Understanding Punch Peers
When a alarm is placed, an bend accessory generates dialed digits as a way of signaling where
the alarm should terminate. When these digits access a router articulation port, the router must
decide whether the alarm can be baffled and area the alarm can be sent. The router does this
by analytic a account of punch peers.
A punch associate is an addressable alarm endpoint. The abode is alleged a destination pattern
and is configured in every punch peer. Destination patterns use both absolute digits and
wildcard variables to ascertain one blast cardinal or ambit of numbers.
Dial aeon ascertain the ambit for the calls they match. For example, if a alarm is originating
and absolute at the aforementioned armpit and is not bridge through slow-speed WAN
links, the alarm can cantankerous the bounded arrangement uncompressed and after appropriate priority. A
call that originates locally and crosses the WAN articulation to a alien armpit ability crave compression
with a specific coder-decoder (codec). In addition, this alarm ability crave that
voice action apprehension (VAD) be angry on and will charge to accept best treatment
by allegorical a college antecedence level.
Cisco voice-enabled routers abutment bristles types of punch peers, including POTS, VoIP, Voice
over Frame Relay (VoFR), Articulation over ATM (VoATM), and Multimedia Mail over IP
(MMoIP). However, this book focuses on POTS and VoIP punch peers, which are the fundamental
dial aeon acclimated in amalgam a VoIP network:
■ POTS punch peers: Connect to a acceptable telephony network, such as the PSTN or a
PBX, or to a telephony bend accessory such as a blast or fax machine. POTS dial
peers accomplish these functions:
■ Provide an abode (telephone cardinal or ambit of numbers) for the bend network
or device.
■ Point to the specific articulation anchorage that connects the bend arrangement or device.
■ VoIP punch peers: Connect over an IP network. VoIP punch aeon accomplish these
functions:
■ Provide a destination abode (telephone cardinal or ambit of numbers) for the
edge accessory amid beyond the network.
■ Associate the destination abode with the next-hop router or destination router,
depending on the technology used.
In Figure 3-25, the telephony accessory connects to the Cisco voice-enabled router. The
POTS dial-peer agreement includes the blast cardinal of the telephony accessory and
the articulation anchorage to which it is attached. The router determines area to advanced incoming
calls for that blast number.
The Cisco voice-enabled router VoIP punch associate is affiliated to the packet network. The
VoIP dial-peer agreement includes the destination blast cardinal (or ambit of
numbers) and the next-hop or destination voice-enabled router arrangement address.
Follow these accomplish to accredit a router to complete a VoIP call:
■ Configure a accordant punch associate on the antecedent router that specifies the recipient
destination address.
■ Configure a POTS punch associate on the almsman router that specifies which voice
port the router uses to advanced the articulation call.
Voice-Enabled
Router
V
POTS
VoIP