In the sections that follow, there are examples of the components and hardware requirements for different sizes of call recording solutions.

However, critical factors related to network and I/O conditions are examined first.

IOPS

A very important parameter in Genesys Quality Management Suite storage performance is Input/Output Operations Per Second (IOPS).

Recording is the most demanding operation for storage systems in Genesys Quality Management Suite. Recording storage should always be independent from other storage if the IOPS limit is being approached.

Each call recording requires around 4 IOPS, so for 500 concurrent calls this is around 2000 IOPS.

The Decoder requires 3 I/O operations during operation, while a local database and Screen Capture add further I/O operations.

The Genesys Quality Management Suite database is very demanding on both storage and CPU capacity, particularly if Quality Manager is installed and is heavily used for evaluations. We recommend that for large installations, the database should be running on a separate server.

Typical IOPS values for current HDD drives are as follows - only fast SAS drives should be considered for call recording storage.

7,200 rpm SATA drives HDD ~75-100 IOPS SATA 3 Gb/s

10,000 rpm SATA drives HDD ~125-150 IOPS SATA 3 Gbit/s

10,000 rpm SAS drives HDD ~140 IOPS SAS

15,000 rpm SAS drives HDD ~175-210 IOPS SAS

Solid State Drives (SSD) offer much higher IOPS performance, so are an ideal candidate for the role as a call recording cache (short term storage, before calls are archived to permanent storage consisting of slower HDD drives).

Network Requirements

The following factors are critical in determining the response and quality of an IP-based call recording system:

  • Latency: Latency is a measure of time delay experienced in a system.
  • Jitter: Jitter is the variability over time of the packet latency across a network.
  • Bandwidth: Bandwidth is rate of data transfer, bit rate or throughput, measured in bits per second (bps).

Good network throughput in a multi-server environment is essential, particularly where the NFS (Network File System) is used. Network throughput is characterized by a combination of the bandwidth – usually 100 Mbit/sec or 1 Gbit/sec – and the latency. Higher jitter factors, where in the worst case packets are lost during transit, also negatively affect the throughput.

Resources shared between servers can also affect throughput, such as:

  • A decoder loading recorded calls over the network
  • SQL queries and result sets
  • Call data in transit to network storage

NFS Performance

NFS (Network File System) performance degradation is caused by the following:

  • Network connection speed much lower than the local disk connection (SAS has 3-6 Gbits / sec).
  • No caching (the file being loaded over the network could be modified any time by another process).
  • Network latency being much higher than local latency (all switches / routers on the way, and so on).
  • Network overhead being much higher than local transfer. The worst case is transferring a large number of small files.

Database Performance

Database performance is dependent on the distribution of CPU, RAM and storage:

  • Small database queries (SQL Selects) produce potentially huge results, that need to be transferred across the network.

Call Data

  • Calls that are delivered to recorders over the same network interface reduce the network bandwidth available for other network services.
  • There is always a tradeoff between sharing resources (CPU, RAM, storage) and limitations imposed by the network.

In summary, it is beneficial to ensure that a multi-server implementation shares resources and distributes load (to obtain more CPU horsepower, for example), but this is dependent on the servers being connected to a network that is fast enough to deliver data without allowing servers to enter an idle state, waiting for further tasks.

Acronyms for Call Recording Services

In the following hardware configurations, Call Recording services are referred to by the following acronyms:

  • RMI: Remote Method Invocation. The RMI is used to communicate between modules.
  • CONFIG: The Configuration Manager.
  • CORE: The central Call Recording control module.
  • RS: SPAN recorder.
  • SLR: Active recorder.
  • DECODER: decoder server.
  • CC IM: Contact Center Integration Module, for example, Genesys CIM.
  • TOOLS: Media Lifecycle Management tools, for example, the Archive utility.
  • WEB UI: Call Recording Web-based user/administration interface.
  • DATABASE: The main call information database.
  • RTS: Real-time protocol sniffer (for example, JTAPI, SIP, Skinny).

Recommendations for All Configurations

If a server with CentOS or RedHat 32 bit has more than 4 GB RAM, make sure that the Physical Address Extension (PAE) enabled kernel is installed.

If the storage system causes a bottleneck in Call Recording performance, especially during peak hours, use a fast SLC SSD as a write through cache where the recorded files are stored in addition to the slower permanent storage (based on HDD).

The size of the SSD cache should be at least as large as the amount of data recorded during the peak hours of one business day.

Record up to 50 Concurrent Calls - Call Recording Only

The recommended server hardware configuration for 50 concurrent calls is as follows:

Call Recording Only - 50 Calls

Running Services:RMI, CONFIG,CORE, RS/SLR, DECODER, CC IM, TOOLS, WEB UI, DATABASE, RTS

CPU

Dual core (Intel CORE2) processor 2.0Ghz or better

RAM

4 GB RAM minimum

HDD

2x Drives RAID 1, 7,200 rpm (approximately 200 IOPS required)

Network Cards2x 100 Mb Ethernet minimum for Passive recording 1x 100 Mb Ethernet minimum for Active recording
Storage Example
Average length of calls180 seconds
Average handle time270 seconds ( 90 seconds After Call Work)
Maximum concurrent calls50
Number of calls a day4800 for an 8 hour day
Percentage of calls recorded100%
Storage required for one month of mp3 media86 GB + 20GB for system
Storage required for 12 months of mp3 media1 TB +20 GB for system

 

Record up to 100 Concurrent Calls - Call Recording Only

The recommended server hardware configuration is as follows:

Call Recording Only - 100 Calls

Running Services:

RMI, CONFIG, CORE, RS/SLR, DECODER, CC IM, TOOLS, WEB UI, DATABASE, RTS

CPU

Quad core (Intel CORE2) 2.0Ghz or better

RAM

4 GB Minimum, 8 GB Recommended

HDD

4x 10,000 rpm Hard Drive, RAID 10 (approximately 400 IOPS required)

Network Cards2x 100 Mb Ethernet minimum for Passive recording 1x 100 Mb Ethernet minimum for Active recording
Storage Example
Average length of calls180 seconds ( 3 minutes)
Average handle time270 seconds
Maximum concurrent calls100
Number of calls a day9600 for an 8 hour day
Storage required for one month of mp3 media180 GB + 20GB for system
Storage required for 12 months of mp3 media2.2 TB + 20 GB for system

Record up to 100 Concurrent Calls - Call Recording and Quality Manager

This scenario assumes that there will be around 10 supervisors (one supervisor to every ten agents) accessing Quality Manager simultaneously. The recommended server hardware configuration is as follows:

 

Call Recording and Quality Manager - 100 Calls

Running Services:RMI, CONFIG,CORE, RS/SLR, DECODER, CC IM, TOOLS, WEB UI, DATABASE, RTS

CPU

Intel Quad Core 55XX 2.0Ghz or better (4 Cores)

RAM

16 GB RAM

HDD

4x RAID 10, 10,000 rpm Hard Drive

Network Cards2x 100 Mb Ethernet minimum for Passive recording 1x 100 Mb Ethernet minimum for Active recording
Storage Example
Average length of calls180 (3 min)
Average handle time270 seconds (4.5 minutes)
Maximum concurrent calls100
Number of calls a day9600
Storage required for one month of mp3 media180 GB + 20GB for System
Storage required for 12 months of mp3 media2.2 TB + 20GB for System
Storage required for Quality Manager Database20 GB

 

Record up to 250 Concurrent Calls - Call Recording Only

The recommended server hardware configuration is as follows:

Call Recording Only - 250 Calls

Running Services:RMI, CONFIG,CORE, RS/SLR, RTS, DECODER, CC IM, TOOLS, WEB UI, DATABASE

CPU

Intel Quad Core 55XX 2.3 Ghz or better

RAM

8 GB Minimum

HDD

Two options for recording cache (approx 1000 IOPS required):

1. SSD having a total minimum 1,000 IOPS using 4 kB blocks

2. 4x SAS 10,000 rpm for RAID 10 partition with write cache enabled to decrease HDD IOPS

Dedicated HDD for permanent storage: 4 x 7200 rpm for RAID 10

Network Cards2x 1 Gigabit Ethernet
Storage Example
Average length of calls180 seconds
Average handle time270 seconds
Maximum concurrent calls250
Number of calls a day24,000 for an 8 hour day
Percentage of calls recorded100%
Storage required for one month of mp3 media450 GB + 20GB for system
Storage required for 12 months of mp3 media5.4 TB + 20GB for system

Record up to 250 Concurrent Calls - Call Recording and Quality Manager

This scenario assumes that there will be around 25 supervisors (one supervisor to every ten agents) accessing Quality Manager simultaneously. This solution requires two servers:

  • Server 1: Call Recording recording and decoding modules
  • Server 2: Quality Manager including database, MLM Tools and Call Recording Web GUI

The recommended server hardware configuration is as follows:

 

Server 1: Call Recording - 250 Calls

Running Services:RMI, CONFIG,CORE, RS/SLR, RTS, DECODER, CC IM

CPU

Intel Quad Core 55XX 2.3 Ghz or better

RAM

8 GB Minimum, 16 GB Recommended

HDD

Two options for recording cache (approx 1000 IOPS required for recording, additional IOPS produced by Quality Manager)

1.SSD having a total minimum 1,000 IOPS using 4 kB blocks

2. 4x SAS 10,000 rpm for RAID 10 partition with write cache enabled to decrease HDD IOPS

Additional HDD requirements are produced in relation to how heavily (and when - if off peak or during peak hours) Quality Manager is used.

If more concurrent users use Quality Manager, it is recommended to deploy the database on a separate HDD.

Dedicated HDD for permanent storage: 4 x 7,200 rpm for RAID 10

Network Cards2x 1 Gigabit Ethernet
Storage Example
Average length of calls180 seconds
Average handle time270 seconds
Maximum concurrent calls250
Number of calls a day24,000 for an 8 hour day
Percentage of calls recorded100%
Storage required for one month of mp3 media450 GB + 20GB for system
Storage required for 12 months of mp3 media5.4 TB + 20GB for system

 

Server 2: Quality Manager

Running Services:RMI, TOOLS, WEB UI, DATABASE

CPU

Intel Quad Core 55XX 2.0Ghz or better

RAM

16 GB RAM

HDD

Fast storage: 4 x 10,000 rpm for RAID 10

Storage required for Quality Manager Database200 GB to support external data.

Record up to 400 Concurrent Calls - Call Recording Only

The recommended server hardware configuration is as follows: 

Call Recording Only - 400 Calls

Running Services:RMI, CONFIG,CORE, RS/SLR, RTS, DECODER, CC IM, TOOLS, WEB UI, DATABASE

CPU

Intel 8 Core XEON (or dual socket Intel XEON Quad Core) 2.3 Ghz or better

RAM

16 GB 

HDD

Two options for recording cache (approx 2000 IOPS required by recording in peaks):

1. SSD having as a total minimum 2,000 IOPS.

2. 4x SAS 15,000 rpm for RAID 10 partition with write cache enabled to decrease HDD IOPS to acceptable levels

or a combination of both as an ideal candidate: SSD as a fast write through cache and HDD RAID 10 as a permanent storage.

Network Cards2x 1 Gigabit Ethernet
Storage Example
Average length of calls180 seconds
Average handle time270 seconds
Maximum concurrent calls400
Number of calls a day38,400 for an 8 hour day
Percentage of calls recorded100%
Storage required for one month of mp3 media720 GB + 20GB for system
Storage required for 12 months of mp3 media8.8TB + 20GB for system

 

Record up to 400 Concurrent Calls - Call Recording and Quality Manager

This scenario assumes that there will be around 50 supervisors (one supervisor to every eight agents) accessing Quality Manager simultaneously.

This scenario requires two servers:

  • Server 1: Call Recording recording and decoding modules
  • Server 2: Quality Manager including database, MLM Tools and Call Recording Web GUI

The recommended server hardware configuration is as follows:

Server 1: Call Recording - 400 Calls

Running Services:RMI, CONFIG,CORE, RS/SLR, RTS, DECODER, CC IM

CPU

Intel 8 Core XEON (or dual socket Intel XEON Quad Core) 2.3 Ghz or better

RAM

16 GB 

HDD

Two options for recording cache (approx 2000 IOPS required by recording in peaks):

1. SSD having as a total minimum 2,000 IOPS.

2. 4x SAS 15,000 rpm for RAID 10 partition with write cache enabled to decrease HDD IOPS to acceptable levels

or a combination of both as an ideal candidate: SSD as a fast write through cache and HDD RAID 10 as a permanent storage.

Network Cards2x 1 Gigabit Ethernet
Storage Example
Average length of calls180 seconds
Average handle time270 seconds
Maximum concurrent calls400
Number of calls a day38,400 for an 8 hour day
Percentage of calls recorded100%
Storage required for one month of mp3 media720 GB + 20GB for system
Storage required for 12 months of mp3 media8.8 TB + 20GB for system

Server 2: Quality Manager

Running Services:RMI, TOOLS, WEB UI, DATABASE

CPU

Intel XEON Quad Core 2 Ghz or better

RAM

32 GB RAM

HDD

Fast storage: 4 x 10,000 rpm for RAID 10

Storage required for Quality Manager Database400 GB to support external data.

 

Additional Screen Capture Requirements

Screen Capture deployments require the following hardware specifications in addition to the Call Recording or Call Recording + Quality Manager scenarios outlined earlier.

The following figures are calculated using the assumption that the estimated bandwidth required for one Screen Capture session is 400 Kbps.

Screen Capture SessionsCPUMEMHDD

Up to 500

1x Quad (2.5GHz+)

8GB RAM

2xHDD [RAID 1]

Up to 1000

2x Quad (2.5GHz+)

8GB RAM

4xHDD [RAID 10]

 

Modular Solution for 1000 Concurrent Calls

This scenario distributes Call Recording, Quality Manager and Screen Capture modules (if required) between four or five servers, which have a similar hardware configuration, differing only in allocated RAM. It is assumed that active recording will be implemented:

  • Server 1: Config, Call Recording Core, Decoder, Active Recorder
  • Server 2: Decoder, Active Recorder
  • Server 3: Decoder, Active Recorder
  • Server 4: Web Server including Quality Manager, Database, MLM Tools. If Quality Manager is not required, only half the RAM is needed.
  • Server 5: Screen Capture Media Upload Server

The recommended server hardware configuration for these servers is as follows:

Server 1: Main Recorder / Decoder

Running Services:RMI, CONFIG,CORE, SLR, DECODER

CPU

Intel XEON Quad Core E55XX 2.3 Ghz or better

RAM

16 GB RAM

HDD

Fast storage: 4 x 10,000 rpm for RAID 10

Servers 2 and 3: Recorder / Decoder

Running Services:RMI, SLR, DECODER

CPU

Intel XEON Quad Core E55XX 2.3 Ghz or better

RAM

8 GB RAM

HDD

Fast storage: 4 x 10,000 rpm for RAID 10

Server 4: Web Server, Database, Tools

Running Services:RMI, DATABASE, WEB, TOOLS

CPU

Intel XEON Quad Core E55XX 2.3 Ghz or better

RAM

32 GB RAM

HDD

Fast storage: 4 x 10,000 rpm for RAID 10

Server 5: Screen Capture

Running Services:RMI, Screen Capture

CPU

Intel XEON Quad Core E55XX 2.3 Ghz or better

RAM

8 GB RAM

HDD

Fast storage: 4 x 10,000 rpm for RAID 10

 

The overall recording parameters and storage requirements for this configuration are in the table below.

Recording Parameters

Average length of calls180 seconds
Average handle time270 seconds
Maximum concurrent calls1000
Number of calls a day96,000 for an 8 hour day
Percentage of calls recorded100%
Storage required for one month of mp3 media1.8 TB + 20GB for system
Storage required for 12 months of mp3 media22 TB + 20GB for system

Attachments:

table 10.png (image/png)
table 11.png (image/png)
table 12.png (image/png)
table 13.png (image/png)
t13.png (image/png)
t14 1.png (image/png)
t14 2.png (image/png)
t15.png (image/png)
t16.png (image/png)
t17.png (image/png)
t18.png (image/png)
t19.png (image/png)
t20.png (image/png)
t21.png (image/png)
2014-03-17_13-45-28.png (image/png)
t22a.png (image/png)
t21 2.png (image/png)
t22 1.png (image/png)
t22.png (image/png)
t23.png (image/png)
t24.png (image/png)