Technical data

DATA CENTER and CAMPUS NETWORKS DEPLOYMENT GUIDE
Deploying Brocade Networks with Microsoft Lync Server 2010 37 of 52
Hardware Requirements
• Campus and Data Center Core Switches – Brocade MLX
• Campus Aggregation Switches – Brocade SX 800
• Campus / Branch Access Switch – Brocade ICX
• Data Center Ethernet Fabric – Brocade VDX
• Data Center Storage Fabric – Brocade 5120
• Data Center Hardware Load Balancer – Brocade ServerIron ADX 1000
• Servers: HP DL-380 with 4 GB RAM, 146 GB hard drive, Windows 2008 64 bit
Test Approach
When a call is assigned a MOS score greater than 3.5, based on the Microsoft Quality of Experience monitoring role,
specifically the Listening Quality (LQ) MOS scale, it is considered a successful call.
Table 6. Listening Quality MOS scale
MOS Score
Quality of Speech
5
Excellent
4
Good
3
Fair
2
Poor
1
Bad
The test consisted of the three branch offices with a varying latency and different amounts of packet loss. To
simulate the latency and packet loss, a Shunra WAN simulator was used. To simulate I/O, Iometer software (from the
Open Source Development Lab [OSDL]) was used on the client side to saturate the link.
On the client side, both Microsoft Qualified soft clients (headsets) and Polycom CX600 IP phones optimized for
Microsoft Office Communicator 2010 were used to place the calls. The Polycom CX 600 provides a high-quality
handset for crystal-clear, natural conversations without echoes or feedback, all at a very low cost.
Microsoft Lync Server 2010 Monitoring Server was used to provide the key metrics that measured the success of the
tests. These metrics included average jitter, average delay, average packet loss, and average MOS score, as
summarized in Table 7. Anything with a MOS score of less than 3.5 was not acceptable. Note that a score of 4 or
above is considered “toll quality,” and most of the scores in this testing were toll quality. In addition to the results
provided by the Monitoring Server, subjective evaluation was also used to judge the sound quality and the voice
quality. When the tests were conducted, the quality of all calls was considered clear with no feedback, echoes or
long pauses. In addition, the quality of the call for both voice and video were better than Microsoft Communication
Server 2010, especially under extreme conditions.