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AustinTek Wifi homepage

Joseph Mack

jmack (at) austintek (dot) com

Aug 2007


Table of Contents

1. AustinTek Wifi Services
2. What happens at when the location is wifi-enabled?
3. How wifi works (the technical stuff)
4. The Installation Process
5. Security
6. The differences between Permanent and Temporary Installations
7. Image from Outdoor Event
8. Contact Information

1. AustinTek Wifi Services

AustinTek provides wifi connectivity for conferences, meetings, outdoor events, and installs permanent wifi setups for businesses. We work in the RTP (Durham, Chapel Hill, Cary, Raleigh, Wake Forest) and nearby Triad area in North Carolina. Service outside this area can be arranged.

Wifi is a technology that allows computers to communicate via a radio (wireless) link. Since the computer no longer requires a cable for network connection, wifi allows

  • people with portable computers (e.g. laptops and PDAs) to stay connected while they move from place to place
  • people to be connected at places where there is no fixed network connection. This could be for a visitors at a work place, or for attendees and exhibitors at a conference or at a business show or convention.

2. What happens at when the location is wifi-enabled?

  • You let the users/attendees know that you have wifi connectivity and to bring their 802.11b/g enabled devices (e.g. laptops, PDA).
  • On connecting via a wifi link (to a wireless access point - WAP), the user, the customer and the exhibitors, have the same internet connectivity as at home or at work.

    They can -

    • send e-mail and images anywhere they like (e.g.off-site)
    • retrieve e-mail from their off-site e-mail machine
    • surf the web
    • exchange e-mail and files with other users/attendees
    • access information provided on the local fixed network which might be
      • web and file servers containing class materials
      • announcements, schedules for the day
      • view images from wifi cameras, showing events at other locations.
      • receive streaming audio/TV
    • work in privacy. This might allow a parent to bring children to an event, knowing that they can sit and work while the children have fun, when previously they would have had to choose between not being able to do their work or not coming at all.
  • Press/Media people can send their on-site copy and images, getting the story out promptly.
  • Exhibitors can access their off-site databases, records and promotional materials, and enter orders in realtime, rather than having to enter them on a laptop and then move them over by hand on return after the show.
  • We can set up a local web site, showing maps, schedules, food menus and prize lists.
  • We can connect up your servers containing materials for the attendees.
  • We can provide webcams, for sites spread over a large area (several rooms or a large outdoor event), making images available for people to check activities at other locations in the event.
  • We can coordinate broadcast of local streaming video/audio.
  • We can provide an external web site to promote businesses and events to people who can't be there physically. This website can include images from the on-site webcams.

Where WAPs are spread over a large enough area, a treasure hunt can center around finding the WAPs, and on completion, winners can receive a "Wifi Master" button.

3. How wifi works (the technical stuff)

For permanent installations: we install the equipment, integrate it into your infrastructure and train your staff to run it. For installations with no staff available and minimal infrastructure (e.g. coffee shops with only one sales person), we offer a turnkey solution that requires minimal attention from staff.

For shows and conferences: we setup the equipment and provide the staff to run it. We provide help for users wanting to connect.

Users need an 802.11b/g enabled computer or PDA. Newer laptop computers already have these. Earlier laptops require a a pcmcia wifi card costing about US$25-75. For a PDA, you can clip in a similar device. The radio link replaces an ethernet cable, allowing the computer to be networked (as long as the user stays in wifi range).

At the other end of the radio link is a wireless access point (WAP) which is connected to (part of) the cabled (fixed, wired) network. The range available, about 100yrds, is limited by design, so that people in proximity can have their own wifi links without mutual interference. The 100yrd range allows people to move about an office or to be in range of a WAP at a restaurant or tent at an outdoor event. Visitors can join the network without needing to be plugged into a spare ethernet jack and can work anywhere they're comfortable.

For operation over a larger area, multiple WAPs are used with roaming, allowing the user to move from place to place while staying connected.

We provide the connectivity between the wifi enabled computers of the users/attendees, the computers of the customers, and the internet.

We use the connectivity to the internet already available locally e.g. local DSL, T1, dial-up, or we provide/install the connection.

We provide a wifi server box (Linux) that serves dhcp to the wifi enabled attendees (gives the portable computers an IP, so that they can connect), static IPs for the customer's computers, a router, webcache, firewall, local ftp and a scratch area for windows filesharing.

High availability (automatic software failover to duplicate hardware on standby) is available as an option where the network can't be down for the time it takes to fix problems with the network. This is the default setup for shows and conferences.

4. The Installation Process

  • WAPs

    We install the WAPs.

    You must provide somewhere safe (weather, theft, damage) for them. The WAPs need 120V and a cabled connection to the network (we will coordinate this with the people on-site).

  • wifi server

    We provide the wifi server (a machine running Linux).

    The wifi server

    • allocates dynamic IPs to the portable computers (via dhcpd), allowing them to join the internet.
    • is a firewall, with rules to the customer's requirements. This regulates access between the fixed network, the portable computers and the internet.
    • is a router to the internet (sends packets to and receives packets from the internet).
    • has a webserver for a local website - this website can show maps, schedules, food menus, prize lists...
    • has a webcache to accelarate throughput of webpages from the internet.
    • forwards outgoing e-mail
    • has a scratch area for sharing windows files
    • has an ftp site

    Also available, as an option, is a a high availability failover pair. On hardware failure, a backup machine automatically takes over when the active machine fails. This is for situations where the wifi cannot go down for the time it takes to fix a hardware failure.

  • access to the internet

    You provide access to the internet (if needed).

    If an on-site internet connection is not available, we can provide it (e.g. through a satellite connection).

  • webcams

    We provide them and connect them up to the local website. If you want images relayed off-site, for people who can't attend, we handle that too.

    Like the WAPs, they need 120V power and a safe location (but we'll install them).

  • external website

    We can provide an external web site to promote businesses and events to people who can't be there physically.

5. Security

Wifi is a broadcast medium - anyone close by with a wifi card can pick up the radio signal. To prevent interception of the content, the signal must be encrypted. Encryption requires the user to have a key (shared secret). Several levels of security are available:

  • none: In some installations e.g. restaurants, coffee shops, college campuses, apartment complexes, hotel guests, where convenience of access is more important than security, or it's impossible to keep the key secret, encryption is not used. Users must understand that their network traffic can be intercepted (users can set up their own vpns or do their own encryption and still be secure). These installations can run without staff intervention and need minimal maintenance.

  • WEP: WEP was the first security standard devised for wifi. WEP is breakable by an observer who intercepts a sufficient number of wifi packets and for this reason, the key should be changed at intervals. WEP provides a minimal level of security and prevents anyone but a determined intruder from being able to join the network. For some installations (e.g. workplaces and libraries, conferences) WEP is used to prevent unauthorised access to the network by people looking for a free ride, rather than to provide absolute security. WEP is suitable for networks with a small number of users (e.g. the home), where you can control the number of people with the key and you don't want the neighbors using your network.

  • WPA: WPA is a recent security standard for wifi and encompasses a number of unbreakable encryption schemes. WPA is required for any environment where security needs are absolute (e.g. HIPAA, internal access within a business). WPA requires that encryption keys to be setup in the laptop. In the case of a stolen or lost laptop, the keys can be revoked and the stolen/missing laptop will not be able to access the wifi network. WPA does not work with some older wifi cards (new wifi cards are about $25).

  • authorization/authentication WEP and WPA will allow anyone with the laptop to access the network. For ultimate security, you can also require the user to enter a password before being allowed to access the network.

In all cases we can install (or train your staff to install) the encryption keys.

6. The differences between Permanent and Temporary Installations

Table 1. Differences between Permanent and Temporary Wifi Installations

parameter Permanent Temporary

Staff to operate installation

We train your staff

We provide the staff

Help with users

We train your staff to help the users and provide documentation.

We help users

hardware

We provide the hardware

(we can install or upgrade your fixed network too)

You provide hardware (we will suggest hardware and providers)

or we will provide the hardware (your choice).

software

We provide the software

We provide the software

connectivity guarantee (our installation, not power or internet connection etc)

8hr day, 128 users.

No downtime warrantees.

Free software calls for 90 days.

Service contract available after 90days.

less than 15min down time, no penalty

15-30min down time, half fees charged for day

1hr downtime (or more), no fees charged for day

firewall warrantee

Warrantee is difficult once we hand over control to your staff. However we're happy to discuss this further.

Penalty of half fee for day, if someone can demonstrate, to staff, access from the outside to a wifi connected computer. Max penalty, one intrusion/day. No warrantee for intrusion by computer coming in over wifi.

7. Image from Outdoor Event

Here's Joe providing wifi connectivity for a 5-day outdoor event for 500 people in the Fall of 2003. Internet connection was by satellite. (From Joe's chin, this is day 3 or 4). Who said wifi is wireless? (image is a thumbnail, click for a larger image).

Figure 1. Outdoor Event for 500 people

8. Contact Information

Joseph Mack
e-mail: jmack (at) austintek (dot) com
phone: (919)-401-2047
Durham, NC. 
		
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