Survivable SIP Gateways for a Multi-site Avaya Communications Deployment
Headquartered in San Antonio, Texas, SWBC has served financial institutions and businesses across the country and individuals in the San Antonio area for more than three decades. Co-owners, Chairman Charlie Amato, and President Gary Dudley, began SWBC in 1976 to provide insurance to financial institutions. The company has since diversified to include a wide range of insurance and financial services.
Today, SWBC is a multi-faceted company with more than 1,400 employees, offices across the country, total annual premium of approximately $1 billion, and gross revenues exceeding $300 million in 2009. SWBC is licensed to market and service a variety of financial products in all 50 states, and their products are offered through several wholly owned subsidiary corporations. Although the firm is privately held, a public accounting firm audits the company's operations and financials on an annual basis.
To properly service their customer base, SWBC has developed and actively maintains a sophisticated Avaya-based contact center with applications to provide customized customer services for a range of financial institutions. Initially the contact center was solely housed in facilities in the San Antonio area, making management centralized.
More recently, geographic expansion and a series of acquisitions have added a number of new remote work centers and associated employees to SWBC. These remote sites often had older key systems or legacy PBXs from a variety of vendors, typically out of date and in poor condition. The variety of older equipment required specialized local training and support plans, making them expensive and difficult to maintain. More importantly, without being integrated into the core SWBC operations and contact center, the new remote offices could not fully utilize the contact center or other business services, limiting their effectiveness.
To integrate the new remote offices and their employees into the complement of SWBC business systems and contact center, a decision was made to use an enterprise hosted architecture based on Avaya Communications Manager 5.1.2, SIP Enablement Services (SES) at the core data center(s), and Avaya 9600 series IP Phones across the entire enterprise. To link the data centers and remote offices together, a Metro Ethernet and MPLS network would be implemented as a Wide Area Network (WAN).
However, with this architecture, any loss of WAN connectivity due to a construction accident, environmental disaster or other unplanned event would completely sever the telephone services at that site. This situation would leave those employees at the affected site without the ability to work or make emergency telephone calls. Clearly, survivability of the remote offices was a key challenge.
To address the survivability issue, SWBC and their Avaya reseller partner, Cross Telecom, implemented an architecture that would utilize a SIP Survivable Gateway at each branch office, using AudioCodes Mediant 1000 or Mediant 600 Media Gateways with optional on-board Stand Alone Survivability (SAS). Each site would also utilize Avaya 9620 IP Phones for regular staff and 9650 phones for administrative/executive staff.
In this configuration, the media gateway plays a role in normal everyday operation, terminating the on-site PRI circuit for local inbound and outbound calling. The gateway also provides FXS ports for on-site fax machines, credit card terminals and non-IP phones.
However, in case of a WAN failure, the Avaya 9600 series phones will automatically detect the outage and re-register with the SAS software within the AudioCodes Gateways (essentially a on-site SIP Proxy), allowing the phones to continue to operate in a "survival" mode (with limited features). Users at affected sites see a small icon on their Avaya IP Phone, indicating the site is operating in "survival" mode, but most common features including phone to phone calling and calls to the PSTN continue uninterrupted.
Once WAN connectivity was restored, both the Avaya 9600 IP phones and the AudioCodes Gateways would return to "normal" mode, registering with the Communications Manager in the network data center.
SWBC initially deployed AudioCodes Mediant 1000 and Mediant 600 Gateways in their Plano, Arlington, Austin, and Houston, Texas offices allowing these offices to fully integrate into the Avaya Communications Manager environment with survivability.
Many of the benefits realized with the deployment of AudioCodes Mediant Gateways, include:
- Centralized Administration – allowing the IT staff at headquarters to provision and manage new phone devices at branch offices without having to incur the cost and travel time to physically visit the site
- Cost Reductions – eliminating the older and mixed-vendor systems saved significant maintenance and management costs
- Common Dial-plan – simplifying calling into the business and between offices
- Enterprise "look" – allowing callers to be handled from any one of the remote offices without appearing as a collection of separate facilities
- Improved Scalability – enabling new sites to be brought on-board and necessary additional capacity in a cost-effective fashion
- Excellent Reliability – allowing remote sites to continue operation even in cases where the WAN might be out of service or inaccessible
- Fully Compatible with Avaya architecture
By mid-2011, SWBC plans to add their next set of remote offices into this deployment architecture, starting with their Brentwood, Tennessee facility. Additional sites are planned in the near future.