Figure 2b shows the addition of two separate IP telephony workgroups 1 and 2. The solid
black line shows that intra-module IP telephony traffic still gets switched independently on the
connectivity module. The dashed purple line shows inter-module (workgroup #1 to workgroup
#2) IP telephony traffic traverses the high-speed 36.6 Gbps inter-modular central switching
fabric. If there is extremely heavy inter-module traffic, it may be desirable to use Class of
Service (CoS) features to prioritize traffic using the IEEE802.1p standard. Many VoIP solutions
such as the Mitel support IEEE 802.1p and set the priority bits for Quality of Service (QoS) so
there is no need for the 4108gl to set the 802.1p tag. It merely needs to recognize it and
prioritize it accordingly. Also, since a standard voice conversation requires less than one
tenth of a percent of a 100Mbps link, bandwidth reservation is not a concern when using a
4108gl. This can be compared to the need for a carpool lane on an un-crowded freeway –
there is no need for the carpool lane!
Note that the intra-workgroup traffic described in Figures 1a and 1b above, is still switched
independently of the additional traffic loads offered by the IP telephony scenarios shown in
Figures 2a and 2b.
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