Specifications

25 Reference Architecture | Dell
TM
Unified Communication Solution with Microsoft® Lync® Server 2013 for Single Site
Implementation | Version 1.0
3.4.1 Sonus SBC 1000/2000
The Sonus SBC 1000/2000 is a Microsoft-qualified enhanced media gateway that has a session border
controller (SBC) for SIP trunking and gateway operation for T1/E1 telecom connectivity.
The SBC 1000 offers two 1GbE ports for SIP trunking and two T1/E1 interfaces while SBC 2000 offers four
1GbE ports for SIP trunking and sixteen T1/E1 interfaces. When used as a gateway, the SBC 1000/2000 can
function between the legacy PBX infrastructure within the data center and the Lync Mediation Server. In
this particular case, the Mediation Servers are collocated on the Front End and hence the Front End pool is
the next hop for the SBC 1000/2000 gateway. If used as an SBC, this device needs to be equipped with SIP
trunks from an Internet telecom service provider (ITSP) and connects through the provider’s switching
network into the PSTN. Both cases enable calls to external phone users.
Figure 7 shows the connectivity options for SBC 1000/2000, whereby the device can act as both an
enhanced media gateway connecting to a PSTN via T1/E1 interfaces or as an SBC connecting to an ITSP
via a SIP trunk. The Lync environment is in turn connected via SIP TCP or TLS. This provides an option to
fallback to a PSTN in the event the connectivity to the ITSP goes down. Further, the SBC 1000/2000 can
be configured in a highly available active-active mode, which provides resiliency and scalability by load
balancing the traffic.
Figure 7 Sonus SBC connectivity options
The SBC 2000 is similar to the SBC 1000 with more expandability options and the ability to scale to a
higher number of simultaneous sessions. Thus, depending on an organization’s voice needs, the
appropriate voice gateway should be considered. This reference architecture leverages Sonus SBC 1000.
The Sonus SBC series also supports the Lync Survivable Branch Appliance (SBA). Using the SBA, the branch
office communications are always available, even when the WAN link to the central site is down.
3.4.2 SBC 1000 Gateway Configuration
In order to configure the SBC 1000 as a gateway or SBC, the following configurations must be made:
• Signaling Groups: A signaling group defines a virtual trunk that receives inbound calls and sends
outbound calls. For example, a signaling group can comprise a trunk to Lync endpoints. This signaling
group would be set to point to the Mediation Server as its next hop. The Figure 8 screenshot shows an
example of such a signaling group.
ITSP
PSTN
LAN
SIP-TRUNK
T1/E1 to PSTN
SIP TCP/TLS
SIP TCP/TLS
Sonus SBC 1000/2000
Sonus SBC 1000/2000
Lync
Environment
SB
C
20
00
A
d
m
i
n
2 3 41
6 7 85
SB
C
20
00
A
d
m
i
n
2 3 41
6 7 85
SIP