In my earlier post, I covered the SBA and what I feel are some pretty significant downsides given the technology changes in the past 10 or so years. So what are the options?
Redundant WAN
The simplest option, from an SfB point of view, is to have redundant connectivity from your branch office to your main office. How you go about this can vary. You could get a 2nd line from the same carrier, but that doesn’t help you if that carrier suffers an outage. A different carrier would guard against that, though watch out for the 2nd carrier simply using the first carrier for all of part of their services. Even with two different carriers, you could wind up with fibre in the same conduit, and you may suffer the dreaded backhoe fading.
Backup VPN
A backup VPN might make more sense. An Internet connection is less expensive, and there’s a good chance that it’s not sharing much or any infrastructure with the WAN link. The first issue to watch out for with VPNs is that you may not have sufficient upstream bandwidth. The second is that you may not have sufficient bandwidth at all. If you are using a lower capacity link as a backup, you can use the DSCP markings that you applied to your SfB traffic for QoS (you did do QoS, right?) to help you out. Your firewall/VPN device can be set to prioritize voice traffic based on these markings, and potentially block video all together.
Use SfB Server Standard Edition instead of an SBA
If redundant connections aren’t feasible, using a Standard Edition server may be. This moves all of your users functionality to their location, preventing the ugliness of limited functionality mode. However, you now have to license this server, and you’re no longer dealing with an appliance – though you’ll recall that some SBAs were just servers with PRI cards anyway.
More downsides here are that if a user homed on this server hosts a meeting with a large number of participants from outside their office, all of that traffic is going to hit the WAN. Also, if the users in this office work remotely a lot, all of that traffic transits the WAN to reach the Edge servers at the main office…. unless you deploy an edge in the branch office, and now it seems like we’re boiling the ocean and building rocket ships to guard against a branch office WAN failure.
Get Out of the Office
The last option to deal with a branch office outage would be to get out of the office, either virtually or physically.
SfB has excellent mobile clients. If your users are homed in a central office or a datacentre, they can use the mobile clients to connect to their pool over LTE. There may be some limits here, like not being able to be a member of a Response Group, but as a backup option this one is pretty simple, and your staff may all already have company phones or subsidized company phones.
Lastly, the users can find a different place to work. This could be home, it could be a co-working space, or a coffee shop.
What about Hybrid and Cloud?
Finally, if you’re in a hybrid or cloud deployment, I’ll provide some thoughts on how to handle branch offices in the next two posts.