Cisco default dial-peer codec

This default dial peer is referred to as dial-peer 0 or pid Note: There is an exception to this statement. Cisco voice and dial platforms, such as the AS53xx and AS, require that a configured inbound dial peer is matched for incoming POTS calls to be accepted as voice calls. If there is no inbound dial peer match, the call is treated and processed as a dial-up modem call.

Dial-peer 0 pid:0 has a default configuration that cannot be changed. The default dial-peer 0 fails to negotiate non-default capabilities, services, and applications such as:. The default dial peer does not mark packets to DSCP 0.

All voice packets on the routers are marked by default this can be overridden by the dial peer , signaling with AF31 and media with EF.

Calls that match the default dial peer 0 should also have this behavior. There are implications for inbound dial peer matching when the isdn overlap-receving command is configured on ISDN interfaces.

After every digit is received at the ISDN layer, dial peers are checked for matches. If a full match is made, the call is routed immediately to the session app in this case without waiting for additional digits. The ' T ' terminator can be used to suspend this digit-by-digit matching and force the router or gateway to wait until all digits are received. Now, assume that an incoming call arrives with no calling number information and is matched with the POTS dial peer based on the destination-pattern 9T command.

In order to not replace the empty calling number field, create a dummy POTS dial peer with just the incoming called-number command configured. Because the incoming called-number statement has higher priority than destination pattern for inbound POTS matching, dial-peer voice 2 becomes the POTS dial peer used.

The Warning message shown here, which displays when dial-peer is configured with incoming called-number T, might raise questions in regards to the dial-peer selection with an empty called number from an actual router. Therefore, a match based on a "null" called number will occur ONLY if there is no match based on either answer-address or port-number.

In case of overlap dialing, a "null" called number will not match "incoming called-number T" because timeout has not occurred. A "null" called-number will match "incoming called-number T" only in case of ENBLOCK and there is no match either because of answer-address and port-number.

The warning you see when you configure "incoming called-number T" refers to this specific case. On DID calls, also referred to as one-stage dialing, the setup message contains all the digits necessary to route the call, and the router or gateway should not do subsequent digit collection. When the router or gateway searches for an outbound dial peer, the device uses the entire incoming dial string. This matching is variable-length by default.

This match is not done digit-by-digit because by DID definition, all digits have been received. Assume the DID dial-string is "". In this case, the router matches dial peer 4 and forwards the complete dial-string "". This case is also referred to as two-stage dialing. If DID is not configured on the matched incoming dial peer, the router or gateway enters the digit collection mode digits are collected inband.

Outbound dial peer matching is done on a digit-by-digit basis. The router or gateway checks for dial peer matches after the device has received each digit and then routes the call when a full match is made.

These examples help clarify this concept:. Assume the dial-string is "". Immediately after the router receives the digit "6", the router matches dial peer 3 and routes the call forwarding only the digits "".

In this case, the longest-prefix rule applies, and dial peer 4 is matched for the outbound call leg. There are situations where expected dial-strings do not have a set number of digits. PDF - Complete Book Updated: January 6, Chapter: Voice Packetization. Voice Packetization After the voice wavelength is digitized, the DSP collects the digitized data for an amount of time until there is enough data to fill the payload of a single packet. Table 1. Enter your password if prompted.

Step 3 dial-peer voice number voip Example: Device config dial-peer voice 1 voip Enters dial peer configuration mode for the specified VoIP dial peer. Step 4 codec codec-name bytes voice-payload-size [ fixed-bytes ] Example: Device config-dial-peer codec gr8 bytes 30 fixed-byte Configures a different packetizations for a voice codec.

Was this Document Helpful? Yes No Feedback. VAD parameters can be tuned on an individual dial peer basis, but it is normally best to turn off the mechanism. Most environments are connecting their voice gateway routers to the network via Fast Ethernet Mbps or Gigabit Ethernet Mbps technology where there is little to no need for the bandwidth savings of G.

The codec default was change to G. The global configuration below would be used to set up the voice-class codec: Voice class codec 1 Codec preference 1 gulaw Codec preference 2 gr8 Each VoIP dial-peer can now leverage the global codec voice class as shown below: Dial-peer voice voip Voice-class codec 1 The session target command is used in VoIP dial-peers to point the dial-peer to an IP address, while POTS dial-peers used the port command to steer calls to a TDM interface on the router.

The next blog will discuss the preference command used with dial-peer hunting and continue our conversation of VoIP dial-peers. Here are the latest Insider stories. More Insider Sign Out.