Wikipedia defines SOHO as “a category of business which can be from 1 to 10 workers.” These environments are growing as more and more people open their own office. The trend toward telecommuting is also shinking the enterprise of large offices as more and more employees work from home offices. These offices present a unique challenge in hardware and software selection as well as networking challenges.

Caskey Dickson was on the founding team of CitySearch as Director of Programming. He was responsible for the design and development of the first two versions of CitySearch's full product suite. Caskey went on to found Technocage, Inc., a custom programming organization. As CEO of Technocage, his team was responsible for the technology behind the launch of both WeddingChannel.com and CarsDirect.com. Caskey, then went on to build the enterprise technology behind LiquidWit in 2000. Caskey also works to maintain the computer networks for the Computer Science Department at LMU.
prepared by Paul Schmidt
 

A SOHO network is a myriad of connected/smart devices. A typical SOHO has few users and devices, light loads and favors ease of use over security. There is no professional manager, at home the manager might be the youngest child in the house. At one point in time SOHO was very simple but they have become more complex and some of them are subsets of the technology of enterprise networks. Smart devices are things like computers, printers, video game consoles(X-box, PS2), appliances, home automation controllers and cars. Smart appliances might include an Internet refrigerator, oven, washing machine or air conditioner. Some cars have very complex navigation systems and diagnostic systems and most cell phones are IP connected. The reason for having these devices is for connectivity, improved economy, ease of use and simple luxury. To provide good connectivity you want things to work anywhere and to facilitate communication by sharing and transferring data from one location to another. Improved economy can be obtained by controlling air conditioning and lighting so that they are switched off and on as needed. Fuel savings can be accomplished by devices that provide status messages that enable you to have fewer commutes and errands to accomplish tasks. Household security can be improved by using computer controlled and monitored security systems. All of this should be easily used in places like the kitchen where you can control things like ovens and coffee makers remotely. The setup should be easy to reconfigure as your needs change. In a less practical way, you have the luxury of being one-up on your neighbor and personally you have the gratification of using "cool" technology. For instance, you could set up your system to call home and heat up the hot tub so it is ready for you when you get there. These types of things are not always about economy and ease of use.

Types of networks available are WiFi 802.11a/b/g, Ethernet, X10 designed for home automation, and power networks. Equipment can be obtained from Linksys, Cisco (which recently bought Linksys), Apple and Belkin vendors. Connectivity can be provided by dialup modems, (asynchronous)aDSL or (synchronous)sDSL, cable modem or satellite provided by Telcos, ISP’s or TV companies. Networking is easy. A network is a system that provides direct communication to a collection of hosts. Examples are Local Area Networks (Ethernet, WiFi, Token Ring), USB: the Universal Serial Bus, and Firewire/IEEE1384. A host is a device on a network that has a unique address and is capable of sending and/or receiving data. Examples are computers and workstations, printers, NAS/Network Attached Storage, sensors and routers. A router is a host that is connected to multiple networks and selectively forwards data from one network to another. Routers may be WiFi access points or NAT boxes. A bridge is a device on two networks that is not always a host and that indiscriminately forwards data. It effectively creates a larger virtual network. A WiFi access point is an example of a bridge. Internetworking is dealing with multiple networks connected by routers. The ultimate connection is provided by the Internet that is a worldwide network of networks. It has a single standard protocol, either the older IPv4 version or the newer IPv6.

Connecting your network is done in three basic ways; remote nodes, a routed local network or by multiple local networks. A remote node network is the most basic connectivity. It connects a single host to the bigger network. The host is a distant, slow member of the larger network. A routed local network uses a router to communicate externally, to another local network, or to the Internet. Multiple local networks use a router to communicate with three or more networks and often connect wired and wireless networks.

Building your SOHO network is accomplished by providing connectivity, hosts, networks and routers to establish your own system. Connectivity to the external world is provided by dial up, DSL, cable modem, satellite or leased line. Dial up is the lowest cost but is slow and has high latency. It may be subsidized, but sometimes you have to put up with advertising to take advantage of a free service. DSL has moderate cost, from $30 at the low end up to $300 for guaranteed high speed connections. Speeds range from 128 Kbps up to 6Mbps. Latency is low, about 10 ms. There is a distance limit of 6000 meters from the DSL distribution point. There are many pricing options. There are regulatory issues, some of which are favorable to DSL, and it is not quite as shared a system as cable modems. Cable modems have moderate cost, similar to DSL. You can bundle your TV service with your internet service. Speeds range from about 2 Mbps to 10 Mbps. It is a shared medium and if too many of your neighbors are on at the same time your speed may be decreased. This is important to people who play interactive online games. There are very restrictive service agreements, you cannot run web servers. Satellite service has few geographic restrictions. There are dual modes where antennae are used for both transmitting and receiving data and single modes where the satellite data is down-loaded and upward transmissions provided by a dial up service. It is very expensive and there are variable data rates. There is inherent high latency because of the travel time lag up to the satellite and back. Leased lines are very expensive, high quality and have many options depending on service level agreements that can provide guaranteed bandwidth. This is probably beyond SOHO needs. ISDN is still around in places, but is practically dead.

Your own requirements depend on what your hosts are, where they are located, and their needs. They could be Computer/Workstations, Laptops or Home Theater PCs. Where they are located and where there are points of entry affect wired networks if there are long cable runs and it is difficult to find good access for wiring. Wireless issues are distance and whether there are obstacles to the transmission paths. Maximum distance is supposed to be about 300 ft. but in practice it is usually 50-60 ft. for good operation. You may well have a combination of wired and wireless networks. Wireless systems have problems with security. Wire networks have a 100 meter cable run limit and coils should be avoided. Avoid proximity to power lines. Purchased cables are never quite right as they come in standard lengths but they are reliable. It can be assumed that you size your home-made cables to always provide the right fit but then you need to test your cables to make certain they work correctly and manual dexterity is a requirement to make the cables. Buy wireless equipment that meets either 802.11b 11 Mbps and 802.11g 54 Mbps standards. Vendor extensions, (Multiple Input-Multiple Output) MIMO and X-speed, etc are available, but one vendor's equipment does not talk to a different vendor. Security requires defense in-depth. Anti-virus, firewalls and network security in general is required. The anti-virus software should be subscription based so it will be continuously updated. Any vendor will do. Software firewalls run on hosts and firewalls run on one host will not protect other hosts. Hardware firewalls are custom devices that are sometimes built into routers, but you still need firewall protection on your hosts. (Network Address Translation) NAT is not firewalling. Wired networks provide automatic security against outside snoopers but wireless networks do not. For protection, WEP is a poor choice. WPA is better but not perfect and standard implementations are better than non-standard. For good security on the entire system, make sure you do frequent updates. Caskey presented some pictures of common wired, wireless and combined routers. He said one fool proof way of providing a SOHO network system is by standardizing on a single vendor and using the vendor guides in your setup. This is expensive and the result will be the necessity of depending on a single source for your system needs.

Caskey Dickson presented an interesting and informative presentation on networking a high-level small office that might either be in the home or in a small part of a larger enterprise. While you may not need or want to locate your equipment all over your living unit now or intercommunicate with your entertainment systems and appliances, this type of activity will become increasingly common.

This was another of the regularly scheduled meetings of the Los Angeles Chapter of ACM. Our next regular meeting will be held on May 3, 2006. This was seventh meeting of the LA Chapter year and was attended by about 10 persons.
Mike Walsh, LA ACM Secretary