Cisco Unified Bound Elements
Figure 5-6 shows sample adjustment of Cisco UBEs in a account provider’s network.
Chapter 5: Examining VoIP Gateways and Aperture Ascendancy Protocols 255
DGK Via GK
Private Network
10.10.x.x
10.10.10.5
12.10.10.11
Cisco UBE
12.10.10.10
Public Network
12.10.x.x
PSTN
12.10.10.12
U U
DGK
Private Network
192.168.x.x
192.168.10.5
Figure 5-6 Cisco Unified Bound Element
A Cisco UBE is an alternative H.323 component. The Cisco UBE facilitates accessible and costeffective
connectivity amid absolute VoIP account provider networks. Some in the
industry accredit to Cisco UBEs as “session bound controllers.” The Cisco UBE provides a
network-to-network interface point for billing, security, Cisco Unified Communications
Manager interconnectivity, Alarm Admission Ascendancy (CAC), and signaling interworking. It
performs best of the aforementioned functions of a PSTN-to-IP gateway, but joins two VoIP call
legs. Media packets can either breeze through the aperture and adumbrate the networks from
each other, or breeze about the Cisco UBE if arrangement aegis is not of primary
importance.
Figure 5-6 illustrates a basal Cisco UBE network. From the angle of the private, or
customer, networks, the Cisco UBE will arise as a distinct accessible abode that charge be
routable on their clandestine networks (in this case, a 12.x.x.x abode routable on the
10.10.x.x and 192.168.x.x networks). Care charge be taken at the Cisco UBE to ensure
proper acquisition restrictions are in abode to anticipate advice anon amid the
private networks absorbed to it. Additionally agenda that this archetypal works alone if no overlapping
address schemes are acclimated on the chump networks. Finally, to the hop-off gateways on
the accessible network, all calls will arise to arise from the 12.x.x.x abode of the
Cisco UBE and not the clandestine addresses on the chump networks. Additionally agenda that the
gatekeepers apparent in Figure 5.6 ascendancy anniversary area independently, with the 12.10.10.11
gatekeeper acting as the ascendancy point for the accessible network, and accordingly the Cisco
UBE.
Codec-order canning enables a aperture to canyon codec preferences to the terminating
leg of a VoIP call. This affection was developed primarily for Cisco UBEs, which are configured
to use a cellophane codec. The cellophane codec enables a Cisco UBE to pass
codecs from the basic endpoint to the absolute endpoint. However, antecedent versions
of the Cisco UBE did not bottle the best adjustment of the codecs.
With codec-order preservation, the Cisco UBE passes codecs clearly from the
originating device, listed in adjustment of preference, to the absolute device. It additionally enables
gateways to canyon user-configured codecs in their adopted adjustment back the endpoints
exchange capabilities, enabling endpoints to use the codec that best apparel both devices.