AudioCodes Mediant 500 MSBR, User Manual

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User's Manual 322 Document #: LTRT-10375
Mediant 500 MSBR
tenant/customer on the other. For example, it would be a waste to allocate a capacity of
100 concurrent sessions to a small tenant for which 10 concurrent sessions suffice.
In a multi-tenant deployment, each tenant is represented by a dedicated SRD. The different
Layer-3 networks (e.g., LAN IP-PBX users, WAN SIP Trunk, and WAN far-end users) of
the tenant are represented by SIP Interfaces, which are all associated with the tenant's
SRD. As related configuration entities (SIP Interfaces, IP Groups, Proxy Sets,
Classification rules, and IP-to-IP Routing rules) are associated with the specific SRD, each
SRD has its own logically separated configuration tables (although configured in the same
tables). Therefore, full logical separation (on the SIP application layer) between tenants is
achieved by SRD.
To create a multi-tenant configuration topology that is as non-bleeding as possible, you can
configure an SRD (tenant) as
Isolated and Shared :

Isolated SRD: An Isolated SRD has its own dedicated SIP resources (SIP Interfaces,
Proxy Sets, and IP Groups). No other SRD can use the SIP resources of an Isolated
SRD. Thus, call traffic of an Isolated SRD is kept separate from other SRDs (tenants),
preventing any risk of traffic "leakage" with other SRDs.
Isolated SRDs are more relevant when each tenant needs its own separate
(dedicated) routing "table" for non-bleeding topology. Separate routing tables are
implemented using Routing Policies. In such a non-bleeding topology, routing between
Isolated SRDs is not possible. This enables accurate and precise routing per SRD,
eliminating any possibility of erroneous call routing between SRDs, restricting routing
to each tenant's (SRD's) sphere. Configuring only one Routing Policy that is shared
between Isolated SRDs is not best practice for non-bleeding environments, since it
allows routing between these SRDs.

Shared SRD: Isolated SRDs have their own dedicated SIP resources (SIP Interfaces,
Proxy Sets, and IP Groups). This may not be possible in some deployments. For
example, in deployments where all tenants use the same SIP Trunking service, or use
the same SIP Interface due to limited SIP interface resources (e.g., multiple IP
addresses cannot be allocated and SIP port 5060 must be used). In contrast to
Isolated SRDs, a Shared SRD can share its' SIP resources with all other SRDs
(Shared and Isolated). This is typically required when tenants need to use common
resources. In the SIP Trunk example, the SIP Trunk would be associated with a
Shared SRD, enabling all tenants to route calls with the SIP Trunk.
Another configuration entity that can be used for multi-tenant deployments is the Routing
Policy. Routing Policies allow each SRD (or tenant) to have its own routing rules,
manipulation rules, Least Cost Routing (LCR) rules, and/or LDAP-based routing
configuration. However, not all multi-tenant deployments need multiple Routing Policies
and typically, their configuration is not required. Isolated SRDs are more relevant only
when each tenant requires its own dedicated Routing Policy to create separate, dedicated
routing "tables"; for all other scenarios, SRDs can be Shared. For more information on
Routing Policies, see Configuring SBC Routing Policy Rules on page 692.
The figure below illustrates a multi-tenant architecture with Isolated SRD tenants ("A" and
"B") and a Shared SRD tenant ("Data Center") serving as a SIP Trunk: