- 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.