You often hear about resilient networks and solutions, but what exactly does resilience mean? Is it important to your business or is it just another buzzword being used to entice you to spend money? What are the options and what should you look for? Caroline Sherry, SME Sales Manager, discusses.
What is resilience?
Internet, data and voice services play a vital role in the day-to-day running of businesses. Even though such services come with service level agreements as standard, no provider will guarantee 100% up-time for all its services. Given this situation, it is understandable that there has been a growing interest in resilience and the safeguards it can provide.
Resilience can be defined as "the ability of a system or company to recover from a catastrophic failure caused by power outage, fire, bomb or similar"*. Resiliency can also mean the "methodology you employ, and the configurations you use to make your network tolerant of failure"**. In short, it is a way of protecting either your network, the services that run over it or both, by putting an alternate means of communication in place.
Looking at such definitions you can see that, far from being used by providers as a way to get you to part with your hard-earned money, the resilience of your network and/or services can be key to ensuring the on-going success of your business. It provides you with the means to continue with business as usual, should an interruption to your primary service occur; whether it is your voice, data or Internet provision that is affected.
Resilience options
There are a variety of resilience options available depending on the type of service you have and the budget available. When reviewing these options you should consider minimising the points of failure that could occur simultaneously in your primary and secondary services. The range of options available includes:
Private Access Broadband (PAB) and ISDN back-up
Both PAB and ISDN can be used as a secondary access method for data networks and can be utilised to provide resilience options for services such as Internet and data solutions. Generally, installations specify a router with automatic failover to the ISDN back-up if the primary access method experiences an outage. Alternatively, separate routers can be provided for each service to give even greater resilience. At THUS, we have customers who have ISDN back-up to their Internet leased lines, in addition to their MPLS IP VPN network services, again minimising the impact of any fault that may occur on the primary service. In such cases, customers generally specify routers with automatic failover so the secondary resilient service kicks in as soon as a problem is detected.
Secondary circuits and dual POP site resilience:
Secondary data circuits can be used to provide resilience options for wide area network solutions - regardless of the type of traffic (such as voice, data or Internet) that the solution carries. As with the other resilience options outlined, this means that you can have a second route for your communications in case of outage on the primary circuit. Ideally, the secondary circuit would employ a completely separate route through your provider’s network and would link to a different POP (point of presence) site. The secondary circuit can be the same or have a different bandwidth to the primary circuit, allowing customers to balance risk against cost.
Duplicate services from a second provider
This method of resilience can apply to services that range from a straightforward broadband installation to complex voice solutions. Regardless of the service, this approach can be applied to almost any product. For example, at THUS we have customers who have voice services provided both by us as well as another provider. This allows the customer to use separate providers for their incoming and outgoing calls, thereby minimising the risk to their business in the event of an outage by either supplier. If, for whatever reason, either service fails the other can quickly be configured to accept incoming or outgoing calls as appropriate.
Choosing a supplier
When looking for a service with suitable resilience options, it is important to make sure that you choose a provider that practices what it preaches. Make sure that your provider has effective network management and can ensure the integrity of its own network. This should include the support of a customer service centre and network management centre, both being operational 24 hours a day, 365 days a year. Your chosen provider should also have 'Business Incident' and 'Disaster Recovery' plans, giving you the reassurance it can manage the recovery of services in a planned and methodical manner should the worst happen.
In summary
Implementing resilience options for your Internet, data and voice services can be a valuable exercise, particularly where you are using them for mission-critical business functions. Resilience can provide you with the necessary safeguards to ensure your organisation continues to operate satisfactorily in the event of service failure. Like any back-up service, resilience needs to be in place before disaster strikes. Think about your business systems and what the impact of not having them would be. If the integrity of your communications is vital, then now is the time to act.
* Definition from Wikipedia.org
** Definition from Techworld.com