Corporate converged applications often have stringent network requirements, such as delay, jitter and network availability, which can directly affect their performance. As more converged applications rely on connectionless "best effort" IP telecommunication networks, their stability and resiliency become critical. Unplanned network failures contribute to lost sales, increased overtime, reduced employee productivity and declines in customer satisfaction and loyalty.   Different approaches can be followed to implement resilient networks. However, all of them have something in common, the need for a telecommunication line backup solution. Communication line backup services offer corporate applications alternative routes to access their servers in case of main line breakouts.   Traditional telecommunication line backup challenges   Traditional telecommunication line backup scenarios, such as the ISDN service, suffer from important limitations for implementing resilient network telecommunications: The required cabled infrastructure, such as copper lines in ISDN, may not be available, nor convenient to deploy at certain locations. The limited capacity present in these emergency services leads to a significant performance decrease in corporate applications. This issue becomes a big concern for mission critical applications, where an availability loss caused by a line failure may be unaffordable.   Benefits of redundant telecommunication lines through 2G/3G cellular routers   The stability achieved in recent 2G/3G networks makes cellular telecommunication technologies the best complement to landline services for the support of top quality corporate backup services. In addition, thanks to the DSL-like bandwidth available in recent 3G implementations, the corporate application availability loss is highly minimized.   Without the need of costly copper line deployments, the firm's network resiliency is enforced in a rapid and cost effective way.   Network resilience with the Teldat cellular router telecommunications backup solution   Teldat cellular routers have proven their success in secure and reliable telecommunication backup services for the Small and Medium sized Business, as well as in corporate branch offices. Through a simple cellular router deployment the network resilience is enhanced, while fast return on investment is assured.   Innovation, engineering quality and Teldat's expertise in cellular router solutions are combined to offer the utmost reliability and versatility in the cellular telecommunications access. The dual SIM support provides a failsafe backup over an alternative cellular provider - i.e. Carrier Diversity. Teldat's cellular backup performance is optimized with software-driven cellular failure detection techniques. Furthermore, the per SIM dual APN attachment permits "out-of-band" management of the router, in analogy to the managed land line services (learn more about Teldat cellular routers).   The vast protocol and functionality suite supplied by the business-graded Teldat Internetworking Software (CIT), not only guarantees interoperability and carrier-class manageability, but it also supports VPN's - with hardware boosted data encryption-, QoS, advanced routing and many other features. Thanks to the CIT, corporate network resiliency is achieved, and the cellular router telecommunication backup services are implemented with an optimal efficiency, leading to a rapid ROI, as well as customer satisfaction and loyalty.

Network Resilience Scenario I A stand-alone cellular router backing up a branch office network
The Teldat H1+ cellular router is installed on the corporate LAN and it is continuously supervising the main service router (CPE in the figure) status with VRRP, HSRP or dynamic routing (RIP, OSPF, BGP).   Upon a main line failure, the cellular router takes the main role in order to exchange the corporate traffic over a 2G/3G network with additional IPSec encryption.   Teldat NSLA / NSM   A finer and complementary router supervision is also available to cover scenarios with delay-sensitive corporate applications, such as Voice and Video: The Teldat cellular router continually supervises the main link delay and jitter performance. If these values drop below pre-defined thresholds, the cellular router backup switching takes place.   Other router options G1 router+for GPRS / EDGE G1-CDMArouter for CDMA2000 1xRTT H1routerfor UMTS / HSDPA / HSUPA H1-CDMA 3g enabler for CDMA / EV-DO		Click into image to enlarge

Network Resilience Scenario II A cellular router backing up a branch office network with LAN Bypass
The Teldat cellular router Atlas 50 is installed between the office LAN and the main service router (CPE). The cellular router supervises the main link performance through the Teldat NSLA / NSM. Should the main router link performance drop under pre-defined thresholds, the Teldat cellular router switches to 3G automatically. As in Scenario I, the backup switching is transparent to the office PC's.   The LAN bypass feature It is the Atlas 50 cellular router’s unique hardware feature that eliminates the single point of failure of the Atlas 50 router in this network scenario.   Upon a power outage, the two Atlas 50 cellular router Ethernet ports (Eth1 and Eth2 in the figure) are hard-wire connected, so that the CPE can deliver the main link access to the LAN PC's, no matter if the Atlas 50 is powered up or down.		Click into image to enlarge

Network Resilience Scenario III A single Teldat cellular router delivers main and backup services over 3G

The office front end equipment is a Teldat modular router (Atlas x50) that combines a plug-in interface card for main router link and another one for the cellular router backup. The main access can be either land line (ADSL, GigabitEthernet, TDM, etc) or via the cellular router's telecommunication line.		Click into image to enlarge