VoIPTechBlogs

With Cisco IOS gateways, dial-peers are used to match phone numbers, and the destination can be a SIP Proxy Server, DNS SRV, or IP address. The following example shows a Cisco IOS gateway configuration to send calls to a SIP Proxy Server using the SIP Proxy’s IP address.

sip-ua
sip-server ipv4:10.4.1.100:5060
dial-peer voice 1000 voip
session target sip-server
… Read the rest of this entry »

MOH is an audio stream which can be played to PSTN and VoIP G.711 or G.729 callers who are placed on hold by phones in a Cisco Unified CME system. This audio stream is intended to reassure callers that they are still connected to their calls.

When the phone receiving MOH is part of a system that uses a G.729 codec, transcoding is required between G.711 and G.729. The G.711 MOH must be translated to G.729.

Note: Because of compression, MOH using G.729 is of significantly lower fidelity than MOH using G.711.

Below are some MOH resources

• Flash Memory: MOH can be played from local stored files in flash memory without the requirement of external source Read the rest of this entry »

This feature is very useful on multi-line IP phones where lifting the handset automatically selects the first ringing line on the phone or, if no line is ringing, selects the first available idle line for outgoing calls. This is the default behavior for all multi-line IP phones. But in some situations you require that a specific line button should be explicitly pressed to select an outgoing line or to answer an incoming call. In Cisco CME 3.0 and later, you have the flexibility to assign the type of line selection that each IP phone uses.

The Automatic Line Selection feature allows you to specify, on a per-phone basis, the line that is selected when you pick up a phone handset. Any of the following behaviors can be assigned on a per-phone basis:

• Automatic line selection Picking up the handset answers the first ringing line or, if no line is ringing, selects the first idle line. Use the auto-line command with no keyword or argument. This is the default. Read the rest of this entry »

• After hours call blocking blocks specific number for a specific time period
• Configured from telephony service mode
• Phones can be exampled (always or through pins)
• 24-7 block patterns can never be allowed

After-hours call blocking has three major steps of configuration:

1. Define days and/or hours of the day that your company considers off-hours.
2. Specify patterns that you would like to block during the times specified in Step 1.
3. Create exemptions to the policy, if needed. Read the rest of this entry »

• Paging is a one-way, speakerphone based announcement
• Accomplished by creating a paging number and assigning phones to the paging number
• Each IP phone can only be assigned one paging number
• Supports unicast (mean each phone will receive its own audio stream) or multicast (all phones will listen to same single audio stream)
• Support multiple paging groups which enables you to assign one phone to more than one paging group

CME(config)#ephone-dn 80
CME(config-ephone-dn)#number 5555
CME(config-ephone-dn)#paging
CME(config-ephone-dn)#exit
CME(config)#ephone 1 Read the rest of this entry »