How to Check I have enough DSP resources on Voice Gateway for 240 SIP Channels

AA BB · ‎04-21-2015

Hi All,

We have new client coming on board and we are planning to acquire 240 (30 X 8) SIP channels which will be used for inbound and outbound calls. We aim to configure SIP trunks on our voice gateways for a specific reason rather than our CUCM. We have two voice gateways 3945 ISR each having Gen3-256 PVDM cards. Voice Gateway A has 2 PRIs installed and voicegateway B has 3 PRIs installed on it. These PRIs serve our existing customers. I know that for these PRIs we must be using some DSP resources for trans-coding and also for other purposes like conferencing, MTP or etc. My first question is if we acquire new 240 SIP trunks and configure on voice gateways, will it consume our DSP resources at all? If yes then how can I make sure that I have enough DSP resources for the new 240 SIP channels and will not affect our current client services? Full details of our current contact center environment are below, its basically UCCE 7.0 but soon will be upgraded to 10.5:

· Two ICM Admin Work Stations A & B co-resident with Web View. ICM version is 7.5.8

· Two Agent PGs side A and side B, each resident with CTIOS Server.

· CVP 7.0(2) i.e. two call Servers / VXML Servers A and B. Each resident with Media Server.

· CVP Ops Console Server

· CVP Port licenses 150

· CVP Call Studio 7.0.(2) (This is just a temporary server for development purpose)

· Two ROGGER Servers A and B

· Two Voice Gateways 3945 each containing PVDM3-256.

· Voice Gateway A has 2 PRIs installed and voice gateway B has 3 PRIs installed.

· CUCM 7.1.3 i.e. One Publisher and Two Subscribers.

· Voice mail through Asterisk

· IP Phone licenses 900 Units.

· 70 Agent concurrent licenses

· Orecx as Call Recording Solution with port mirroring architecture.

Following is show inevntory of voice gateway A & B:

=~=~=~=~=~=~=~=~=~=~=~= PuTTY log 2015.04.21 13:28:52 voice gateway A =~=~=~=~=~=~=~=~=~=~=~=

NAME: "CISCO3945-CHASSIS", DESCR: "CISCO3945-CHASSIS"
PID: CISCO3945-CHASSIS , VID: V01 , SN: FHK1417F0CK

NAME: "Cisco Services Performance Engine 150 for Cisco 3900 ISR on Slot 0", DESCR: "Cisco Services Performance Engine 150 for Cisco 3900 ISR"
PID: C3900-SPE150/K9 , VID: V01 , SN: FOC14163MFS

NAME: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1 on Slot 0 SubSlot 0", DESCR: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1"
PID: VWIC2-2MFT-T1/E1 , VID: V01 , SN: FOC141351FS

NAME: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1 on Slot 0 SubSlot 1", DESCR: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1"
PID: VWIC2-2MFT-T1/E1 , VID: V01 , SN: FOC14134ZVK

NAME: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1 on Slot 0 SubSlot 2", DESCR: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1"
PID: VWIC2-2MFT-T1/E1 , VID: V01 , SN: FOC14134ZTY

NAME: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1 on Slot 0 SubSlot 3", DESCR: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1"
PID: VWIC2-2MFT-T1/E1 , VID: V01 , SN: FOC141350ZU

NAME: "PVDM3 DSP DIMM with 256 Channels on Slot 0 SubSlot 4", DESCR: "PVDM3 DSP DIMM with 256 Channels"
PID: PVDM3-256 , VID: V01 , SN: FOC14071Q25

NAME: "C3900 AC Power Supply 1", DESCR: "C3900 AC Power Supply 1"
PID: PWR-3900-AC , VID: V01 , SN: SNI1353C83F

NAME: "C3900 AC Power Supply 2", DESCR: "C3900 AC Power Supply 2"
PID: PWR-3900-AC , VID: V01 , SN: SNI1351C843

=~=~=~=~=~=~=~=~=~=~=~= PuTTY log 2015.04.21 13:31:08 voice gateway B =~=~=~=~=~=~=~=~=~=~=~=
show invento
IOD-SIL-GWB01#show inventory
NAME: "CISCO3945-CHASSIS", DESCR: "CISCO3945-CHASSIS"
PID: CISCO3945-CHASSIS , VID: V01 , SN: FHK1417F0CJ

NAME: "Cisco Services Performance Engine 150 for Cisco 3900 ISR on Slot 0", DESCR: "Cisco Services Performance Engine 150 for Cisco 3900 ISR"
PID: C3900-SPE150/K9 , VID: V01 , SN: FOC14163M98

NAME: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1 on Slot 0 SubSlot 0", DESCR: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1"
PID: VWIC2-2MFT-T1/E1 , VID: V01 , SN: FOC14134ZZU

NAME: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1 on Slot 0 SubSlot 1", DESCR: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1"
PID: VWIC2-2MFT-T1/E1 , VID: V01 , SN: FOC14125ERQ

NAME: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1 on Slot 0 SubSlot 2", DESCR: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1"
PID: VWIC2-2MFT-T1/E1 , VID: V01 , SN: FOC1413513F

NAME: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1 on Slot 0 SubSlot 3", DESCR: "VWIC2-2MFT-T1/E1 - 2-Port RJ-48 Multiflex Trunk - T1/E1"
PID: VWIC2-2MFT-T1/E1 , VID: V01 , SN: FOC14134ZQW

NAME: "PVDM3 DSP DIMM with 256 Channels on Slot 0 SubSlot 4", DESCR: "PVDM3 DSP DIMM with 256 Channels"
PID: PVDM3-256 , VID: V01 , SN: FOC14071Q1T

NAME: "C3900 AC Power Supply 1", DESCR: "C3900 AC Power Supply 1"
PID: PWR-3900-AC , VID: V01 , SN: SNI1353C80X

NAME: "C3900 AC Power Supply 2", DESCR: "C3900 AC Power Supply 2"
PID: PWR-3900-AC , VID: V01 , SN: SNI1353C816

=~=~=~=~=~=~=~=~=~=~=~==~=~=~=~=~=~=~=~=~=~=~==~=~=~=~=~=~=~=~=~=~=~=

#################### Show run of voice gateway A ####################

sccp ccm group 1
associate ccm 1 priority 1
associate ccm 2 priority 2
associate ccm 3 priority 3
associate profile 1 register TRN5475d04fe580
associate profile 2 register LyncRouter1
keepalive retries 5
switchover method immediate
switchback method immediate
switchback interval 15
signaling dscp af31
!

dspfarm profile 1 transcode
codec g711ulaw
codec g729ar8
codec g729abr8
codec g729r8
maximum sessions 80
associate application SCCP

dspfarm profile 2 mtp
codec g711ulaw
maximum sessions hardware 15
associate application SCCP

#################### Show run of Voice Gateway B ####################

sccp ccm group 1

associate ccm 1 priority 1
associate ccm 2 priority 2
associate ccm 3 priority 3
associate profile 1 register TRN5475d04ff180
keepalive retries 5
switchover method immediate
switchback method immediate
switchback interval 15
signaling dscp af31

dspfarm profile 1 transcode
codec g711ulaw
codec g711alaw
codec g729ar8
codec g729abr8
codec g729r8
maximum sessions 30
associate application SCCP

no dspfarm configured for mtp on voice gateway B

I am not an expert in cisco voice so therefore will appreciate your help in this regard.

Thanks

Chris Deren · ‎04-22-2015

SIP calls normally do not require any DSPs, you may end up needing transcoders depending on your call flow/codecs being used, however most simple deployments do not require them. MTPs should be built on the GW as software MTPs so no hardware is wasted.

AA BB · ‎04-22-2015

Hi Chris,

Thank for reply. Can you elaborate little more to me, i really want to understand it in detail. I already know the point that for codec conversions DSP resources will be utilized. our call manager is supporting codecs G711 and G729 and hopefully the same codecs will be supported on new SIP channels. So Still I am not sure whether there would be codec conversion or not? Secondly will DTMF on new SIP channel not use the DSPs? And can you please also let me know when MTP is used and what is its purpose?

Following is further detail of our gateways:

voice service voip
allow-connections h323 to h323
allow-connections h323 to sip
allow-connections sip to h323
allow-connections sip to sip
no supplementary-service h225-notify cid-update
signaling forward unconditional
h323
emptycapability
h225 id-passthru
h245 passthru tcsnonstd-passthru
modem passthrough nse codec g711alaw maximum-sessions 1
sip
bind control source-interface GigabitEthernet0/0
bind media source-interface GigabitEthernet0/0
min-se 360
header-passing
no update-callerid
!

Regards,

Yasir

Chris Deren · ‎04-22-2015

Transcoders (use DSPs) are only needed for devices which do not support requested codec. All cisco phones for example can negotiate most codecs natively, hence do not require transcoders. However let's say you have CCX application which is installed using either G711 or G729 codec and calls from carrier arrive with different codec then CCX CTI ports will engage transcoder. If all you have is SIP ISP offering either G711 or G729 or both, going to Cisco phones you should never need transcoders. MTPs may be engaged if let's the the DTMF method is mismatched between ISP/GW/CUCM, both for those you should use software IOS MTPs, though keep in mind that transcoders can also be used as MTPs, so it's always good idea to move transcoders into separate MRG below MTP MRG not to engage them when needing only MTP.