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This chapter describes the transcoding support available in Cisco Unified Communications Manager Express (Cisco Unified CME).
 Note |
|
Cisco Unified CME 3.2 or a later version.
Cisco Unified CME 11.6 or later versions for LTI-based transcoding, supported on Cisco 4000 Series Integrated Services Router (ISR).
Before Cisco CME 3.2, only G.729 is supported for two-party voice calls.
In Cisco CME 3.2 to Cisco Unified CME 4.0, transcoding between G.711 and G.729 does not support the following:
Meet-me conferencing
Multiple-party ad-hoc conferencing
Transcoding security
For Cisco Unified CME Release 11.6, hardware conferencing is not supported with LTI-based transcoding on Cisco 4000 Series Integrated Services Router (ISR).
In Unified CME 11.6, SCCP based transcoding is not supported.
Transcoding compresses and decompresses voice streams to match endpoint-device capabilities. Transcoding is required when an incoming voice stream is digitized and compressed (by means of a codec) to save bandwidth, and the local device does not support that type of compression.
Cisco Unified CME 3.2 and later versions support transcoding between G.711 and G.729 codecs for the following features:
Ad hoc conferencing—One or more remote conferencing parties uses G.729.
Call transfer and forward—One leg of a Voice over IP (VoIP)-to-VoIP hairpin call uses G.711 and the other leg uses G.729. A hairpin call is an incoming call that is transferred or forwarded over the same interface from which it arrived.
Cisco Unity Express or Cisco Unity Express Virtual—An H.323 or SIP call using G.729 is forwarded to Cisco Unity Express or Cisco Unity Express Virtual. Cisco Unity Express or Cisco Unity Express Virtual supports only G.711, so G.729 must be transcoded.
From Cisco Unified CME Release 11.6 onwards, SIP calls coming to Cisco Unity Express or Cisco Unity Express Virtual is supported on Cisco 4000 Series ISR routers using the LTI transcoding infrastructure. For more information on configuring LTI transcoding on Cisco Unified CME, see Configure LTI-based Transcoding.
Music on hold (MOH)—The phone receiving MOH is part of a system that uses G.729, G.722, or internet Low Bitrate Codec (iLBC). When the G.711 MOH is transcoded into G.729, it results in a poorer quality sound due to the lower compression of G.729. From Cisco Unified CME Release 11.7 onwards, Music on Hold is supported on Cisco 4000 Series ISR routers using the LTI transcoding infrastructure. For more information on configuring LTI transcoding on Cisco Unified CME, see Configure LTI-based Transcoding.
Each of the preceding call situations is illustrated in Three-Way Conferencing, Call Transfer and Forward, Cisco Unity Express, and MOH Between G.711 and G.729.
Transcoding is facilitated through DSPs, which are located in network modules. All network modules have single in-line memory module (SIMM) sockets or packet voice/data modules (PVDM) slots that each hold a Packet Voice DSP Module (PVDM). Each PVDM holds DSPs. A router can have multiple network modules.
Cisco Unified CME routers and external voice routers on the same LAN must be configured with digital signal processors (DSPs) that support transcoding. DSPs reside either directly on a voice network module, such as the NM-HD-2VE, on PVDM2s that are installed in a voice network module, such as the NM-HDV2, or on PVDM2s that are installed directly onto the motherboard, such as on the Cisco 2800 and 3800 series voice gateway routers.
DSPs on the NM-HDV, NM-HDV2, NM-HD-1V, NM-HD-2V, and NM-HD-2VE can be configured for transcoding.
PVDM2-xx on the Cisco 2800 series and the Cisco 3800 series motherboards can also be configured for transcoding.
Transcoding of G.729 calls to G.711 allows G.729 calls to participate in existing G.711 software-based, three-party conferencing, thus eliminating the need to divide DSPs between transcoding and conferencing.
NM-HDV Supports up to Five PVDMs shows an NM-HDV with five SIMM sockets or PVDM slots that each hold a 12-Channel PVDM (PVDM-12). Each PVDM-12 holds three TI 549 DSPs. Each DSP supports four channels.
Use DSP resources to provide voice termination of the digital voice trunk group or resources for a DSP farm. DSP resources available for transcoding and not used for voice termination are referred to as a DSP farm. DSP Farm shows a DSP farm managed by Cisco Unified CME.
From Cisco Unified CME Release 11.6 onwards, Local Transcoding Interface (LTI) based transcoding is supported on Cisco 4000 series ISR. LTI includes an internal API that accesses digital signal processor (DSP) resources. This API does not require the use of Skinny Client Control Protocol (SCCP) based configuration for transcoding to work.
LTI-based transcoding is an alternative to SCCP-based transcoding. The LTI-based transcoding configures transcoding functionality only on the specific Unified CME router. Unlike the SCCP-based transcoding, other Unified CME routers cannot leverage the transcoding capabilities configured on a specific Unified CME router. That is, transcoding resources (DSPFARM) are required to be co-located with Unified CME router for LTI-based configuration to work. When both LTI-based and SCCP-based transcoding are configured, LTI takes precedence.
With LTI-based transcoding, internal APIs are used to access DSP resources for transcoding. The TCP sockets are not opened and no registration is used. Also, you need to configure only the DSPFARM profile configuration.
Voice Class Codec (VCC) is supported with LTI-based Transcoding on Cisco 4000 Series ISR, and is an optional configuration. A VCC defines the codec preference order. When a voice class codec is applied to a dial peer, the preference order defined in the voice class codec is followed.
LTI infrastructure supports the features SIP-to-SIP line to trunk transcoding, DTMF Interworking (with in-band on the trunk and rtp-nte on the line), and mid-call transcoder invocation and deletion with call transfer. Features such as Shared Line, Call Park, Call Pickup, iDivert, and so on are not supported with LTI-based transcoding.
A situation in which transcoding resources may be used is when you use the codec command to select the G.729r8 codec to help save network bandwidth for a remote IP phone. If a conference is initiated, all phones in the conference switch to G.711 mu-law. To allow the phone to retain its G.729r8 codec setting when joined to a conference, you can use the codec g729r8 dspfarm-assist command to specify that this phone’s calls should use the resources of a DSP farm for transcoding. For example, there are two remote phones (A and B) and a local phone (C) that initiates a conference with them. Both A and B are configured to use the G.729r8 codec with the assistance of the DSP-farm transcoder. In the conference, the call leg from C to the conference uses the G.711 mu-law codec, and the call legs from A and B to the Cisco Unified CME router use the G.729r8 codec.
Consider your options carefully when deciding to use the codec g729r8 dspfarm-assist command. The benefit is that it allows calls to use the G.729r8 codec on the call leg between the IP phone and the Cisco Unified CME router, which saves network bandwidth. The disadvantage is that for situations requiring G.711 codecs, such as conferencing and Cisco Unity Express, DSP resources that are possibly scarce are used to transcode the call, and delay is introduced while voice is shuttled to and from the DSP. In addition, the overuse of this feature can mask configuration errors in the codec selection mechanisms involving dial peers and codec lists.
Therefore, we recommend using the codec g729r8 dspfarm-assist command sparingly and only when absolutely required for bandwidth savings or when you know the phone will be participating very little, if at all, in calls that require a G.711 codec.
Because of how Cisco Unified CME uses voice channels with Skinny Client Control Protocol (SCCP) endpoints, you must configure at least two available transcoding sessions when establishing a call that requires transcoding configured with the codec g729r8 dspfarm-assist command. Only one session is used after the voice path is established with transcoding. However, during the SCCP manipulations, a temporary session may be allocated. If this temporary session cannot be allocated, the transcoding request is not honored, and the call continues with the G.711 codec.
If the codec g729r8 dspfarm-assist command is configured for a phone and a DSP resource is not available when needed for transcoding, a phone registered to the local Cisco Unified CME router will use G.711 instead of G.729r8. This is not true for nonSCCP call legs; if DSP resources are not available for the transcoding required for a conference, for example, the conference is not created.
Cisco Unified CME uses the secure transcoding DSP farm capability only in the case described in Transcoding When a Remote Phone Uses G.729r8. If a call using the codec g729r8 dspfarm-assist command is secure, Cisco Unified CME looks for a secure transcoding resource. If it cannot find one, transcoding is not done. If the call is not secure, Cisco Unified CME looks for a nonsecure transcoding resource. If it cannot find one, Cisco Unified CME looks for a secure transcoding resource. Even if Cisco Unified CME uses a secure transcoding resource, the call is not secure, and a more expensive secure DSP Farm resource is not needed for a nonsecure call because Cisco Unified CME cannot find a less expensive nonsecure transcoder.
This section contains the following tasks:
To determine if that there are enough DSPs available on your router for transcoding services, perform the following steps.
|
Step 1 |
Use the show voice dsp command to display current status of digital signal processor (DSP) voice channels. |
|
Step 2 |
Use the show sdspfarm sessions command to display the number of transcoder sessions that are active. |
|
Step 3 |
Use the show sdspfarm units command to display the number of DSP farms that are configured. |
DSPs can reside directly on any one of the following:
A voice network module, such as the NM-HD-2VE,
PVDM2s that are installed in a voice network module, such as the NM-HDV2. A single network module can hold up to five PVDMs.
PVDM2s that are installed directly onto the motherboard, such as on the Cisco 2800 and 3800 series voice gateway routers.
You must determine the number of PVDM2s or network modules that are required to support your conferencing and transcoding services and install the modules on your router.
SUMMARY STEPS
Determine performance requirements.
Determine the number of DSPs that are required.
Determine the number of DSPs that are supportable
Verify your solution.
Install hardware.
DETAILED STEPS
|
Step 1 |
Determine the number of transcoding sessions that your router must support. |
|
Step 2 |
Determine the number of DSPs that are required to support transcoding sessions. See Table 5 and Table 6 in the “Allocation of DSP Resources” section of the “Configuring Enhanced Conferencing and Transcoding for Voice Gateway Routers” chapter of the Cisco Unified Communications Manager and Cisco IOS Interoperability Guide. If voice termination is also required, determine the additional number of DSPs required. For example: 16 transcoding sessions (30-ms packetization) and 4 G.711 voice calls require two DSPs. |
|
Step 3 |
Determine the maximum number of NMs or NM farms that your router can support by using Table 4 in the “Allocation of DSP Resources” section of the “Configuring Enhanced Conferencing and Transcoding for Voice Gateway Routers” chapter of the Cisco Unified Communications Manager and Cisco IOS Interoperability Guide. |
|
Step 4 |
Ensure that your requirements fall within router capabilities, taking into account whether your router supports multiple NMs or NM farms. If necessary, reassess performance requirement. |
|
Step 5 |
Install PVDMs, NMs, and NM farms as needed. See the Connecting Voice Network Modules chapter in the Cisco Network Modules Hardware Installation Guide. |
Perform one of the following options, depending on the type of network module to be configured:
To set up DSP farms on NM-HDs and NM-HDV2s, see Configure DSP Farms for NM-HDs and NM-HDV2s.
To set up DSP farms for NM-HDVs, see Configure DSP Farms for NM-HDVs.
| Command or Action | Purpose | |||
|---|---|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
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Step 2 |
configure terminal Example: |
Enters global configuration mode. |
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|
Step 3 |
voice-card slot Example: |
Enters voice-card configuration mode for the network module on which you want to enable DSP-farm services. |
||
|
Step 4 |
dsp services dspfarm Example: |
Enables DSP-farm services for the voice card. |
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Step 5 |
exit Example: |
Exits voice-card configuration mode. |
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|
Step 6 |
sccp local interface-type interface-number Example: |
Selects the local interface that the SCCP applications (transcoding and conferencing) should use to register with Cisco Unified CME.
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|
Step 7 |
sccp ccm ip-address identifier identifier-number Example: |
Specifies the Cisco Unified CME address.
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|
Step 8 |
sccp Example: |
Enables SCCP and its associated transcoding and conferencing applications. |
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|
Step 9 |
sccp ccm group group-number Example: |
Creates a Cisco Unified CME group and enters SCCP configuration mode for Cisco Unified CME.
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Step 10 |
bind interface interface-type interface-number Example: |
(Optional) Binds an interface to a Cisco Unified CME group so that the selected interface is used for all calls that belong to the profiles that are associated to this Cisco Unified CME group.
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Step 11 |
associate ccm identifier-number priority priority-number Example: |
Associates a Cisco Unified CME router with a group and establishes its priority within the group.
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Step 12 |
associate profile profile identifier register device-name Example: |
Associates a DSP farm profile with a Cisco Unified CME group.
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Step 13 |
keepalive retries number Example: |
Sets the number of keepalive retries from SCCP to Cisco Unified CME.
|
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Step 14 |
switchover method [ graceful | immediate] Example: |
Sets the switchover method that the SCCP client uses when its communication link to the active Cisco Unified CME system goes down.
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Step 15 |
switch back method { graceful | guard timeout-guard-value | immediate | uptime uptime-timeout-value} Example: |
Sets the switch back method that the SCCP client uses when the primary or higher priority Cisco Unified CME becomes available again.
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Step 16 |
switchback interval seconds Example: |
Sets the amount of time that the DSP farm waits before polling the primary Cisco Unified CME system when the current Cisco Unified CME switchback connection fails.
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Step 17 |
exit Example: |
Exits SCCP configuration mode. |
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Step 18 |
dspfarm profile profile-identifier transcode [ security] Example: |
Enters DSP farm profile configuration mode and defines a profile for DSP farm services.
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Step 19 |
trustpoint trustpoint-label Example: |
(Optional) Associates a trustpoint with a DSP farm profile. |
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Step 20 |
codec codec-type Example: |
Specifies the codecs supported by a DSP farm profile.
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Step 21 |
maximum sessions number Example: |
Specifies the maximum number of sessions that are supported by the profile.
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Step 22 |
associate application sccp Example: |
Associates SCCP with the DSP farm profile. |
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|
Step 23 |
end Example: |
Returns to privileged EXEC mode. |
To register the DSP Farm to Cisco Unified CME in secure mode, see Register the DSP Farm with Cisco Unified CME 4.2 or a Later Version in Secure Mode.
| Command or Action | Purpose | |||
|---|---|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
||
|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
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|
Step 3 |
voice-card slot Example: |
Enters voice-card configuration mode and identifies the slot in the chassis in which the NM-HDV or NM-HDV farm is located. |
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|
Step 4 |
dsp services dspfarm Example: |
Enables DSP-farm services on the NM-HDV or NM-HDV farm. |
||
|
Step 5 |
exit Example: |
Returns to global configuration mode. |
||
|
Step 6 |
sccp local interface-type interface-number Example: |
Selects the local interface that the SCCP applications (transcoding and conferencing) should use to register with Cisco Unified CME.
|
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|
Step 7 |
sccp ccm ip-address priority priority-number Example: |
Specifies the Cisco Unified CME address.
|
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|
Step 8 |
sccp Example: |
Enables SCCP and its associated transcoding and conferencing applications. |
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|
Step 9 |
dsp farm transcoder maximum sessions number Example: |
Specifies the maximum number of transcoding sessions to be supported by the DSP farm. A DSP can support up to four transcoding sessions.
|
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|
Step 10 |
dspfarm Example: |
Enables the DSP farm. |
||
|
Step 11 |
end Example: |
Returns to privileged EXEC mode. |
To determine the maximum number of transcoder sessions that can occur at one time perform the following steps.
|
Step 1 |
Use the dspfarm transcoder maximum sessions command to set the maximum number of transcoder sessions you have configured. |
|
Step 2 |
Use the show sdspfarm sessions command to display the number of transcoder sessions that are active. |
|
Step 3 |
Use the show sdspfarm units command to display the number of DSP farms that are configured. |
|
Step 4 |
Obtain the maximum number of transcoder sessions by multiplying the number of transcoder sessions from Step 2 (configured in Step 1 using the dspfarm transcoder maximum sessions command) by the number of DSP farms from Step 3. |
Note |
You can unregister all active calls’ transcoding streams with the sdspfarm unregister force command. |
Identify the MAC address of the SCCP client interface. For example, if you have the following configuration:
interface FastEthernet 0/0
ip address 10.5.49.160 255.255.0.0
.
.
.
sccp local FastEthernet 0/0
sccpThe show interface FastEthernet 0/0 command will yield a MAC address. In the following example, the MAC address of the Fast Ethernet interface is 000a.8aea.ca80:
Router# show interface FastEthernet 0/0
.
.
.
FastEthernet0/0 is up, line protocol is up
Hardware is AmdFE, address is 000a.8aea.ca80 (bia 000a.8aea.ca80) | Command or Action | Purpose | |
|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
|
Step 3 |
telephony-service Example: |
Enters telephony-service configuration mode. |
|
Step 4 |
ip source-address ip-address [ port port] [ any-match | strict-match] Example: |
Enables a router to receive messages from Cisco Unified IP phones through the router's IP addresses and ports.
|
|
Step 5 |
sdspfarm units number Example: |
Specifies the maximum number of DSP farms that are allowed to be registered to the SCCP router.
|
|
Step 6 |
sdspfarm transcode sessions number Example: |
Specifies the maximum number of transcoder sessions for G.729 allowed by the Cisco Unified CME router.
|
|
Step 7 |
sdspfarm tag number device-name Example:or |
Permits a DSP farm unit to be registered to Cisco Unified CME and associates it with an SCCP client interface's MAC address.
|
|
Step 8 |
end Example: |
Returns to privileged EXEC mode. |
You must configure the Media Encryption Secure Real-Time Transport Protocol (SRTP) feature in the Cisco Unified CME 4.2 and later versions, making it a secure Cisco Unified CME, before it can host a secure DSP farm. For information on configuring a secure Cisco Unified CME, see Configure Security.
To ensure continued support for existing DSP farms for NM-HDVs configured after upgrading the Cisco IOS software on your Cisco router, perform the following steps.
Note |
Perform this task if previously-configured DSP farms for NM-HDVs fail to register to Cisco Unified CME after you upgrade the Cisco IOS software release. |
Confirm that device name for a dspfarm tag in telephony-service configuration is lower case by using the show -running configuration command.
Example:
Router#show-running configuration
Building configuration...
.
.
.
!
telephony-service
max-ephones 2
max-dn 20
ip source-address 142.103.66.254 port 2000
auto assign 1 to 2
system message Your current options
sdspfarm units 2
sdspfarm transcode sessions 16
sdspfarm tag 1 mtp00164767cc20 !<===Device name is MAC address with lower-case “mtp” prefix
.
.
.
| Command or Action | Purpose | |
|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
|
Step 3 |
no sdspfarm tag number Example: |
Disables the DSP farm. |
|
Step 4 |
sdspfarm tag number device-name Example: |
Permits a digital-signal-processor (DSP) farm to be to registered to Cisco Unified CME and associates it with a SCCP client interface's MAC address.
|
|
Step 5 |
dspfarm Example: |
Enables the DSP farm. |
|
Step 6 |
end Example: |
Returns to privileged EXEC mode. |
| Command or Action | Purpose | |
|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
|
Step 3 |
no dspfarm Example: |
Disables the DSP farm. |
|
Step 4 |
dspfarm transcoder maximum sessions number Example: |
Specifies the maximum number of transcoding sessions to be supported by the DSP farm. |
|
Step 5 |
dspfarm Example: |
Enables the DSP farm. |
|
Step 6 |
end Example: |
Returns to privileged EXEC mode. |
| Command or Action | Purpose | |
|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
|
Step 3 |
sccp ip precedence value Example: |
(Optional) Sets the IP precedence value to increase the priority of voice packets over connections controlled by SCCP. |
|
Step 4 |
dspfarm rtp timeout seconds Example: |
(Optional) Configures the Real-Time Transport Protocol (RTP) timeout interval if the error condition "RTP port unreachable" occurs. |
|
Step 5 |
dspfarm connection interval seconds Example: |
(Optional) Specifies how long to monitor RTP inactivity before deleting an RTP stream. |
|
Step 6 |
end Example: |
Returns to privileged EXEC mode. |
To verify that the DSP farm is registered and running, perform the following steps in any order.
|
Step 1 |
Use the show sccp [ statistics | connections] command to display the SCCP configuration information and current status. Example:Use the show sccp connections command to display information about the connections controlled by the SCCP transcoding and conferencing applications. In the following example, the secure value of the stype field indicates that the connection is encrypted: |
|
Step 2 |
Use the show sdspfarm units command to display the configured and registered DSP farms. Example: |
|
Step 3 |
Use the show sdspfarm sessions command to display the transcoding streams. Example: |
|
Step 4 |
Use the show sdspfarm sessions summary command to display a summary view the transcoding streams. Example: |
|
Step 5 |
Use the show sdspfarm sessions active command to display the transcoding streams for all active sessions. Example: |
|
Step 6 |
Use the show sccp connections details command to display the SCCP connections details such as call-leg details. Example: |
|
Step 7 |
Use the debug sccp { all | errors | events | packets | parser} command to set debugging levels for SCCP and its applications. |
|
Step 8 |
Use the debug dspfarm { all | errors | events | packets} command to set debugging levels for DSP-farm service. |
|
Step 9 |
Use the debug ephone mtp command to enable Message Transfer Part (MTP) debugging. Use this debug command with the debug ephone mtp , debug ephone register , debug ephone state , and debug ephone pak commands. |
The DSP farm can reside on the same router with the Cisco Unified CME or on a different router. Some of the steps in the following tasks are optional depending the location of the DSP farm.
The CA server can be the same router as the DSP farm. The DSP farm router can be configured as a CA server. The configuration steps below show how to configure a CA server on the DSP farm router. Additional configurations are required for configuring CA server on an external Cisco router or using a different CA server by itself.
Note |
Skip this procedure if the DSP farm resides on the same router as the Cisco Unified CME. Proceed to the Create a Trustpoint section. |
The CA server automatically creates a trustpoint where the certificates are stored. The automatically created trustpoint stores the CA root certificate.
Cisco Unified CME 4.2 or a later version.
| Command or Action | Purpose | |||||
|---|---|---|---|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
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||||
|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
||||
|
Step 3 |
crypto pki server label Example: |
Defines a label for the certificate server and enters certificate-server configuration mode.
|
||||
|
Step 4 |
database level complete Example: |
(Optional) Controls the type of data stored in the certificate enrollment database. The default if this command is not used is minimal .
|
||||
|
Step 5 |
grant auto Example: |
(Optional) Allows an automatic certificate to be issued to any requester. The recommended method and default if this command is not used is manual enrollment.
|
||||
|
Step 6 |
database url root-url Example: |
(Optional) Specifies the location where all database entries for the certificate server are to be written out. If this command is not specified, all database entries are written to NVRAM.
|
||||
|
Step 7 |
no shutdown Example: |
(Optional) Enables the CA.
|
||||
|
Step 8 |
exit Example: |
Exits certificate-server configuration mode. |
||||
|
Step 9 |
crypto pki trustpoint label Example: |
(Optional) Declares a trustpoint and enters ca-trustpoint configuration mode.
|
||||
|
Step 10 |
revocation-check crl Example: |
(Optional) Checks the revocation status of a certificate and specifies one or more methods to check the status. If a second and third method are specified, each method is used only if the previous method returns an error, such as a server being down.
|
||||
|
Step 11 |
rsakeypair key-label Example: |
(Optional) Specifies an RSA key pair to use with a certificate.
|
The trustpoint stores the digital certificate for the DSP farm. To create a trustpoint, perform the following procedure:
Cisco Unified CME 4.2 or a later version.
| Command or Action | Purpose | |||
|---|---|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
||
|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
||
|
Step 3 |
crypto pki trustpoint label Example: |
Declares the trustpoint that your RA mode certificate server should use and enters CA-trustpoint configuration mode.
|
||
|
Step 4 |
enrollment url ca-url Example: |
Specifies the enrollment URL of the issuing CA certificate server (root certificate server).
|
||
|
Step 5 |
serial-number none Example: |
Specifies whether the router serial number should be included in the certificate request.
|
||
|
Step 6 |
fqdn none Example: |
Specifies a fully qualified domain name (FQDN) that will be included as "unstructuredName" in the certificate request.
|
||
|
Step 7 |
ip-address none Example: |
Specifies a dotted IP address or an interface that will be included as "unstructuredAddress" in the certificate request.
|
||
|
Step 8 |
subject-name [ x.500-name] Example: |
Specifies the subject name in the certificate request.
|
||
|
Step 9 |
revocation-check none Example: |
(Optional) Checks the revocation status of a certificate and specifies one or more methods to check the status. If a second and third method are specified, each method is used only if the previous method returns an error, such as a server being down.
|
||
|
Step 10 |
rsakeypair key-label Example: |
(Optional) Specifies an RSA key pair to use with a certificate.
|
Cisco Unified CME 4.2 or a later version.
| Command or Action | Purpose | |||
|---|---|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
||
|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
||
|
Step 3 |
crypto pki authenticate trustpoint-label Example: |
Retrieves the CA certificate and authenticates it. Checks the certificate fingerprint if prompted.
|
||
|
Step 4 |
crypto pki enroll trustpoint-label Example: |
Enrolls with the CA and obtains the certificate for this trustpoint.
|
The DSP farm router and Cisco Unified CME router exchanges certificates during the registration process. These certificates are digitally signed by the CA server of the respective router. For the routers to accept each others digital certificate, they should have the CA root certificate of each other. Manually copy the CA root certificate of the DSP farm and Cisco Unified CME router to each other.
| Command or Action | Purpose | |||
|---|---|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
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|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
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Step 3 |
crypto pki trustpoint label Example: |
Declares the trustpoint that your RA mode certificate server should use and enters CA-trustpoint configuration mode.
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|
Step 4 |
enrollment terminal Example: |
Specifies manual cut-and-paste certificate enrollment. |
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|
Step 5 |
crypto pki export trustpoint pem terminal Example: |
Exports certificates and RSA keys that are associated with a trustpoint in a privacy-enhanced mail (PEM)-formatted file. |
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|
Step 6 |
crypto pki authenticate trustpoint-label Example: |
Retrieves the CA certificate and authenticates it. Checks the certificate fingerprint if prompted.
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|
Step 7 |
You will be prompted to enter the CA certificate. Cut and paste the base 64 encoded certificate at the command line, then press Enter, and type "quit". The router prompts you to accept the certificate. Enter "yes" to accept the certificate. |
Completes the copying of the CA root certificate of the DSP farm router to the Cisco Unified CME router. |
Repeat the steps in the Copy the CA Root Certificate of the DSP Farm Router to the Cisco Unified CME Router section in the opposite direction, that is, from Cisco Unified CME router to the DSP farm router.
Prerequisites
Cisco Unified CME 4.2 or a later version.
| Command or Action | Purpose | |||
|---|---|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
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|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
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|
Step 3 |
telephony-service Example: |
Enters telephony-service configuration mode. |
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|
Step 4 |
sdspfarm units number Example: |
Specifies the maximum number of digital-signal-processor (DSP) farms that are allowed to be registered to the Skinny Client Control Protocol (SCCP) server. |
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|
Step 5 |
sdspfarm transcode sessions number Example: |
Specifies the maximum number of transcoding sessions allowed per Cisco Unified CME router.
|
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|
Step 6 |
sdspfarm tag number device-name Example: |
Permits a DSP farm to register to Cisco Unified CME and associates it with a SCCP client interfaces MAC address.
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|
Step 7 |
exit Example: |
Exits telephony-service configuration mode. |
Use the show sdspfarm units command to verify that the DSP farm is registering with Cisco Unified CME. Use the show voice dsp group slot command to show the status of secure conferencing.
Prerequisites
Cisco Unified CME 4.2 or a later version.
Router# show sdspfarm units
mtp-2 Device:choc2851SecCFB1 TCP socket:[1] REGISTERED
actual_stream:8 max_stream 8 IP:10.1.0.20 37043 MTP YOKO keepalive 17391
Supported codec: G711Ulaw
G711Alaw
G729
G729a
G729ab
GSM FR
max-mtps:2, max-streams:60, alloc-streams:18, act-streams:0
Router# show voice dsp group slot 1
dsp 13:
State: UP, firmware: 4.4.706
Max signal/voice channel: 16/16
Max credits: 240
Group: FLEX_GROUP_VOICE, complexity: FLEX
Shared credits: 180, reserved credits: 0
Signaling channels allocated: 2
Voice channels allocated: 0
Credits used: 0
Group: FLEX_GROUP_XCODE, complexity: SECURE MEDIUM
Shared credits: 0, reserved credits: 60
Transcoding channels allocated: 0
Credits used: 0
dsp 14:
State: UP, firmware: 1.0.6
Max signal/voice channel: 16/16
Max credits: 240
Group: FLEX_GROUP_CONF, complexity: SECURE CONFERENCE
Shared credits: 0, reserved credits: 240
Conference session: 1
Credits used: 0
| Command or Action | Purpose | |
|---|---|---|
|
Step 1 |
enable Example: |
Enables privileged EXEC mode.
|
|
Step 2 |
configure terminal Example: |
Enters global configuration mode. |
|
Step 3 |
voice-card slot Example: |
Enters voice-card configuration mode for the network module on which you want to enable DSP-farm services. |
|
Step 4 |
dsp services dspfarm Example: |
Enables DSP-farm services for the voice card. |
|
Step 5 |
exit Example: |
Exits voice-card configuration mode. |
|
Step 6 |
dspfarm profile profile-identifier transcode [ universal] Example: |
Enters DSP farm profile configuration mode and defines a profile for DSP farm services.
|
|
Step 7 |
codec codec-type Example: |
Specifies the codecs supported by a DSP farm profile.
|
|
Step 8 |
maximum sessions number Example: |
Specifies the maximum number of sessions that are supported by the profile.
|
|
Step 9 |
associate application CUBE Example: |
Associates CUBE with the DSP farm profile. |
|
Step 10 |
no shutdown Example: |
Enables the DSP farm profile. |
|
Step 11 |
end Example: |
Returns to privileged EXEC mode. |
Note |
You can use the command show dspfarm profile profile-number to verify the configured DSP farm profiles. Use the command to verify if the profile status is UP, and the application status is ASSOCIATED. |
The following example sets up a DSP farm of 4 DSPs to handle up to 16 sessions (4 sessions per DSP) on a router with an IP address of 10.5.49.160 and a priority of 1 among other servers.
voice-card 1
dsp services dspfarm
exit
sccp local FastEthernet 0/0
sccp
sccp ccm 10.5.49.160 priority 1
dspfarm transcoder maximum sessions 16
dspfarm
telephony-service
ip source-address 10.5.49.200 port 2000
sdspfarm units 4
sdspfarm transcode sessions 40
sdspfarm tag 1 mtp000a8eaca80
sdspfarm tag 2 mtp123445672012The following example sets up six transcoding sessions on a router with one DSP farm, an IP address of 10.5.49.160, and a priority of 1 among servers.
voice-card 1
dsp services dspfarm
sccp local FastEthernet 0/1
sccp
sccp ccm 10.5.49.160 identifier 1
sccp ccm group 123
associate ccm 1 priority
associate profile 1 register mtp123456792012
keepalive retries 5
switchover method immediate
switchback method immediate
switchback interval 5
dspfarm profile 1 transcode
codec g711ulaw
codec g711alaw
codec g729ar8
codec g729abr8
maximum sessions 6
associate application sccp
telephony-service
ip source-address 10.5.49.200 port 2000
sdspfarm units 1
sdspfarm transcode sessions 40
sdspfarm tag 1 mtp000a8eaca80
sdspfarm tag 2 mtp123445672012The following example configures Cisco Unified CME router address 10.100.10.11 port 2000 to be the farm host using the DSP farm at mtp000a8eaca80 to allow for a maximum of 1 DSP farm and 16 transcoder sessions.
telephony-service
ip source address 10.100.10.11 port 2000
sdspfarm units 1
sdspfarm transcode sessions 16
sdspfarm tag 1 mtp000a8eaca80The following example configures Cisco Unified CME router for LTI-based transcoding.
voice-card 0
dsp services dspfarm
!--- Dspfarm profile configuration with associate
!--- application CUBE for LTI transcoding.
dspfarm profile 1 transcode universal
codec g729ar8
codec g729br8
codec g711alaw
codec g711ulaw
codec g729r8
maximum sessions 12
associate application CUBE
!--- Only dspfarm profile configurations are needed for
!--- LTI-based transcoding. All the SCCP-based transcoding
!--- features will be supported with LTI-based transcoding.The following example configures voice class codec under a dial peer on Unified CME.
voice class codec 10
codec preference 1 g711alaw
codec preference 2 g711ulaw bytes 80
codec preference 3 g723ar53
codec preference 4 g723ar63 bytes 144
codec preference 5 g723r53
codec preference 6 g723r63 bytes 120
codec preference 7 g726r16
codec preference 8 g726r24
codec preference 9 g726r32 bytes 80
codec preference 10 g728
codec preference 11 g729br8
codec preference 12 g729r8 bytes 50
dial-peer voice 100 voip
voice-class codec 10
You can also configure voice class codec under a voice register pool on Unified CME.
voice register pool 1
id mac 0030.94C2.A22A
preference 5
cor incoming call91 1 91011
translate-outgoing called 1
proxy 192.0.2.0 preference 1 monitor probe icmp-ping
alias 1 94... to 91011 preference 8
voice-class codec 10
Music on Hold
Music on hold can require transcoding resources. See Music on Hold.
Teleworker Remote Phones
Transcoding has benefits and disadvantages for remote teleworker phones. See the discussion in Configuring Phones to Make Basic Calls.
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
|
Feature Name |
Cisco Unified CME Version |
Feature Information |
|---|---|---|
|
LTI-based Transcoding |
11.6 |
Support for LTI-based Transcoding on Cisco 4000 Series ISR. |
|
Secure Transcoding |
4.2 |
Secure transcoding for calls using the codec g729r8 dspfarm-assist command was introduced. |
|
Transcoding Support |
3.2 |
Transcoding between G.711 and G.729 was introduced. |
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