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Commands for Adding, Configuring, and Displaying Voice Connections

This section describes the commands you use to add, configure, and display voice connections on the VISM:

  • dspvismparam—Displays the VISM configuration, including the voice mode (VoIP or VoAAL2).

  • cnfvismmode—Changes the VISM configuration, including the voice mode.

  • addport—Creates a logical port on the VISM. This command must be used only once on the VISM.

  • delport—Removes the logical port from the VISM.

  • dspport—Lists the logical port on the VISM.

  • addrscprtn—Creates a resource partition. This command must be used only once on the VISM.

  • delrscprtn—Removes a resource partition.

  • dsprscprtn—Displays the resource partition configuration.

  • cnflnsig—Changes a line's signaling type.

  • dsplndsp—Displays the line digital signal processor (DSP) configuration, including echo cancellation and voice activity detection (VAD).

  • cnfecanenable—Enables or disables a line's echo cancellation.

  • cnfecanrec—Sets a line's residual echo control.

  • cnfecantail—Sets the maximum echo cancellation tail length between 24 and 128 milliseconds.

  • cnfcompvad—Enables VAD on a line.

  • addendpt—Creates an endpoint on the VISM.

  • delendpt—Removes an endpoint from the VISM.

  • addendpts—Adds multiple, contiguous endpoints on the VISM.

  • delendpts—Removes multiple, contiguous endpoints from the VISM.

  • dspendpts—Lists all endpoints on the VISM.

  • dspendpt—Lists detailed information for an endpoint.

  • addcon—Creates a new voice connection on the VISM.

  • delcon—Removes a voice connection from the VISM.

  • dspcons—Lists summary status and configuration information for all connections on the VISM.

  • dspcon—Lists detailed configuration information for a connection.

  • addcid—Creates a new CID on the VISM that associates a connection with an endpoint.

  • delcid—Removes a CID from the VISM and disassociates a connection with an endpoint.

  • dspcids—Lists configuration information for all CIDs on a connection.

  • dspcid—Lists configuration information for a CID.

Display VISM Parameter Command

The dspvismparam command shows the voice mode configuration for the VISM. Use this command to learn whether the VISM is configured for VoIP or VoAAL2 services. You can change the VISM's voice mode using the cnfvismmode command. Example 22-1 shows the dspvismparam output.

Example 22-1 dspvismparam Output

smoke.1.3.VISM8.a > dspvismparam
VISM mode:                  aal2Trunking
CAC flag:                   enable
DS0s available:             240
Template number:            2
Percent of functional DSPs: 100
IP address:       
Subnet mask       
RTCP report interval:       1000
RTP receive timer:          disable
ControlPrecedence/Tos:      0x60
BearerPrecedence/Tos:       0xa0
Aal2 muxing status:         disable
Tftp Server Dn              TFTPDOMIAN

The information shown in the dspvismparam output includes the following:

  • VISM mode—Either AAL2 trunking or VoIP switching.

  • Connection Admission Control (CAC) flag—Specifies whether CAC is enabled or disabled on the VISM. This field applies only to VoIP mode.

  • DS0s available—The number of channels available on the card. This number depends on the card type (T1 or E1) and the template in use. This field applies only to VoAAL2 mode.

  • Template number—Specifies which template (1 or 2) is configured for the VISM. Template number 1 supports G.711u, G.711a, G.729a, G.729ab, G.726/32, and clear-channel codecs. Template 1 is not allowed in VoIP mode and reduces the number of channels supported on the card. Template number 2 supports G.711u, G.711a, and clear channel only. You can change the template using the cnfcodectmpl command.


    Template number 1 in VISM Release 2.1 supports G.711u, G.711a, G.729a, G.729ab, G.726/32, and clear-channel codecs, plus G.726 16K, 24K, 32K, and 40K codecs.

  • Percent of functional DSPs—The percentage of DSPs that are fully functional on the VISM.

  • IP address—The IP address of the VISM used in VoIP mode.

  • Subnet mask—The subnet mask that the VISM uses in VoIP mode.

  • Real-time Transport Control Protocol (RTCP) report interval—The amount of time between RTCP messages for VoIP.

  • Real-time Transport Protocol (RTP) receive timer—The amount of time between expected RTP messages.

  • Control precedence—Control precedence for IP packets is a type of service (ToS) that conforms to RFC 1349. It determines which IP packets have higher priority as defined by the bearer precedence.

  • Bearer precedence—Bearer precedence for IP packets conforms to RFC 791. It can be in the priority range of 0 to 7. You can adjust the precedence of the bearer IP packets as follows: 0 = low priority, 7 = high priority. The priority levels help ensure timely delivery of all traffic in a heterogeneous network.

  • AAL2 multiplexing status—Specifies whether multiple voice streams can be multiplexed onto the same AAL2 connection. You can change this field using the cnfaal2subcellmuxing command.

  • TFTP server domain name—The domain name of the TFTP server.

Configure VISM Mode Command

The cnfvismmode command changes the VISM card's voice mode. Use this command if you need to change the VISM to or from VoIP or VoAAL2.

Here is the cnfvismmode command syntax:

cnfvismmode <mode>

mode is either 1 for VoIP or 2 for VoAAL2.

For example, type cnfvismmode 2 to change the mode from VoIP to VoAAL2.

Add Port Command

The addport command creates a logical interface between the VISM and the PXM1. You must type this command before you add any endpoints, connections, or CIDs on the VISM. This command has no required or optional parameters.

Display Port Command

The dspport command shows the VISM port status. Use this command to verify that the port was added. You can delete the port using the delport command.

Example 22-2 shows the dspport output.

Example 22-2 dspport Output

smoke.1.3.VISM8.a > dspport
  vismPortNum:           1
  vismPortRowStatus:     add
  vismPortSpeed:         60000
  vismPortState:         active

The information shown in the dspport output includes the following:

  • Port number—Always 1.

  • Port row status—The row status is add unless the port is modified. In that case, the status is mod.

  • Port speed—Indicates the amount of voice traffic that the VISM can send to the PXM1.

  • Port state—In most cases, the port state is active.

Add Resource Partition Command

The addrscprtn command creates resource partitions on the VISM port. You must issue this command after adding the port and before you add any endpoints, connections, or CIDs to the VISM. You can remove the resource partition using the delrscprtn command.

Here is the addrscprtn command syntax:

addrscprtn <controller ID>

controller ID is 1 for Portable AutoRoute (PAR).

For example, type addrscprtn 1 to add the PAR resource partition to the VISM port.

Display Resource Partition Command

The dsprscprtn command shows the resource partition configuration. Note that the resource partition cannot be configured. Example 22-3 shows the dsprscprtn output.

Example 22-3 dsprscprtn Output

smoke.1.1.VISM8.a > dsprscprtn
  vismResPartPortNum:        1
  vismResPartCtrlrNum:       par
  vismResPartRowStatus:      add
  vismResPartNumOfLcnAvail:  72
  vismResPartLcnLow:         131
  vismResPartLcnHigh:        510
  vismResPartIngrPctBW:      100
  vismResPartEgrPctBW:       100
  vismResPartCtrlrID:        1

The information shown in the dsprscprtn output includes the following:

  • Port number—Always 1.

  • Controller number—Always par.

  • Row status—Always add.

  • Number of logical connection numbers (LCNs) available—The number of channels that you can add on the VISM.

  • LCN low—The minimum LCN or channel number allowed.

  • LCN high—The maximum LCN or channel number allowed.

  • Ingress percent bandwidth—The percentage of the ingress port bandwidth allocated to this resource partition.

  • Egress percent bandwidth—The percentage of the egress port bandwidth allocated to this resource partition.

  • Controller ID—Always 1 for PAR.

Configure Line Signaling Command

The cnflnsig command sets the signaling method of a T1 or E1 line. Use this command to enable CAS or CCS signaling on the line. Even if the physical line is set for CCS using the cnfln command, you must use the cnflnsig command to set up the signaling method. Use the dspln command to learn the line-signaling configuration.

Here is the cnflnsig command syntax:

cnflnsig <line number> <signaling type>

The parameter options are as follows:

  • line number—The T1 or E1 line number. 1 to 8.

  • signaling type—The voice signaling type. 1 = CAS, 2 = CCS, 3 = no signaling.

For example, type cnflnsig 2 1 to enable CAS signaling on line number 2.

Display Line DSP Command

The dsplndsp command shows the DSP configuration for a line. Use this command to learn the echo cancellation and VAD settings. Example 22-4 shows the dsplndsp output.

Example 22-4 dsplndsp Output

smoke.1.1.VISM8.a > dsplndsp 8
 VismLineNum:      8
 ECANEnable:       enable
 MaximumTail:      32 milliseconds
 ResidualEcho:     SuppressResidual
 VoiceDetection:   Enable

The information shown in the dsplndsp output includes the following:

  • VismLineNum—Represents the VISM card line number.

  • Echo cancel enable—Enabled or disabled. Use the cnfecanenable command to change this field.

  • Maximum tail—The maximum tail length (delay) for the echo canceller. Choices include 24, 32, 48, 64, 80, 96, 112, and 128 milliseconds. Use the cnfecantail command to change this field.

  • Residual echo—The echo canceller's action for residual echo. Residual echo is what is left over after the echo is cancelled due to the echo model's being imperfect. Choices include cancel only, suppress residual, or inject comfort noise. Use the cnfecanrec command to change this field.

  • Voice detection—Specifies whether VAD is enabled or disabled. Use the cnfcompvad command to change this field.

Add Endpoint and Add Endpoints Commands

The addendpt and addendpts commands are used to add new endpoints on the VISM. The addendpt command creates one endpoint, and the addendpts command creates multiple contiguous endpoints. It is recommended that you use the addendpts command to create endpoints on all available channels when you start configuring your VISM. You must add endpoints before adding connections and CIDs to the VISM. Use the delendpt and delendpts commands to delete endpoints on the VISM.

Here is the addendpt command syntax:

addendpt <endpoint number> <DS1 number> <DS0 number>

Here is the addendpts command syntax:

addendpts <endpoint number> <DS1 number> <DS0 number> <number of endpoints>

The parameter options are as follows:

  • endpoint number—Used when you add a CID. 1 to 192 for T1, 1 to 240 for E1.

  • DS1 number—The T1 or E1 line number. 1 to 8.

  • DS0 number—The DS0 or (starting) timeslot number. 1 to 24 for T1, 1 to 31 for non-CAS E1, 1 to 15 and 17 to 31 for CAS E1.

  • number of endpoints (addendpts only)—The number of contiguous endpoints you want to add. 1 to 192 for T1, 1 to 240 for E1.

For example, type addendpt 1 4 8 to add endpoint 1 to timeslot 8 on line 4; type addendpts 2 4 9 10 to add 10 endpoints starting with endpoint number 2 on timeslot 9 on line 4.

Display Endpoints Command

The dspendpts command lists all the endpoints configured on the VISM. Use this command to learn which endpoints exist. Example 22-5 shows the dspendpts output.

Example 22-5 dspendpts Output

smoke.1.3.VISM8.a > dspendpts
  EndptNum Ena/Speed
  -------- --- -----
  1        act/ 64k
  2        act/ 64k
  3        act/ 64k
  4        act/ 64k
  5        act/ 64k
  6        act/ 64k
  7        act/ 64k
  8        act/ 64k
  9        act/ 64k
  10       act/ 64k
  11       act/ 64k
  12       act/ 64k
  13       act/ 64k
  14       act/ 64k
  15       act/ 64k
  16       act/ 64k
  17       act/ 64k
  18       act/ 64k
  19       act/ 64k
  20       act/ 64k
Type <CR> to continue, Q<CR> to stop:

Display Endpoint Command

The dspendpt command shows detailed information about an endpoint. Use this command to learn which line and timeslot an endpoint is associated with. Example 22-6 shows the dspendpt output.

Example 22-6 dspendpt Output

smoke.1.1.VISM8.a > dspendpt 1
  EndptNum:        1
  EndptLineNum:    8
  EndptName:       E1-8/1@cisco.com
  EndptSpeed:      64 kbps
  EndptState:      active
  EndptChannelMap: 2
  EndptEnable:     active
  EndptLoopback:   disabled

The dspendpt output includes the following information:

  • EndptNum—The endpoint number.

  • EndptLineNum—The line an endpoint is associated with.

  • EndptName—The endpoint name in the form line type-line number/endpoint number@domain name. line type is T1 or E1, and domain name is the VISM domain name that is used for VoIP signaling messages. The default domain name is cisco.com. In Example 22-6, E1-8/1@cisco.com is endpoint 1 on E1 line 8.

  • EndptSpeed—The endpoint speed. Either 56 or 64 kbps.

  • EndptState—The endpoint state, usually active.

  • EndptChannel Map—A hexadecimal number representing the timeslot assigned to the endpoint. If you convert this number into a binary number, each bit represents a timeslot. The least-significant digit (on the right) is timeslot 1; the most-significant digit (on the left) is the highest timeslot number. Notice that leading zeros are not shown. In Example 22-6, the channel map is 2, which is a binary 10. This means that timeslot 1 is assigned to this endpoint. (Because this is an E1, timeslot 0, the least-significant bit is reserved for framing.)

  • EndptEnable—Usually active.

  • EndptLoopback—The endpoint loopback state, either enabled or disabled. You can loop the endpoint using the addendptloop command and remove an endpoint using the delendptloop command.

Add Connection Command

The addcon command is used to create a new voice connection on the VISM. You can use the delcon command to remove the connection.

Here is the addcon command syntax:

addcon <local VCI> <preference> <PVC type> <application> <PCR> <mastership>
  [remote connection ID]

The parameter options are as follows:

  • local VCI—The LCN number. You use this number when you configure a CID. 131 to 510.

  • preference—Specifies a primary or secondary channel for redundancy purposes. 1 = primary, 2 = secondary.

  • PVC type—1 = AAL5 used for VoIP and signaling channels, 2 = AAL2 for VoAAL2 channels, 3 = AAL1 (not supported).

  • application—Specifies how the connection is used. 1 = control for VoIP when a separate control channel is used, 2 = bearer for voice traffic, 3 = signaling for VoAAL2.

  • PCR—The connection's Peak Cell Rate (PCR). For connections in which multiple voice circuits are multiplexed onto one connection, you need to calculate the PCR based on the aggregate rate of the supported voice calls. 1 to 75,600 cells per second (cps) for AAL5 bearer PVC, 1 to 24,400 cps for AAL5 control PVC, 1 to 50,000 cps for T1 AAL2 bearer PVC, 1 to 60,000 cps for E1 AAL2 bearer PVC, 1 to 400 cps for signaling PVC in AAL2 trunking mode.

  • mastership—1 = master, 2 = slave. If you are adding a slave connection, you do not need to specify the mastership or the remote connection ID.

  • remote connection ID—The destination connection ID for master connections in the form node name.card slot.port.VPI.VCI. If you are adding a feeder connection to the PXM1, card slot must be 0. If you are adding a local connection to another VISM, port is always 1, VPI is always 0, and VCI is the remote LCN. If you are adding a local connection to an ATM interface, you must specify the port, VPI, and VCI on the ATM side.

Display Connections Command

The dspcons command lists summary status information for all connections on the VISM. Example 22-7 shows the dspcons output.

Example 22-7 dspcons Output

smoke.1.3.VISM8.a > dspcons
 ConnId      ChanNum Status Preference Protection  Active Locking
 -------     ------- ------ ---------- ---------- ------- --------
smoke.   131  Mod           1 unprotected unknown unlock
smoke.   132  Add           1 unprotected unknown unlock
smoke.   133  Add           1 unprotected unknown unlock

The dspcons output includes the following information:

  • Connection ID—The local connection ID in the form node name.card slot.1.0.LCN

  • Channel number—The local VCI or LCN

  • Status—Add or Mod (modify)

  • Preference—Specifies a primary (1) or secondary (2) channel

  • Protection—The redundancy protection type

  • Active—The redundancy state

  • Locking—The redundancy locking

Display Connection Command

The dspcon command shows detailed configuration information for a connection. Example 22-8 shows the dspcon output. There are two pages to the dspcon output; the second page is shown in Example 22-9.

Example 22-8 dspcon Output, Page 1

smoke.1.3.VISM8.a > dspcon 131
 ChanNum:         131
 ChanRowStatus:      Mod
 ChanLocalRemoteLpbkState: Disabled
 ChanTestType:       TestOff
 ChanTestState:      NotInProgress
 ChanRTDresult:      65535 ms
 ChanPortNum:       1
 ChanPvcType:       AAL2
 ChanConnectionType:    PVC
 ChanLocalVpi:       0
 ChanLocalVci:       131
 ChanLocalNSAP:      736d6f6b65000000000000000000000003000100
 ChanRemoteVpi:      0
 ChanRemoteVci:      131
 ChanRemoteNSAP:      736d6f6b65000000000000000000000001000100
 ChanMastership:      Master
 ChanVpcFlag:       Vcc
 ChanConnServiceType:   CBR
 ChanRoutingPriority:   1
 ChanMaxCost:       4294967295
 ChanRestrictTrunkType:  No Restriction
Type <CR> to continue, Q<CR> to stop:

Many of the fields listed in the dspcon output can be modified using a number of configuration commands discussed in this section. Other information in the dspcon output includes the following:

  • RTD result—The result of the most recent round-trip delay test (use the tstdelay command). If the test has never been run, it reports 65,535 milliseconds.

  • Channel local NSAP—The network service access point (NSAP) address uniquely identifies this interface (port) in the network. The 20-byte hexadecimal address has the following fields:

    • The most-significant 8 bytes (16 digits) spell out the node name in ASCII. The connection in Example 22-8 is on node smoke.

    • The card slot number is the fourth byte from the right. The connection in Example 22-8 is on card 3.

    • The port number is the second byte from the right. All VISM connections are on port 1.

Example 22-9 shows the second page of the dspcon output.

Example 22-9 dspcon Output, Page 2

ChanConnPCR:       100
 ChanConnPercentUtil:   100
 ChanPreference:      1
 ChanRemotePCR:      100
 ChanRemotePercentUtil:  100
 ChanProtection:      unprotected
 ChanActivityState:    unknown
 ChanLockingState:     unlock
 ChanApplication:     bearerf
 ChanServiceType:     cbr
 ChanScrIngress:      100
 ChanMbsIngress:      100
 ChanNumNextAvailable: 132

Add CID Command

The addcid command creates a new CID that associates a connection with an endpoint. You can add multiple CIDs to a connection, but each must have a different endpoint and CID. Use the delcid command to delete a CID from the VISM.

Here is the addcid command syntax:

addcid <endpoint number> <LCN> <CID number> <codec type> [profile type]
  [profile number] [VAD] [VAD initialization timer] [echo cancellation]
  [triple redundancy protection] [CAS transport] [DTMF transport] [ICS]
  [packet period]

The parameter options are as follows:

  • endpoint number—The endpoint associated with this CID. Only one CID can be associated with an endpoint. 1 to 192 for T1 cards, 1 to 240 for E1 cards.

  • LCN—The logical connection number. 131 to 510.

  • CID number—The CID must be unique per connection (LCN). 9 to 255.

  • codec type—The voice compression type. 1 = G.711u, 2 = G.711a, 3 = G.726/32, 4 = G.729a, 5 = G.729ab, 6 = clear channel. (VAD must be off when the codec is clear-channel.)

  • profile type—1 = ITU, 3 = custom. This parameter is required if codec type is G.729a/ab.

  • profile number—1, 2, or 7 for ITU. 100 or 101 for custom. Use the dspaal2profile command to see the profile characteristics. Be sure to use a profile that supports the compression type (codec type) you are using. This parameter is required if codec type is G.729a/ab.

  • VAD—Enables or disables VAD. 1 = VAD on, 2 = VAD off (the default).

  • VAD initialization timer—Determines how long to wait after a speech burst before starting VAD. If this time is too short, you might experience clipping. If it is too long, you might not get the bandwidth savings you require. 250 to 65,535 milliseconds.

  • echo cancellation—Enables or disables echo cancellation. 1 = on (default), 2 = off.

  • triple redundancy protection—Enables or disables triple redundancy protection. 1 = on, 2 = off.

  • CAS transport—Enables or disables the transport of CAS signaling bits in the AAL2 traffic stream. 1 = on (default), 2 = off.

  • DTMF transport—Enables or disables the transport of DTMF tones in the AAL2 traffic stream (inband). 1 = on (default), 2 = off.

  • Integrated Communications System (ICS)—1 = enable, 2 = disable.

  • packet period—The amount of time between G.729a packets. 10, 20, 30, or 40 milliseconds.

For example, type 1131 9 1 1 1 1 300 1 2 1 1 1 to create CID number 9 associated with endpoint 1 and LCN 131. This CID is set for G.711u and uses ITU profile number 1.

Display CIDs Command

The dspcids command lists all the CIDs on a specified LCN. Use this command to learn which CIDs are on a connection and how they are configured. Example 22-10 shows the dspcids command output.

Example 22-10 dspcids Output

smoke.1.1.VISM8.a > dspcids 132
LCN CID Endpt Cid  Type3   VAD  Prof  Prof Codec Cas DTMF   ICS  Pkt
Num Num  Num  Status Redun VAD Timer Type  Num  Type   Tran Tran Ecan Enable Per.
--- --- ----- ------ ----- --- ----- ----- ---- ------ ---- ---- ---- ------ ----
132 10     2  active  ena  ena  250   ITU     1 G.711u  ena  ena  ena  Dis     5
132 22     3  active  ena  ena  250   ITU     1 g.711u  ena  ena  ena  Dis     5

The dspcids output shows all the characteristics you set using the addcid command.

Display CID Command

The dspcid command shows the same information as the dspcids output, but for a specific CID. Example 22-11 shows the dspcid output.

Example 22-11 dspcid Output

smoke.1.3.VISM8.a > dspcid 131 9
  LCN number :     131
  CID number:     9
  Endpoint number :  50
  CidRowStatus:    active
  Type3redundancy:   enabled
  VAD:         disabled
  VADInitTimer:    200
  Profile type:    Custom
  Profile number:   100
  Codec type:     clr chan
  Cas transport:    enabled
  DTMF transport:   enabled
  Ecan on/off:     enabled
  ICS enable:     Disabled
  pkt period:     5

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