Use the show cops servers command to see that the COPS connection to the PS is established (the client type should be 32778).
If the COPS connection is not there, you can check to see whether the PS has opened the TCP connection (to port 3918 on the CMTS) using the show tcp brief command.
The show packetcable global command tells you whether PCMM is enabled and the value of timer T1.
The show packetcable gate command shows you information on PCMM gates, just as it did with PC 1.x gates. The multimedia keyword can be used to just show PCMM gates if you have both types on the CMTS. The following is some sample output of PCMM gates:
C0103-7246VXR#show packetcable gate multimedia summary GateID i/f SubscriberID GC-Addr State Type SFID(us) SFID(ds) 37938 Ca5/0 24.34.240.247 172.18.98.62 COMMIT MM 222 54322 Ca5/0 24.34.240.247 172.18.98.62 COMMIT MM 221 Total number of Multimedia gates = 2 Total Gates committed(since bootup or clear counter) = 92
C0103-7246VXR#show packetcable gate 54322 <- Detailed information for Upstream PCMM gate
GateID : 54322 Subscriber ID : 24.34.240.247 COPS server handle : 0x644754F8 State : COMMIT Upstream classifier : protocol : 0 priority : 64 src addr/port : 24.34.240.247/0 dest addr/port : 0.0.0.0/0 dscp-tos/mask : 0x0 0x0 gate spec : flags 0x1 dscp-tos/mask : 0x0 0x0 timer t1(s) : 200 timer t2(s) : 0 timer t3(s) : 0 timer t4(s) : 0 session class : 0x0 Traffic Profile : Best Effort.Authorized : <- Below is the Authorized Resource Envelope
Traffic Priority 0x0 Req Transmission Policy 0x0 Max Sustain Rate 2300000 Max Burst 3044 Min Rate 0 Min pkt size 64Reserved : <- Below is the Reserved Resource Envelope
Traffic Priority 0x0 Req Transmission Policy 0x0 Max Sustain Rate 2300000 Max Burst 3044 Min Rate 0 Min pkt size 64Committed : <- Below is the Committed Resource Envelope
Traffic Priority 0x0 Req Transmission Policy 0x0 Max Sustain Rate 2300000 Max Burst 3044 Min Rate 0 Min pkt size 64C0103-7246VXR#show packetcable gate 37938 <- Detailed information for Downstream PCMM gate
GateID : 37938 Subscriber ID : 24.34.240.247 COPS server handle : 0x644754F8 State : COMMIT Downstream classifier : protocol : 0 priority : 64 src addr/port : 0.0.0.0/0 dest addr/port : 24.34.240.247/0 dscp-tos/mask : 0x0 0x0 gate spec : flags 0x0 dscp-tos/mask : 0x0 0x0 timer t1(s) : 200 timer t2(s) : 0 timer t3(s) : 0 timer t4(s) : 0 session class : 0x0 Traffic Profile : Downstream.Authorized : <- Below is the Authorized Resource Envelope
Traffic priority 0 Max Sustain Rate 17500000 Max Burst 3044 Min Rate 0 Min pkt size 64 DS Latency 0Reserved : <- Below is the Reserved Resource Envelope
Traffic priority 0 Max Sustain Rate 17500000 Max Burst 3044 Min Rate 0 Min pkt size 64 DS Latency 0Committed : <- Below is the Committed Resource Envelope
Traffic priority 0 Max Sustain Rate 17500000 Max Burst 3044 Min Rate 0 Min pkt size 64 DS Latency 0The show packetcable gate counter multimedia command tells you the number of PCMM gates committed since the CMTS was last reset or the counter was cleared (this can be done with the command clear packetcable gate counter commit multimedia).
DOCSIS Service Flows, Classifiers, and SIDs created as a result of PCMM can be seen using the same commands described in the last chapter.
Use the show controller cable x/y downstream command to view statistics on DSX messages. For PCMM, you see hits on the Request and Acknowledgement counters for DSA and DSC messages because these always originate from the CMTS for PCMM client type 1 devices.
The debugging of DOCSIS service flow creation as a result of PCMM can be seen with the same commands that are used for PC 1.x, as described in Chapter 13.
Likewise, the debugging of COPS gate messaging for PCMM can be seen with the same commands that are used for PC 1.x DQoS. The following is an example of the debug packetcable gate control command output used with the debug packetcable subscriber sub IP verbose command:
Aug 10 20:22:06.984: Pktcbl(mm): Received GATE SET message, tid=0x6DCE Aug 10 20:22:06.984: --- Pktcbl(mm): Received GCP message ------ Aug 10 20:22:06.984: TRANSACTION ID : Object.[snum/stype/len 1/1/8] Aug 10 20:22:06.984: transaction id : 0x6DCE Aug 10 20:22:06.984: gcp cmd : 4 (GATE SET) Aug 10 20:22:06.984: AM ID : Object.[snum/stype/len 2/1/8] Aug 10 20:22:06.984: AM ID : 1 Aug 10 20:22:06.984: SUBSCRIBER ID (IPV4) : Object.[snum/stype/len 3/1/8] Aug 10 20:22:06.984: Addr : 24.34.240.247 Aug 10 20:22:06.984: GATE SPEC : Object.[snum/stype/len 5/1/16] Aug 10 20:22:06.984: flag : 0x1 Aug 10 20:22:06.984: dscp : 0x0 Aug 10 20:22:06.984: dscp tos mask : 0x0 Aug 10 20:22:06.984: Timers t1 : 0, t2 : 0 Aug 10 20:22:06.984: t3 : 0, t4 : 0 Aug 10 20:22:06.984: session class : 0x0 Aug 10 20:22:06.984: TRAFFIC PROFI C0103-7246VXR#LE : Object.[snum/stype/len 7/3/80] Aug 10 20:22:06.984: envelope : 0x7 Aug 10 20:22:06.984: service number : 0x0 Aug 10 20:22:06.984: Authorized : Aug 10 20:22:06.984: Traffic Priority : 0 Aug 10 20:22:06.984: Request Xmit Policy: 0x0 Aug 10 20:22:06.984: Max Sustained Rate : 2300000 Aug 10 20:22:06.984: Max Burst : 3044 Aug 10 20:22:06.984: Min Reserved Rate : 0 Aug 10 20:22:06.984: Min Pkt Size : 64 Aug 10 20:22:06.984: Reserved : Aug 10 20:22:06.984: Traffic Priority : 0 Aug 10 20:22:06.984: Request Xmit Policy: 0x0 Aug 10 20:22:06.984: Max Sustained Rate : 2300000 Aug 10 20:22:06.984: Max Burst : 3044 Aug 10 20:22:06.984: Min Reserved Rate : 0 Aug 10 20:22:06.984: Min Pkt Size : 64 Aug 10 20:22:06.984: Committed : Aug 10 20:22:06.984: Traffic Priority : 0 Aug 10 20:22:06.984: Request Xmit Policy: 0x0 Aug 10 20:22:06.984: Max Sustained Rate : 2300000 Aug 10 20:22:06.984: Max Burst : 3044 Aug 10 20:22:06.984: Min Reserved Rate : 0 Aug 10 20:22:06.984: Min Pkt Size : 64 Aug 10 20:22:06.984: CLASSIFIER : Object.[snum/stype/len 6/1/24] Aug 10 20:22:06.984: protocol : 0x0 Aug 10 20:22:06.984: dscp : 0x0 Aug 10 20:22:06.984: dscp tos mask : 0x0 Aug 10 20:22:06.984: src/port : 24.34.240.247 0 Aug 10 20:22:06.984: dest/port : 0.0.0.0 0 Aug 10 20:22:06.984: priority : 64 Aug 10 20:22:06.984: OPAQUE : Object.[snum/stype/len 11/1/12] Aug 10 20:22:06.984: data : [33 36 34 31 39 31 38 00 ] Aug 10 20:22:06.984: -------------------------------------- Aug 10 20:22:06.984: Pktcbl(mm): Change profile 0 qos 0 Aug 10 20:22:06.996: Pktcbl(mm): Building GCP message, added obj TRANSACTION ID ; len:8 padding:0 Aug 10 20:22:06.996: Pktcbl(mm): Building GCP message, added obj AM ID ; len:8 padding:0 Aug 10 20:22:06.996: Pktcbl(mm): Building GCP message, added obj SUBSCRIBER ID (IPV4); len:8 padding:0 Aug 10 20:22:06.996: Pktcbl(mm): Building GCP message, added obj GATE ID ; len:8 padding:0 Aug 10 20:22:06.996: Pktcbl(mm): Building GCP message, added obj OPAQUE ; len:12 padding:0 Aug 10 20:22:06.996: Pktcbl(mm): Built GCP message, GATE SET ACK , length: 44, copsLen 72 Aug 10 20:22:06.996: --- Pktcbl: Sending GCP message ------ Aug 10 20:22:06.996: TRANSACTION ID : Object.[snum/stype/len 1/1/8] Aug 10 20:22:06.996: transaction id : 0x6DCE Aug 10 20:22:06.996: gcp cmd : 5 (GATE SET ACK) Aug 10 20:22:06.996: AM ID : Object.[snum/stype/len 2/1/8] Aug 10 20:22:06.996: AM ID : 1 Aug 10 20:22:06.996: SUBSCRIBER ID (IPV4) : Object.[snum/stype/len 3/1/8] Aug 10 20:22:06.996: Addr : 24.34.240.247 Aug 10 20:22:06.996: GATE ID : Object.[snum/stype/len 4/1/8] Aug 10 20:22:06.996: GateID : 37942 (0x9436) Aug 10 20:22:06.996: OPAQUE : Object.[snum/stype/len 11/1/12] Aug 10 20:22:06.996: data : [33 36 34 31 39 31 38 00 ] Aug 10 20:22:06.996: -------------------------------------- Aug 10 20:22:07.016: Pktcbl(mm): Received GATE SET message, tid=0x6DCF Aug 10 20:22:07.016: --- Pktcbl(mm): Received GCP message ------ Aug 10 20:22:07.016: TRANSACTION ID : Object.[snum/stype/len 1/1/8] Aug 10 20:22:07.016: transaction id : 0x6DCF Aug 10 20:22:07.016: gcp cmd : 4 (GATE SET) Aug 10 20:22:07.016: AM ID : Object.[snum/stype/len 2/1/8] Aug 10 20:22:07.016: AM ID : 1 Aug 10 20:22:07.016: SUBSCRIBER ID (IPV4) : Object.[snum/stype/len 3/1/8] Aug 10 20:22:07.016: Addr : 24.34.240.247 Aug 10 20:22:07.016: GATE SPEC : Object.[snum/stype/len 5/1/16] Aug 10 20:22:07.016: flag : 0x0 Aug 10 20:22:07.016: dscp : 0x0 Aug 10 20:22:07.016: dscp tos mask : 0x0 Aug 10 20:22:07.016: Timers t1 : 0, t2 : 0 Aug 10 20:22:07.016: t3 : 0, t4 : 0 Aug 10 20:22:07.016: session class : 0x0 Aug 10 20:22:07.016: TRAFFIC PROFILE : Object.[snum/stype/len 7/8/80] Aug 10 20:22:07.016: envelope : 0x7 Aug 10 20:22:07.016: service number : 0x0 Aug 10 20:22:07.016: Authorized : Aug 10 20:22:07.016: Traffic Priority : 0 Aug 10 20:22:07.016: Max Sustained Rate : 17500000 Aug 10 20:22:07.016: Max Burst : 3044 Aug 10 20:22:07.016: Min Reserved Rate : 0 Aug 10 20:22:07.016: Min Pkt Size : 64 Aug 10 20:22:07.016: Max Latency : 0 Aug 10 20:22:07.016: Reserved : Aug 10 20:22:07.016: Traffic Priority : 0 Aug 10 20:22:07.016: Max Sustained Rate : 17500000 Aug 10 20:22:07.016: Max Burst : 3044 Aug 10 20:22:07.016: Min Reserved Rate : 0 Aug 10 20:22:07.016: Min Pkt Size : 64 Aug 10 20:22:07.016: Max Latency : 0 Aug 10 20:22:07.016: Committed : Aug 10 20:22:07.016: Traffic Priority : 0 Aug 10 20:22:07.016: Max Sustained Rate : 17500000 Aug 10 20:22:07.016: Max Burst : 3044 Aug 10 20:22:07.016: Min Reserved Rate : 0 Aug 10 20:22:07.016: Min Pkt Size : 64 Aug 10 20:22:07.016: Max Latency : 0 Aug 10 20:22:07.016: CLASSIFIER : Object.[snum/stype/len 6/1/24] Aug 10 20:22:07.016: protocol : 0x0 Aug 10 20:22:07.016: dscp : 0x0 Aug 10 20:22:07.016: dscp tos mask : 0x0 Aug 10 20:22:07.016: src/port : 0.0.0.0 0 Aug 10 20:22:07.016: dest/port : 24.34.240.247 0 Aug 10 20:22:07.016: priority : 64 Aug 10 20:22:07.016: OPAQUE : Object.[snum/stype/len 11/1/12] Aug 10 20:22:07.016: data : [33 36 34 31 39 31 38 00 ] Aug 10 20:22:07.016: -------------------------------------- Aug 10 20:22:07.016: Pktcbl(mm): Change profile 0 qos 0 Aug 10 20:22:07.040: Pktcbl(mm): Building GCP message, added obj TRANSACTION ID ; len:8 padding:0 Aug 10 20:22:07.040: Pktcbl(mm): Building GCP message, added obj AM ID ; len:8 padding:0 Aug 10 20:22:07.040: Pktcbl(mm): Building GCP message, added obj SUBSCRIBER ID (IPV4); len:8 padding:0 Aug 10 20:22:07.040: Pktcbl(mm): Building GCP message, added obj GATE ID ; len:8 padding:0 Aug 10 20:22:07.040: Pktcbl(mm): Building GCP message, added obj OPAQUE ; len:12 padding:0 Aug 10 20:22:07.040: Pktcbl(mm): Built GCP message, GATE SET ACK , length: 44, copsLen 72 Aug 10 20:22:07.040: --- Pktcbl: Sending GCP message ------ Aug 10 20:22:07.040: TRANSACTION ID : Object.[snum/stype/len 1/1/8] Aug 10 20:22:07.044: transaction id : 0x6DCF Aug 10 20:22:07.044: gcp cmd : 5 (GATE SET ACK) Aug 10 20:22:07.044: AM ID : Object.[snum/stype/len 2/1/8] Aug 10 20:22:07.044: AM ID : 1 Aug 10 20:22:07.044: SUBSCRIBER ID (IPV4) : Object.[snum/stype/len 3/1/8] Aug 10 20:22:07.044: Addr : 24.34.240.247 Aug 10 20:22:07.044: GATE ID : Object.[snum/stype/len 4/1/8] Aug 10 20:22:07.044: GateID : 54326 (0xD436) Aug 10 20:22:07.044: OPAQUE : Object.[snum/stype/len 11/1/12] Aug 10 20:22:07.044: data : [33 36 34 31 39 31 38 00 ] Aug 10 20:22:07.044: --------------------------------------
Finally, many of the test commands covered in Chapter 13 can also be used to troubleshoot the COPS connectivity between the CMTS and PS.
Chapter Summary
The PacketCable Multimedia (PCMM) specifications provide a generalized framework for enabling DOCSIS QoS services for a wide range of multimedia applications. PCMM is unaware of the application specifics; hence, it does not specify application details such as signaling and provisioning. The possible range of PCMM applications includes real-time applications such as videoconferencing, interactive gaming, streaming media, and telephony, as well as non real-time applications such as web-based bandwidth on demand and Speed Preview.
There are seven components in the PCMM architecture: clients, Application Server (AS), Application Manager (AM), Policy Server (PS), CMTS, CM, and RKS. Three types of multimedia clients exist:
Type 1 is referred to as "QoS-unaware" because it knows nothing about the PacketCable network it is using.
Type 2 is referred to as "Push model" because it is QoS-aware but relies on other components such as the AM and PS to push QoS policies to the CMTS.
Type 3 is referred to as "Pull model" because it is QoS-aware and able to trigger the CMTS to pull QoS policies from the PS.
Currently, only type 1 clients are fully defined in PCMM. The AS is an intermediary device that initiates multimedia sessions on behalf of clients. The Application Manager figures out the resources needed by a client and conveys this information to a Policy Server. The Policy Server applies rules to requests from the AM, such as checking CMTS usage and subscriber QoS restrictions. The CMTS, cable modem, and RKS event messaging server perform similar functions in PCMM that they do in PacketCable 1.x. However, significant differences in how these functions are performed do exist. For example, in PCMM dynamic DOCSIS service flow creation is initiated from the CMTS, unlike in PacketCable 1.x, where they are initiated from the embedded MTA.
COPS is used in two places in PCMM--between the AM and PS and between the PS and CMTS. Consequently, a PCMM network is split into service control domains (SCDs) and resource control domains (RCDs). An SCD is a logical grouping of elements that provide an application, and an RCD is the logical grouping of elements providing connecting to QoS resources.
Like PacketCable telephony, the DOCSIS network must be at least DOCSIS 1.1 capable in PCMM. However, the use of DOCSIS in PCMM varies from its previous use. In addition to the unsolicited grant services (UGS and UGS-AD), the polling services are also permitted (RTPS and nRTPS). The Real-Time Polling Service is used for jitter-sensitive applications that transmit variable-sized packets. The Non Real-Time Polling Service is used for applications that are sensitive to packet loss and require regular transmission opportunities but can tolerate packet jitter. Also through the manipulation of certain DOCSIS service flow parameters, the Best Effort scheduling type can also be used in PCMM to provide QoS.
The COPS messaging and parameters used in PCMM are significantly different than those in PacketCable telephony. The COPS protocol is still used for resource allocation and authorization, but in PCMM it is also used for resource reservation and commitment. Among the objects defined in COPS for PCMM are gate specifications, classifiers, and traffic profiles. PCMM gate specifications contain timer values as well as parameters such as gate priority and DSCP overwrite settings, and classifiers determine the type of packets permitted to use a PCMM gate. A traffic profile defines the QoS resources required for the application and can be defined by RSVP flow specifications, DOCSIS TLV parameters, or DOCSIS service class names. Traffic profiles can contain authorized resource envelopes, reserved resource envelopes, and committed resource envelopes. The presence of reserved and committed resource envelopes triggers DOCSIS messages to the cable modem connected to the PCMM subscriber. Also objects exist that can be used to track gate bandwidth use and the time in which PCMM gates are active. The use of event messaging for real-time billing and packet encryption for added security also exist in PCMM, just as they did in telephony.
PCMM configuration and troubleshooting commands on a Cisco CMTS are similar to the corresponding commands used for PacketCable telephony. Show commands exist, which output the current status and details of PCMM gates and their DOCSIS service flows. Debug commands exist, which output the COPS and DOCSIS messaging used to create QoS for PCMM sessions.
Chapter Review
True or False: The Application Manager doesn't need to know the CMTS to which its clients are physically connected.
Answer: True. It relies on the Policy Server to figure this out.
True or False: PCMM defines the protocol used between the AM and PS devices.
Answer: True. The COPS protocol is used.
True or False: PCMM defines the protocol used between the AM or AS and the client devices.
Answer: False. This is out of the scope of PCMM.
True or False: If a PCMM gate is set up using a DOCSIS service class name defined on the CMTS, certain QoS parameters can also be overwritten using DOCSIS TLV parameters.
Answer: False
True or False: The way in which PCMM is configured, verified, and debugged on a Cisco CMTS is nearly identical to the way these things are done for PacketCable telephony.
Answer: True
True or False: A PCMM gate identifier refers to the combination of an upstream gate and a downstream gate.
Answer: False. In PCMM, gates are always unidirectional.
True or False: The types of event messages used in PCMM are different than those used in PC telephony.
Answer: True. Messages specific to the telephony application have been removed and messages sent from the PS have been added.
True or False: The CMTS initiates the deletion of a gate that exceeds its configured volume usage limit or exceeds its time usage limit.
Answer: False. The CMTS is not responsible for enforcing these limits.
True or False: If the CMTS receives a PCMM gate specification with a timer T1 value of 0, this means the resources remain authorized until torn down by the PS.
Answer: False. This means the CMTS provisioned value is used.
What type of multimedia client uses RSVP to set up its QoS?
Answer: Type 3
For each of the following possible PCMM applications, identify the DOCSIS scheduling type (UGS, UGS-AD, RTPS, nRTPS, or BE) that makes the most sense:
Video telephony
On-demand minimal bandwidth guaranteed service
Standalone telephony MTA implementing VAD
Interactive gaming
Answer: a) RTPS, b) BE, c) UGS-AD, d) RTPS
When is a Policy Server a COPS PDP and when is it a COPS PEP?
Answer: The PS is a Policy Decision Point for the resource control domain in its communication with the CMTS and a Policy Enforcement Point for the service control domain in its communication with the AM.
What is the purpose of the Gate Report State message?
Answer: It is sent by the CMTS to alert the PS of a change in the resource status of a gate because of events like client messaging and timer expiry.
What is the TCP port used for PCMM, and why is it different than the one used for PC telephony?
Answer: 3918. So both applications can simultaneously exist without interfering with each other.
What could a Deep Packet Inspection (DPI) device be used for in a PCMM network?
Answer: To initiate PCMM session requests based on inspected packets (such as voice/video RTP streams)
Under what situation would an incremental synchronization request be sent by a PDP?
Answer: To recover gate information after the COPS connection is lost
What is a reason for using extended classifiers over standard classifiers?
Answer: So individual classifiers can be added, activated, or deleted without having to resend the entire list of classifiers, or they could be used to specify a range of IP addresses and port numbers.
Why can't traffic profiles using RSVP flow specs be used to trigger the creation of UGS-AD and nRTPS service flows?
Answer: Because of limitations in the ability to map flow spec parameters into DOCSIS parameters
What Cisco IOS command can be used to see the active list of PCMM gates?
Answer: show packetcable gate multimedia summary
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