Microsoft LynServer 2013 : Dependent Services and SQL - Network Dependencies (part 2) - Defining Network Sites

Segregation of Traffic

To ensure the best experience for users, it is highly recommended that administrators separate VoIP traffic from other network traffic by placing voice devices on a VLAN that is dedicated to voice functions. Also, users with USB-based devices should connect to a wired network rather than a wireless network whenever possible. Using a segregated VLAN for phone devices makes it much easier to leverage important network features such as Quality of Service (QoS) to ensure the best possible voice quality for end users. This configuration also serves to simplify monitoring, because endpoint devices are logically grouped at the network level.

Ethernet Switch Considerations

All Lync Phone Edition devices have two important features that have an impact on the choice of Ethernet switch: LLDP-MED and PoE (Power over Ethernet). To leverage these features, the connected Ethernet switch ports must support these same features. Specifically, LLDP-MED requires support for the IEEE802.1AB and ANSI/TIA-1057 standards. To utilize PoE, the switch ports must support one of two PoE standards, either 802.3AF or 802.3at.

The configuration of LLDP-MED is specific to the Ethernet switch model. Often, this feature needs to be enabled globally within the switch, and typically the voice VLAN must be specified for use with LLDP-MED within the switch configuration.

Defining Network Sites

Lync Server sites are used to organize resources according to geography and bandwidth. IP subnets are then associated with the sites so that the Lync Servers can identify the locations where endpoints are located. A correctly configured Lync site topology allows Front End Servers to determine how call setup and routing should be handled; therefore, this is an important aspect of the Lync configuration. All subnets in a network should be defined and associated with a Lync site. Although this can be configured using the Lync Server Control Panel, in an enterprise network it could take a considerable amount of time to input all IP subnets into the configuration. For larger networks, this task is more easily handled using a simple comma-separated value (CSV) file and the Lync Management Shell. For example, a CSV file can be created including separate fields for network address, subnet mask bits, description, and Lync site ID, as shown here:

IPAddress, mask, description, NetworkSiteID
10.0.0.0, 24, "NA:SF subnet", SF
10.1.0.0, 24, "EMEA:Dublin subnet", Dublin
10.2.0.0, 24, "EMEA:London subnet", London

Using a sample CSV filename of subnet.csv, these values can then be easily imported into the Lync Server network configuration by using the Lync Management Shell to execute the following command:

import-csv subnet.csv | foreach {New-CSNCSSubnet $_.IPAddress -MaskBits $_.mask -Description $_.description -NetworkSiteID $_.NetworkSiteID}

This command can then be scheduled to run regularly as a script, such that whenever new sites or subnets are added to the network, the CSV file is adjusted to reflect these and the script maintains the most current network topology.