GW In Message -- H225CallProceedingMsg -- Protocol= H225Protocol ASCII name and number in Information Elements (IE): C 6C = Bill Gates = = Copyright Printed in USA.

56 Q.931 and H.225 Setup/CallProceed Cisco IOS GW GW receives H.225 Setup from CCM (debug h225 asn1) value H323_UserInformation ::= { h323-uu-pdu { h323-message-body setup : { sourceaddress { h323-id : {"Bill Gates"} } destinationaddress { dialeddigits : " } GW sends Q931 Setup to CO (debug isdn q931) ISDN Se1/0:23 Q931: TX -> SETUP pd = 8 callref = 0x002A Display i = 'Bill Gates Calling Party Number i = 0x0081, ' ' Called Party Number i = 0x80, ' ' 111 Q.931 and H.225 Setup/CallProceed Cisco IOS GW GW receives proceeding from CO (debug isdn q931) ISDN Se1/0:23 Q931: RX <- CALL_PROC pd = 8 callref = 0x802A Channel ID i = 0xA98386 Exclusive, Channel Copyright Printed in USA.

57 IP Phone to H.323 Gateway H.225 and Q.931 Alerting GK CCM GW CO ARQ ACF H.225 Setup Q.931 Setup H.225 CallProceeding Q.931 CallProceeding H.225 Alerting Q.931 Alerting 113 Q.931 and H.225 Alerting GW and CCM GW receives Q.931 Alerting from CO ( debug isdn q931) ISDN Se1/0:23 Q931: RX <- ALERTING pd = 8 callref = 0x802A Progress Ind i = 0x In-band info or appropriate now available GW sends H.225 Alerting to CCM (debug h225 asn1) value H323_UserInformation ::= { h323-uu-pdu { h323-message-body alerting : value H323_UU_NonStdInfo ::= { protoparam qsignonstdinfo : { iei 30 rawmesg '1E028088'H CCM receives H.225 Alerting from GW (ccm trace) In Message -- H225AlertMsg -- Protocol= H225Protocol Ie - Q931ProgressIndIe -- IEData= 1E Copyright Printed in USA.

58 Progress Indicators (PI) Progress Indicators values ISDN Se1/0:23 Q931: RX <- ALERTING pd = 8 callref = 0x802A Progress Ind i = 0x In-band info or appropriate now available 1: not end-to-end ISDN, further call prog info may be available in-band 2: destination address is non-isdn 3: origination address is non-isdn 8: in-band info now available Force PI to make Call Progress tones work dial-peer voice 1 pots progress_ind [setup alert] enable [ ] 115 IP Phone to H.323 Gateway H.245 Media Negotiations GK CCM GW CO ARQ ACF H.225 Setup Q.931 Setup H.225 CallProceeding Q.931 CallProceeding H.225 Alerting Q.931 Alerting H.245 terminalcapabilityset H.245 masterslavedetermination 116 Copyright Printed in USA.

59 H.245 Codec Negotiation GW and CCM GW advertises preferred codecs (debug h245 asn1) value MultimediaSystemControlMessage ::= request : terminalcapabilityset : { capabilitytable { { capabilitytableentrynumber 4 capability receiveaudiocapability : g729annexa : 2 }, { capabilitytableentrynumber 3 capability receiveaudiocapability : g729 : 2 }, { capabilitytableentrynumber 1 capability receiveaudiocapability : g711ulaw64k : 20 CCM advertises preferred codecs in terminalcapabilityset H245ASN MultimediaSystemControlMessage ::= request : terminalcapabilityset { capabilitytable { { capabilitytableentrynumber 1, capability receiveaudiocapability : g711ulaw64k : H.245 Codec Negotiation GW and CCM GW announces chosen codec (debug h245 asn1) value MultimediaSystemControlMessage ::= response : terminalcapabilitysetack : { sequencenumber 1 } CCM announces chosen codec in terminalcapabilitysetack H245ASN - TtPid=(1,100,108,42) -Outgoing -value MultimediaSystemControlMessage ::= response : terminalcapabilitysetack : { sequencenumber 1 } Codec controlled via Region on CCM & voice-class on GW : voice class codec 10 codec preference 1 g711ulaw codec preference 2 g729r8 dial-peer voice voip incoming called-number. voice -class codec Copyright Printed in USA.

60 IP Phone to Voice Gateway (H.323) H.323 Q.931 PSTN SCCP RTP Phone B IP Phone to H.323 Gateway H.245 and SSCP Media Cut-Through IP Phone CCM GW CO H.225 Setup H.225 CallProceeding Q.931 Setup Q.931 CallProceeding H.225 Alerting Q.931 Alerting H.245 terminalcapabilityset H.245 masterslavedetermination H.245 openlogicalchannel SCCP StartMediaTrans SCCP OpenReceiveChan H.245 openlogicalchannelack H.245 openlogicalchannel SCCP OpenReceiveChanAck H.245 openlogicalchannelack We Can Hear In-band Call Progress Tones Coming From the PSTN 120 Copyright Printed in USA.

61 H.245 Media Cut Through GW to Phone CCM tells GW to get ready to receive RTP from IP Phone H245ASN - Outgoing MultimediaSystemControlMessage ::= request : openlogicalchannel : GW responds to CM with UDP port number it is listening on value MultimediaSystemControlMessage ::= response : openlogicalchannelack : { mediachannel unicastaddress : ipaddress : { network 'AC15338F'H tsapidentifier CCM directs phone to start transmitting RTP StationD: StartMediaTransmission remoteipaddress=8f3315ac( ) remoteportnumber=17256 millisecondpacketsize=20 compresstype=4(media_payload_g711ulaw64k) IP address format: AC15338F = H.245 Media Cut Through Phone to GW CCM hears from GW that it should get ready to receive RTP from GW H245ASN - Incoming MultimediaSystemControlMessage ::= request : openlogicalchannel : CCM passes the word onto the phone: Get ready to receive RTP StationD: OpenReceiveChannel millisecondpacketsize=20 compressiontype=4(media_payload_g711ulaw64k) Phone responds to CM with the UDP port number it is listening on StationInit: OpenReceiveChannelAck IpAddr=0xdb915e0a, Port=24614 CCM passes the phone IP address and port number to GW H245ASN -Outgoing -value MultimediaSystemControlMessage ::= response : openlogicalchannelack : { mediachannel unicastaddress : ipaddress : { network '0A5E91DB'H, tsapidentifier Note IP address format: 0A5E91DB & db915e0a = Copyright Printed in USA.

62 IP Phone to H.323 Gateway Connect PSTN Phone Answers IP Phone CCM GW CO H.225 Setup H.225 CallProceeding Q.931 Setup Q.931 CallProceeding H.225 Alerting Q.931 Alerting H.245 terminalcapabilityset H.245 masterslavedetermination H.245 openlogicalchannel SCCP StartMediaTrans SCCP OpenReceiveChan H.245 openlogicalchannelack H.245 openlogicalchannel SCCP OpenReceiveChanAck H.245 openlogicalchannelack We Can Hear In-band Call Progress Tones Coming From the PSTN H.225 Connect Q.931 Connect Q.931 Connect Ack 123 H.245 and Q.931 Connect CO tells GW that called party has answered the call ISDN Se1/0:23 Q931: RX <- CONNECT pd = 8 callref = 0x802A Display i = 'John Chambers ISDN Se1/0:23 Q931: TX -> CONNECT_ACK pd = 8 callref = 0x002A GW tells CCM that the call has been answered value H323_UserInformation ::= { h323-uu-pdu { h323-message-body connect : CCM hears from the GW that phone B has answered In Message -- H225ConnectMsg -- Protocol= H225Protocol 124 Copyright Printed in USA.

63 IP Phone to H.323 Gateway Connect PSTN Phone Disconnects GK CCM GW CO ARQ ( ) ACF ( ) H.225 Setup H.225 CallProceeding Q.931 Setup Q.931 CallProceeding H.225 Alerting Q.931 Alerting H.245 terminalcapabilityset H.245 masterslavedetermination H.245 openlogicalchannel H.245 openlogicalchannelack H.245 openlogicalchannel H.245 openlogicalchannelack We Can Hear In-band Call Progress Tones Coming From the PSTN H.225 Connect H.225 ReleaseComplete Q.931 Connect Q.931 Connect Ack Q.931 Disconnect Q.931 Release DRQ DCF H.245 closelogicalchannel H.245 closelogicalchannelack 125 H.245 and Q.931 Disconnect CO tells GW that phone B has hung up ISDN Se1/0:23 Q931: RX <- DISCONNECT pd = 8 callref = 0x802A Cause i = 0x Normal call clearing ISDN Se1/0:23 Q931: TX -> RELEASE pd = 8 callref = 0x002A CCM hears from the GW that phone B has hung up In Message -- H225ReleaseCompleteMsg -- Protocol= H225Protocol Ie - Q931CauseIe -- IEData= Disconnect cause codes assist in troubleshooting: 90h = b b = 16 gateway#show call history voice include DisconnectText DisconnectText=normal call clearing (16) DisconnectText=unassigned number (1) DisconnectText=user busy (17) DisconnectText=no circuit (34) 126 Copyright Printed in USA.

64 Summary Remember what is supposed to happen when there is no problem; simulate, re-create, stare and compare, etc Traces are your friend!!! Assume that there is a perfectly logical explanation for the behavior you are investigating: 99% of the time, you ll be right For the remaining 1%, TAC will want to see the traces; be prepared to share the traces if need be Read the technical tips on Cisco TAC web site at Other Resources 128 Copyright Printed in USA.

65 More Information For more details on reading CCM traces, see here: Troubleshooting Cisco IP Telephony ISBN CiscoWorks IP Telephony Environment Monitor (ITEM) Additional IP Telephony Troubleshooting and Monitoring 130 Copyright Printed in USA.

66 IP Telephony Environment Monitor Provides real-time assessment of the operational health of IP telephony environments Provides threshold analysis, alerting and notification about key operational exceptions; ensuring maximum availability of their IP telephony installation Has the expertise built in user does not have to configure or develop analysis rules to effectively troubleshoot and monitor their IP telephony space 131 What ITEM Does ITEM continuously monitors the health of IP telephony installations (including CCMs, switches, gateways, and IP phones) and underlying IP fabric IP Telephony CCM IP fabric Customer is alerted when a problem is detected or a future problem is suspected Alerting function can send information to paging and servers as well as centralized network management servers 132 Copyright Printed in USA.

67 ITEM In Your Network Fault and health monitoring of IP fabric Cisco IP telephony implementation fault and health monitoring/alerting PTT/PSTN Synthetic Traffic Traps Polls & Pings CiscoWorks ITEM E and Pager Alerts and Events CIC Trap Forwarding CCM CiscoWorks Desktop IP Phone Help Desk Utility Web-Based Access 133 Who Needs It? Primary focus: Enterprise customer implementing at least 200 Cisco IP telephones Typical installations will have Cisco IP infrastructure with In-line power switches CCMs Cisco IP telephones AVVID-enabled IP telephony applications 134 Copyright Printed in USA.

68 Additional Information For more information on CiscoWorks ITEM go to: Or the CiscoWorks demonstration booth! To order CiscoWorks ITEM 1.3 reference part number: CWITEM-1.3-WIN-K9 For information on all CiscoWorks management products: Recommended Reading Troubleshooting Cisco IP Telephony ISBN: Available on-site at the Cisco Company Store 136 Copyright Printed in USA.