Typical Small Business Network Topology

Around the Bay Area the kind of businesses that use the internet are broad and diverse, but some common architecture is evident at most sites with less than 20 employees. Comcast high speed business cable internet is dominating the market in the Berkeley area, with AT&T coming in close with xdsl in areas Comcast can’t serve well. A few customers are using mobile broadband and tethering phones and tablets with data to sync their computers. Frequently seen is a naked LAN behind the stock SMC modem provided to business customers. On default settings the modem responds to pings from WAN, has the default user name and password, and while it has a token firewall, it has no IP filtering or intelligence and the firewall is there to forward ports more than anything. However uncommon, it is very important to put even an entry level VPN firewall in place to provide secure tunneling, countersurveillance, and denial of service protection. From the modem to the firewall, and then to the switch where the work of the LAN is done, files are shared, printers tasked, and internal work is being prepared for its debut. Bandwidth varies with usage, but at 35 down and 15 up there are enough megabits for everyone. Credit card processing machines are often run on the fax phone line which costs an additional 30/mo. on top of the internet (~120), web hosting (~30/mo), domain (~30/yr), and IT service (~150/mo), but can be run over the net with the use of the firewall to protect its already encrypted communication. The fax machine is replaced with a networked all in one printer/scanner/copier and sometimes the fax remains but is usually made obsolete by the scanner and pdf documents. Aside from a spam and ip filter little else is necessary for a SOHO network.