Building the branch office from the ground up

Inevitably, the call comes in at 4 p.m.: problems at a remote site. The network seems OK, but one server is completely inaccessible. One switch is pingable but isn’t answering a Telnet connection. There’s no IT staff at the site, and this problem has caused all work to cease. Looks like a long night for the admins.

At least it used to mean a long night. Today, it could probably be

resolved by 5 p.m., without requiring some poor IT worker to embark on a 120-mile round-trip to power cycle a server and maybe a switch. Instead, everyone heads home for a cold beer.

But there’s more to keeping the branch office running than just solidifying remote out-of-band access. An effective branch-office infrastructure starts from the ground up: power control, servers and storage, remote access gear, and practices and procedures all come into play. Doing it right requires careful planning and presents a significant financial hurdle up front, but the first time the day is saved, the cost becomes minor. The second time, the cost is forgotten.

Of course, the gear needed at the site, and your approach to managing it, will depend largely on the work the branch office is doing. But in general, it helps to think in terms of the number of workers the infrastructure will support.

Here you’ll find that the needs and constraints tend to differ significantly for a staff of one to 10 people versus a staff of 10 to 30. The smaller office necessarily requires less bandwidth, less infrastructure, and less time from administrators, whereas a branch office of 20 or 30 workers typically requires a more significant investment of all three. For offices with more than 30 employees, you’ll typically need on-site IT staff, and you’re no longer talking about remote management.

Stocking the small office

The foundation of a small office is generally a small wiring closet and nothing more. In this case, size and heat generation of any SOBO (small office/branch office) hardware is of paramount importance. There may not be room for a standard rack, but there are many options for 4U and 6U wall-mount, locking racks that can actually reduce floor footprint and provide quite adequate housing for a router and a switch -- possibly a small server. Ideally, this gear is located in the same physical location as the telco demarc (the box where your telco’s wiring ends and yours begins), as this will concentrate all infrastructure gear into one space and will reduce the potential for internal building wiring to become a problem.

Click for larger view.

In this case, smaller is definitely better, with the possible exclusion of the UPS (uninterrupted power supply). The more functions you can pack into a single form factor, the better. Cisco’s ISR (Integrated Services Routers) appliances are a good example of this. Capable of handling either an Ethernet, ADSL, or TDM handoff from an ISP, Cisco ISRs provide basic network connectivity, VPN and MPLS (Multiprotocol Label Switching) capabilities, a limited number of switch ports, wireless access, and VoIP functions from a single, centrally managed point (see our Test Center Special Report: Branch-Office Infrastructure).