Cisco Cisco IPCC Web Option Design Guide
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Cisco Unified Contact Center Enterprise 7.0, 7.1, and 7.2 SRND
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Chapter 2 Deployment Models
IPT: Clustering Over the WAN
Unified CM node to which the agent phones are registered. This failover situation should only be
temporary, and the link must be restored as fast as possible so that the public and private
Unified ICM traffic are carried over separate links. If the redundant link that carries the Unified ICM
private traffic also fails, Unified ICM instability and data loss can occur, including the corruption of
one Logger database, and manual intervention could be required. That is why it is very important to
actively monitor any network failure at all times.
temporary, and the link must be restored as fast as possible so that the public and private
Unified ICM traffic are carried over separate links. If the redundant link that carries the Unified ICM
private traffic also fails, Unified ICM instability and data loss can occur, including the corruption of
one Logger database, and manual intervention could be required. That is why it is very important to
actively monitor any network failure at all times.
The links must also be sized correctly in order to accommodate this failover situation where the
private link carries the entire WAN traffic, including the public and ICCS traffic. QoS and bandwidth
must be configured according to the guidelines in the chapter on
private link carries the entire WAN traffic, including the public and ICCS traffic. QoS and bandwidth
must be configured according to the guidelines in the chapter on
.
Figure 2-11
Network Architecture After Failure of the Unified ICM Public Network
•
It is also possible to allow the private link to fail-over to the public link. However, if the total failover
latency takes more than 500 ms (five times the TCP keepalive interval of 100 ms), the Unified CCE
system considers the private link to be down. If the public link is also down, Unified ICM instability
and data loss can occur, including the corruption of one Logger database, and manual intervention
could be required. The total failover latency typically includes the round-trip transmission latency,
the routing protocol convergence delay, the HSRP convergence delay if applicable, queuing and
packetization delays, and any other delay that would be applicable. If the total failover latency is
higher than 500 ms, or if you suspect possible recurrent network flapping, Cisco strongly
recommends deploying three WAN links and keeping the private traffic separate from the public
traffic at all times. Also, the links must be sized correctly in order to accommodate this failover
situation where the public link carries the entire WAN traffic, including the private and ICCS traffic.
Again, this failover situation should only be temporary, and the link must be restored as fast as
possible so that the public and private Unified ICM traffic are carried over separate links.
latency takes more than 500 ms (five times the TCP keepalive interval of 100 ms), the Unified CCE
system considers the private link to be down. If the public link is also down, Unified ICM instability
and data loss can occur, including the corruption of one Logger database, and manual intervention
could be required. The total failover latency typically includes the round-trip transmission latency,
the routing protocol convergence delay, the HSRP convergence delay if applicable, queuing and
packetization delays, and any other delay that would be applicable. If the total failover latency is
higher than 500 ms, or if you suspect possible recurrent network flapping, Cisco strongly
recommends deploying three WAN links and keeping the private traffic separate from the public
traffic at all times. Also, the links must be sized correctly in order to accommodate this failover
situation where the public link carries the entire WAN traffic, including the private and ICCS traffic.
Again, this failover situation should only be temporary, and the link must be restored as fast as
possible so that the public and private Unified ICM traffic are carried over separate links.
•
If QoS and bandwidth are configured correctly (see the guidelines in the chapter on
, for more details), these WAN links can be
converged with other corporate traffic.
•
With a SONET fiber ring, which is highly resilient and has built-in redundancy, the public and
private traffic can be carried over the same SONET ring under normal operations or following a
network failover. A separate link for the private traffic is not required in this case. Also, two routers
are required on each side of the WAN for redundancy. Under normal operations, one router should
be used for the Unified ICM public traffic and the other router should be used for the Unified ICM
private traffic. (See
private traffic can be carried over the same SONET ring under normal operations or following a
network failover. A separate link for the private traffic is not required in this case. Also, two routers
are required on each side of the WAN for redundancy. Under normal operations, one router should
be used for the Unified ICM public traffic and the other router should be used for the Unified ICM
private traffic. (See
.) The other rules described in this section also apply.
ICM public + ICM private
+ ICCS
ICM public + ICM private
+ ICCS
WAN
WAN
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