1. avaya.com | 1 Avaya Aura Communication Manager Greater than 5 Nines Availability Table of Contents Executive Summary....................1 Linux Based Software.............1 Survivable Core..................2 Survivable Remote Branch......3 SIP and TDM Availability...4 High Availability WAN/LAN....4 Conclusion5 Executive Summary A vital component of Avaya Aura is Communication Manager (AACM), an industry best-in-class redundant server solution that takes into consideration the available uptime todays businesses demand. This is accomplished by utilizing the high availability standard of nines percentage approach, for AACM the availability is Greater than 5 Nines or 99.999%+. The uptime percentage of 99.999%+ equates into a downtime calculation of only 5.26 minutes or less per year. To achieve this level of availability performance AACMs has been developed with key differentiators over the competition. Differentiators include best-in-class secure Linux software, duplicated mirrored core servers, fully- replicated remote core server/servers, and fully-replicated remote branch failover servers. Avayas high availability performance is the same for both Communication Manager Non-Virtualized and Virtualized Environments. Linux Based Software Avaya Labs is continuously improving Avayas Linux based operating-system software, known throughout the industry for customized capabilities which monitor themselves, delivering built- in intelligence including self-healing abilities at all levels. Because Avaya software is Linux secured, there are fewer vulnerabilities than competitive software operating systems, adding to the 99.999%+ availability equation. Avaya Linux based software is the foundation of the ultra-reliable Avaya Aura Core including Session Manager. AACM duplicated server pairs support memory

2. avaya.com | 2 shadowing. This allows full call preservation during server interchange (no interruption in service). This is a unique advantage over Avayas main competitor because capabilities during an established call like Transfer, Hold and Conference can still take place during CM-to-CM switching. Software upgrades and patches can be performed while staying in operation and more importantly additions, moves, changes can be performed on either server pair and replicated back without service interruption, another advantage over our main competition and another element of high availability. Survivable Core Well-planned, high availability solutions include geographically- redundant Data Centers with a backup survivable core. Main Data Centers can experience service outages due to natural disasters, hardware failure, software failure, sabotage or through other means. With AACM and Avaya Aura Session Manager (AASM) in the diagram below, the survivable core includes a single server solution. Utilizing the Avaya Aura Virtualized Environment, only (3) servers are necessary to provide full featured stateful failover capabilities with automatic failback. Unique to Avaya administration can be applied at Data Center 2 during failover mode. Another advantage is AACM and AASM survivable cores can be supported anywhere on the globe with 1,000 millisecond delay. Our main competitor is limited to 80 millisecond delay or only 1,900 miles. Thats a problem with 2,475 air miles coast to coast in the continental US. In the case of another competitor, when software is upgraded to new releases, the data center cores must be taken offline to install their new core. This causes a complete out-of-service interruption limiting them to no better than 99.9% availability across typical lifecycle. Avaya Aura platform includes Mission Critical Linux software for a Greater than 5 Nines solution providing businesses the benefits to optimize their next generation collaboration solutions Unique to Avaya additions, moves and changes can be made when the Survivable Core is active, a benefit Avayas main competitor cannot provide 3. avaya.com | 3 Survivable Remote Branch Avayas Survivable Remote Branch is a green-friendly S8300 Server media module blade that fits into either the G430 or G450 Gateway. S8300 is green-friendly for two reasons: 1) Smaller footprint because the S8300 blade is contained inside a G4xx Gateway; and 2) The S8300 media module consumes only 30W compared to normal server averages of 150W. With a complete loss of the WAN or Data Centers 1 & 2, the Survivable Remote Branch takes over, functioning like a standalone system with SIP and/or TDM Trunking capabilities. Other business benefits include the following: Full feature capabilities including Contact Center, vectors, and announcements; Programming complexity is eliminated with survivable remote. Businesses benefits with lower TCO because you only need single touch administration at the main location; Upgrades and patches are pushed out from main location to survivable remotes another savings that reduces multiple onsite touches; Survivable Remote Branch contains full backup translations of the AACM Main Server pairs; Connection preserving failover/fall back, calls between two or more parties are not dropped with SIP sessions and/or local TDM Trunking. What do we experience in Survivable Remote Branch? Downtime per year 2-3 WAN/LAN outages x 3 minutes x 5% =18 to 27 seconds Average downtime experienced per end user as the result of WAN failure events (1- (27 seconds)/ (seconds in a year)) =99.99991% Include server/survivable remote and power/environment availability Branch Availability over redundant WAN link: 99.9998% x 99.99955% x 99.99991% = 99.9993% Note in Avaya labs testing the detection and failover completed on average in less than 2 minutes. Competitive Advantage: AACM and AASM survivable cores can be supported anywhere on the globe with 1,000 millisecond delay. Avaya Aura products are designed to continue service in the face of many failure events. Stable calls stay up in the event of loss of connectivity to the primary server. IP- phones and gateways do not lose registration in the event of short network outages. Such resiliency is captured in the mathematical model in assessing total system availability. 4. avaya.com | 4 SIP and TDM Availability Avaya Aura Session Manager employs Internet Engineering Task Force (IETF) standard RFC 5626 to deliver multiple, simultaneous registrations to SIP endpoints. Avaya and RFC 5626-compliant SIP endpoints can register with multiple core Session Managers and with Survivable Remote Branch for simultaneous registrations. Combined with Avayas unique application of the SIP Timer B and OPTIONs messaging, calls can be placed during network outages without dropping, and with a delay of only two seconds or less. Session Manager also supports Network Interface Card (NIC) bonding and up to 10 geo-redundant Session Manager instances. SIP and TDM Trunking complement each other in case one or the other services are lost from the PSTN. TDM Trunking is distributed across G4xx Gateways for another layer of high availability. High availability cannot be accomplished without the PSTN and the ratio between SIP and TDM trunks should be engineered and balanced according to business requirements. High Availability LAN/WAN For the purpose of meeting high availability, the recommended network topology should consist of a redundant LAN/WAN with building blocks of layered routers and switches. Multiple paths or link redundancy minimize disruption of service due to LAN/WAN failure events, link congestions, denial of service attacks, etc. When a failure in one link is detected, traffic will switch over to the healthy link. Link redundancy also accommodates the move of an endpoint or gateway from one switch to another. *According to the methodology recommended by Telcordia GR-2813-CORE, Software Reliability Prediction Avaya Aura Session Manager supports Call Preservation in the event of a network or Session Manager failure in the core. This capability allows calls in queue in a Contact Center to be processed in the normal way without any interruption or loss in service. Software quality check and assessment of software reliability: Avaya carefully examines every step of software development by measuring faults during coding phase the data used in assessing software reliability prediction* analysis involves measuring software field performance data of over 12,000 systems in the field. 5. avaya.com | 5 Conclusion Avaya Reliable Linux Software Avaya Aura Communication Manager software architecture is designed with modular functionality and a fault resistant architecture; Built on Linux, which has fewer security flaws than other operating systems and facilitates system customization to provide further security; Expert Systems with built-in system monitoring, failure detection, logging and recovery mechanisms; Software quality checks and reliability predictions at every stage of development, system test and product introduction; Years of applied dedication in software design have made Communication Manager and Session Manager a rock solid Greater than 5 Nines solution. Geographic-Redundancy Learn More To learn more and to obtain additional information such as white papers and case studies about Avaya Aura Platform please contact your Avaya Account Manager or Authorized Partner or visit us at http://www.avaya.com/usa/product/avaya-aura-platform 2013 Avaya Inc. All Rights Reserved. All trademarks identified by , , or SM are registered marks, trademarks, and service marks, respectively, of Avaya Inc. Markov Chain Reliability Modeling is used as the mathematical model for predicting total system availability. The advantage of this technique over others (for example, the parts count and combinatorial models) is its ability to capture the fault-tolerant aspect of the platform. About Avaya Avaya is a global provider of business collaboration and communications solutions, providing unified communications, contact centers, networking and related services to companies of all sizes around the world. For more information please visit www.avaya.com.