Cisco Unified Communications 500 Series for Small Business (UC500)
The Cisco UC Series platforms can either be configured through the “Cisco Configuration Assistant” or via the IOS CLI. We have provided both examples below. The CCA is much easier to navigate for telephone configuration than feeling your way through the CLI. The configuration lines at the end of this page are the outputs from the CCA’s generated config.
Configuring the UC though the Cisco Configuration Assistant
Below is the SIP Trunking configuration screen for the UC. In this example we are using a SIP trunking service from an ITSP (Internet Telephony Service Provider) RBS (Rogers Business Solutions). RBS recommends using DNS SRV based dialing wherever possible. RBS had provided us with the DNS name of “sbc.myrbs.ca” to send and receive calls from (this was entered into the Proxy Server field). RBS also provided us with their DNS servers to simplify our configuration. These IPs were “126.96.36.199″ and “188.8.131.52″ (entered into DNS Server Address).
The Advanced Options screen provides some timer settings, which we have left mostly default. The only time we would expect to change any of these timers is when extremely long call duration is expected (such as a call duration of more than 12 hours). In some cases depending on the distance (latency) to the RBS SBCs the Invite Retries and Connection Timer should be at least doubled (to 4-5 retries & 400-500ms connect).
The Service Provider Settings tab provides some fine tuning of the SIP negotiation settings between the UC and ITSP. In this case we have given the ITSP a friendly name “ROGSIP” (to keep things short). We only ever want to use G711ulaw as our Preferred Audio Codec to eliminate the possibility of having a trans-coded audio stream. RBS recommends that we only ever use T.38 for faxing. Though they had mentioned G711 faxing is possible it not guaranteed, though T.38 faxing is guaranteed. RBS recommended using RFC2833 for DTMF with an RTP payload value of 101. These trunks are configured for direct IP-to-IP calling, therefore no registration is necessary.
Some important Voice configuration lines
Below is a copy of the “sanitized” configuration output from the Cisco Configuration Assistant as shown above. Carrier specific details have been removed.
Voice Codec Class Configuration
! voice class codec 1 codec preference 1 g711ulaw !
! dial-peer voice 1000 voip permission term description ** Incoming call from SIP trunk (CARRIER) ** session protocol sipv2 session target sip-server incoming called-number .% voice-class codec 1 voice-class sip dtmf-relay force rtp-nte dtmf-relay rtp-nte fax rate 14400 fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback pass-through g711ulaw ip qos dscp cs5 media ip qos dscp cs4 signaling no vad !
! dial-peer voice 1022 voip corlist outgoing call-national description **CCA*North American-10-Digit*Long Distance** translation-profile outgoing PSTN_Outgoing preference 1 destination-pattern 91[2-9]..[2-9]...... session protocol sipv2 session target sip-server voice-class codec 1 voice-class sip dtmf-relay force rtp-nte dtmf-relay rtp-nte fax rate 14400 fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback pass-through g711ulaw ip qos dscp cs5 media ip qos dscp cs4 signaling no vad ! dial-peer voice 1023 voip corlist outgoing call-local description **CCA*North American-10-Digit*10-Digit Local** translation-profile outgoing PSTN_Outgoing preference 1 destination-pattern 9[2-9]..[2-9]...... session protocol sipv2 session target sip-server voice-class codec 1 voice-class sip dtmf-relay force rtp-nte dtmf-relay rtp-nte fax rate 14400 fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback pass-through g711ulaw ip qos dscp cs5 media ip qos dscp cs4 signaling no vad !
SIP User Agent
! sip-ua keepalive target dns:sip.carrier.domain.name retry invite 2 retry register 10 timers connect 100 timers keepalive active 100 sip-server dns:sip.carrier.domain.name host-registrar !
Configuration “dns:sip.carrier.domain.name” is for DNS SRV-Based dialing
This can also be IP-Based using “ipv4:xxx.xxx.xxx.xxx”
Some basic network level configuration lines
! interface FastEthernet0/0= description ROUTER OUTSIDE (WAN) FACING INTERFACE ip address dhcp ip nat outside ip virtual-reassembly in ! interface Integrated-Service-Engine0/0 description INTERFACE TO INTEGRATED CUE SERVER ip unnumbered Loopback0 ip nat inside ip virtual-reassembly in service-module ip address 10.1.10.1 255.255.255.252 service-module ip default-gateway 10.1.10.2 ! interface FastEthernet0/1/0 description SWITCHPORT INSIDE switchport voice vlan 100 macro description cisco-phone spanning-tree portfast ! interface FastEthernet0/1/8 description SWITCHPORT SIP TRUNKING switchport access vlan 101 ! interface Vlan1 description ROUTER INSIDE (DATA) VLAN ip address 192.168.10.1 255.255.255.0 ip access-group 102 in ip nat inside ip virtual-reassembly in ! interface Vlan100 description ROUTER INSIDE (VOICE) VLAN ip address 10.1.1.1 255.255.255.0 ip access-group 103 in ip nat inside ip virtual-reassembly in ! interface Vlan101 description ROUTER SIP TRUNKING (EXPANSION) FACING INTERFACE ip address 10.41.255.10 255.255.255.248 ip nat inside ip virtual-reassembly in !