Technical data

DATA CENTER and CAMPUS NETWORKS DEPLOYMENT GUIDE
Deploying Brocade Networks with Microsoft Lync Server 2010 14 of 52
Figure 4. Lync reference architecture for campus environments.
Core Layer
The core layer consists of high-speed, high-performance, and highly available switches, which connect the
aggregation layers and, in smaller environments, the access layer. In many cases, redundant 10 GbE links connect
the different layers to provide the required bandwidth. The core layer is also known as the backbone; it is the Layer 3
domain that requires the maximum throughput, non-blocking, high density, low latency, and highly available design
architecture. That data center core is the source of packets forwarded to external entities, such as the WAN and
campus networks.
The core is one of the most important layers to consider in network design. If the core becomes a bottleneck, then all
attached devices behind it will be affected as they try to reach external devices. As network traffic starts to
proliferate, having robust equipment with adequate bandwidth in the core to meet network traffic demand is of the
utmost importance. Typically, in this layer QoS, BGP, OSPF, and other Layer 3 features are deployed.
Aggregation Layer
The aggregation layer aggregates multiple access layer switches and connects them to the campus or data center
core. Typically, devices such as firewalls and load balancers are located in the data center. In addition to the Layer 3
components listed above, this layer also deals with complex security, ACLs, scalability, QoS, STP, and so on. Typically,
each access and core switch is dual-connected to this layer for redundancy. In most cases, Layer 3 is connected to
the core, and Layer 2 is connected to the access layer.
Access Layer
The access layer is the connection point for notebooks, workstations, VoIP phones, WLAN access points, and servers
to “access” network services. The access layer is sometimes called the data center access layer or campus access
layer, but both provide the same functionality, that is, connecting devices to the network. Typically, the campus