• GMC Motorhomes International, a motorhome club made up of owners of the classic motorhome throughout the US and Canada. At the March 2010 convention held at Montgomery, Texas I presented a session about wireless access to the internet using Wi-Fi and Mobile Broadband technologies. The paragraphs below contain the text from the document that was distributed to align with the presentation. The presentation, in PowerPoint format, may be downloaded from here.

Wireless for the
Wondering Wandering

The GMCer’s Guide to Over-the-Road Internet Access
by Byron Songer
This information augments the presentation given at the Spring 2009 Convention of GMC Motorhomes International.

Introduction

There are two ways of using a personal computer to access the Internet while traveling in a GMC MotorHome. One is by accessing a Wi-Fi connection at a campground or other hotspot. The other involves subscribing to a mobile broadband service from a cellular carrier. There are advantages and drawbacks to each type of infrastructure. Having a knowledge of these can help the GMC owner decide which is better for personal use.

This document presents the two methods of Internet access as well as ways they can be enhanced or expanded. Also explained are some of the limitations that may be encountered. I’ll begin by providing a brief overview of the Wi-Fi technology and it’s inherent characteristics before moving on to the values of mobile broadband access.

Wi-Fi, what it is and what it isn’t.

If you’ve been in an airport, coffee shop, library or hotel recently, chances are you’ve been right in the middle of a wireless network. Many people also use wireless networking, also called Wi-Fi or 802.11 networking, to connect their computers at home. There is a growing list of places that provide Wi-Fi access. Some facilities provide the service at no charge while others charge some type of fee. Some may require the use of a password or user account while others are totally open.

Wi-Fi is a marketing term that was developed in the late 1990’s to signify a product’s adherence to certain standards so that one manufacturer’s equipment would function correctly with another manufacturer’s networking components. Adherence to these standards makes it possible to own a computer of one brand and access the Internet through another manufacturer’s network components.

Wi-Fi uses a two-way radio signal instead of wires to complete the connection between your computer and a wired connection to the Internet. The business end of a wireless Internet connection is usually high-speed DSL, cable or T-1 line. Performance while accessing the Internet will vary based on the number of active users or the type and amount of data being transmitted at any point in time.

Wi-Fi uses certain frequencies of the radio spectrum for sending and receiving data. Most wireless network devices operate at the 2.4 GHz range. Since Wi-Fi operates as a radio, it must be able to transmit and receive to function correctly.

A few of the attributes and elements of Wi-Fi radios are as follows:

Transceiver: The ability to both transmit and receive at specific, federally approved frequencies.

Antenna: Most antennas are integrated into wireless cards or the body of the laptop computer. In some cases, it’s possible to add an external antenna to improve the signal.

Code/Decode: Known as a codec, this is the method by which (among other things) digital data is converted into a radio signal and vice versa.

Spread-spectrum signal: High-frequency radio signals used by 802.11 are both low-powered and susceptible to interference. Wide-band, spread-spectrum radio signals aren’t as sensitive to interference as narrow-band signals — and they’re quite efficient at getting the most out of the limited power. They also help in avoiding traffic jams among radio signals, which makes it possible for several Wi-Fi transceivers to operate at the same time.

What is a Hotspot?

The basic definition of a hotspot is a wireless local-access network (WLAN) that’s open to the public. So, you ask, what is a WLAN? It is nothing more than a collection of computers, printers and other devices networked together using the 802.11 standard (Wi-Fi).

There are two basic elements to a WLAN; client systems and the wireless access point.

Client: Any computer included in the WLAN, accessing the Internet via the access point, is known as a client.

Access point: An access point is a Wi-Fi transceiver that’s connected to the Internet through communications devices that vary based on whether the connection is for a home or major business. The access point serves (distributes) the Internet connection to the client computers within the network. In a home situation, the access point also functions as a router between the local network and the Internet.

Hotspots are WLANs open to the public, but you typically need to provide a password before you can open a hotspot’s gateway to the Internet. You can think of an access point like a castle that freely drops the drawbridge over the moat, allowing entry into the gateway tunnel, but opening the gate to the interior only after the visitor gives the proper password.

By the way, it may be helpful to know that Apple has trade named is Wi-Fi compliant products AirPort. Apple refers to the access points as base stations. This naming structure has nothing to do with interoperability with other devices or components. It only has to do with branding.

What about wireless providers such as Boingo?

Boingo is a “network of networks.” They are a provider of hotspots in places such as airports, coffee shops and some hotel lobbies. Boingo works with the top Wi-Fi operators all over the world — T-Mobile, AT&T, Sprint, iBAHN, Wayport, British Telecom and more — and combines them into one big network that you can access with a single user name and password.

More about Wi-Fi

Today, it’s almost impossible to buy a laptop without a built-in wireless transceiver. Moreover, it’s now fairly easy to set up a wireless Wi-Fi network that provides high-speed internet access, network file-sharing and all the other benefits of a wired network. Wi-Fi makes it easy to connect computers, printers and smartphones into a single communication network without having to string wires around your motorhome.

Walls and other equipment indoors interfere with the radio signal and reduce the radius of effective wireless coverage. You can expect to get an effective 100 foot radius of indoor service from a router or AP, and almost 300 feet outdoors (where there are fewer obstacles to interfere with the radio waves). Keep in mind that 802.11 networking is a “line of sight” type of radio service. Major obstacles in the line can interfere with the signal. Likewise other types of equipment, such as a microwave oven, can also interfere with the Wi-Fi signal.

Flavors of 802.11 wireless

All wireless network devices are based on the IEEE’s 802.11 standard, but there are three flavors commonly implemented:

The original standard, 802.11b, is still quite common. It operates at 2.4 GHz and generally achieves 6 Mbps of actual data transfer. One reason that rate’s so low is that in this frequency range interference from other wireless devices like phones, other notebook computers or even microwave ovens slow the signal.

802.11g, a faster and more widely implemented standard, uses a higher bit-rate along with lower frequency band of “b”. Real-life throughput is about 25 Mbps though it’s possible to achieve 54 Mbps in an ideal environment. The area of coverage is less than 802.11b. “G” equipment is backward-compatible with the 802.11b standard if set as such. However, a mix of b and g equipment forces the g products to slow for coexistence with b traffic.

802.11n, the current standard, delivers higher throughput – up to 50 times greater than 802.11b, and 10 times greater than 802.11g. Though awaiting final ratification there are some products touted as being “802.11n-compliant”.

Location is important

It may sound simple, especially in the midst of all the chatter about bit-rate, throughput, and frequency range, but the single most important issue when setting up a Wi-Fi network is probably where the access points are placed. APs are simply radio transmitters and receivers. For indoor installations, walls, air conditioners, copying machines, windows, and metal objects can stop the signal dead. Likewise, in an outdoor setup trees, buildings and motorcoaches can effect the signal as well as seasonal characteristics. If access points aren’t carefully placed and correctly tuned, some network users won’t be able to maintain a reliable network connection, especially if they move their computer from one place to another.

Not all networks are equal

Two of the more common complaints about accessing Wi-Fi in a campground involve signal strength and performance. Unfortunately, there are many variables involved in using an 802.11 network.

As mentioned, the most critical element is where the access points are located. Subsidiary to this is whether an antenna is used, the power setting of the unit, the channel being used, and existence of other things that may cause interference.

Of course, since the radio in your computer is a transceiver, the type of antenna embedded in the body has an effect. To overcome the deficiencies of a built-in components its possible to utilize a USB-based device. Some have small antennas that can be raised while others may have an antenna jack. Using an antenna can help on the client end of the situation and overcome some of the idiosyncrasies of the campground’s setup.

When it comes to performance there are other issues involved. Accessing a Wi-Fi hotspot means communicating with a shared resource. A big variable is the number of active users on the network. Of course, the access point is, ultimately, connected to an ISP through some type of modem. There are varying speeds of cable and DSL modems. The higher the speed of the service the more costly it is for the campground. Obviously, if a location is cutting costs by subscribing to a less expensive internet connection, performance will be slow.

Mobile Broadband

If you frequently camp in parks away from a Wi-Fi hotspot or want use of the Internet while traveling down the highway then accessing a Mobile Broadband service may be the thing for you. Today’s smartphone users with data plans are already using the built-in facility of internet mobility. It’s possible to get the same service (without telephone access) for your laptop through the use of a USB-based cellular data modem.

Exactly what constitutes Mobile Broadband has evolved. It doesn’t signify just any mobile capability. Today, if it doesn’t meet the criteria for being 3G (3rd Generation) then it generally isn’t accepted as being broadband. That means that the GPRS and EDGE networks of the recent past and that still exist, don’t qualify. What users want today is 3G or EVDO Rev A technology.

Today the top three providers of mobile broadband are Verizon Wireless, AT&T and Sprint (which is resold by Virgin Mobile). Of course, to take advantage of the faster mobile networks, the mobile device you choose must also be capable of supporting the faster speeds. All of the network cards currently offered by the these carriers support 3G and EVDO Rev A. Not so for all smartphones so make sure the one you choose meets the broadband criteria.

Mobile Broadband services are not a substitute for a standard cable or DSL internet access in the home. Providers charge for levels of service based on monthly data transmission. Other typical limitations of Mobile Broadband is that providers may restrict or limit large data exchanges, such as streaming audio/video, VoIP and automated feeds.

Coverage and service plans

In terms of coverage, look for a service that provides high quality connections where you’ll need them most (the locations where you travel frequently).

One other thing I’ll point out is that the major carriers listed provide monthly service plans to which you subscribe for a contract period. Virgin Mobile, however, has a pay-as-you-go service that isn’t based on a contract. Access to the service is by purchasing their Broadband2Go USB device. For occasional users this is the best plan.

Availability of Mobile Broadband has expanded tremendously in the last 18 months. In general, population centers have the best coverage followed by major thoroughfares, i.e. Interstate Highways. Penetration into more rural areas has improved but lags behind to some extent.

Mobile Broadband and Wi-Fi

For the more technologically-oriented and internet-needy among us it’s possible to merge the technologies of Wi-Fi and Mobile Broadband for great advantage. Sprint’s MiFi accomplishes this purpose with a small, 802.11 router and cellular data modem integrated into one case.

My preferred alternative to the MiFi are two products that work well together; Virgin Mobile’s Broadband2Go and CradlePoint’s PHS300 Wi-Fi router. Using the Virgin Mobile device you get pay-as-you-go access to Sprint’s broadband network at an affordable price. The PHS 300 redistributes the internet access via 802.11 b/g while plugged into power or if operating on rechargeable battery. And, should 4G technology replace the current broadband technology, upgrading performance is easily accomplished through the use of a newer USB device. Another advantage the CradlePoint has over Sprint’s MiFi is that it offers a greater range beyond 25 feet.

In summary

GMC travelers have options for accessing the Internet while away from home. Having an understanding of the advantages and limitations of each system can result in a less frustrating user experience.


Tags: Wandering Wirelessly