Dalton Cardiovascular Research Center

Wireless networking enables several systems to communicate to a wired network infrastructure without the constraint of a physical wire; allowing greater mobility within a designated area. MU's campus network, each network port at the wall costs $13.50/mth to have active. The way Wireless works, 1 network port can be shared to several computers via a WAP (basically a wireless router) thus negating the needto pay for more network ports. Although wired network hubs/routers are illegal on MU networks, DoIT/Telecom have not ruled out Wireless Access Points (WAP) they deploy, but we cannot install our own WAP's.

Wireless networking is a replacement of the single patch cable that plugs into the back of your computer to the network outlet in the wall with a two part system. At the wall, a Wireless Access Point (WAP) is plugged into the network outlet much like your computer was. This WAP translates the networking (ethernet) signal into a radio frequency very similar to that used by 2.4 and 5.0 Ghrz cordless phones. You computer then has a wireless network card installed internally, PCMCIA, PCI or USB which picks up this signal and converts it back into digital signal. In concept, very much like a modem translates analog to/from digital signal when you Dial-up to a provider like AOL, EarthLink or TigerLink. Each WAP can produce a signal up to 20 - 100 feet depending on the surrounding environment and can communicate to several wireless network clients at once. Again, DoIT provides WAP's and Dalton covers the monthly fees that go with them.

New technology such as 802.11n can achieve high rates of bandwidth over 'b' and 'g' protocols, but is very new and just hitting consumer mainstream. Campus currently only supports 802.11g and b. A consumer WAP costs between $60 - $200, while the commercial ones deployed by DoIT run $200 - $800. Additionally any computer needs to have a wireless network card that costs $40 - $120.

1. Bandwidth. The standard wireless technology implemented on campus is 802.11g which allows a maximum of 54Mbps, but realistically will rarely exceed 20 - 25Mbps total. In comparison a direct network port connection from the wall to your computer allows for a dedicated 100Mbps (10x's the speed) within the campus network and 768Kbps out ot the internet. In July of 2008, DoIT will be increasing wired bandwidth to 1Gbps for on campus and 3Mbps.
    
   802.11g is backwards compatible with 802.11b wireless cards. If just one 'b' type card connects to a WAP, all connected computers are slowed down to the 'b' speed (11Mpbs Max shared), which is just a 5th of g's speed. The WAP's DoIT deploy are a bit more advanced and are better at compensating and switching bandwidth to clients to increase performance, but over-all everyone connected still affects each other's bandwidth.
    
   
2. Currently, Hospital faculty/staff (those that logon with the UMHS-USERS domain and have a true E-mail of sso@health.missouri.edu), cannot access certain Campus resources that require authentication while wireless. This includes Dalton file servers (M:, P:, V: drives), other campus departmental servers, etc. We do not have an exact answer as to why this suddenly stopped working in June '09 for wireless users, but DoIT has made it clear it is not a priority for them to resolve and thus it becomes a drawback to wireless.
    
   
3. Of the available wireless bandwidth is shared amongst all computers talking to the same WAP, effectively 5 - 10 computers simultaneously working will only achieve 1 - 2Mbps. Even then if just one of those computers transfers a large file it will hog a majority of that bandwidth, seriously impeding other computers from network access for the duration of the transfer. Thus the greater number of wireless devices the slower everyone goes.
    
   
4. Wireless systems cannot be accessed directly from the wired network or other wireless devices unless you use a 3rd party peer-host-source type system like GoToMyPC which requires a monthly fee. This is done as a security pre-caution and exceptions cannot be made.
    
   
5. Wireless is not nearly as stable/protected as a wired connection because it relies on common frequencies (2.4Ghrz) that many other non-networking wireless devices also use. They can interfere with the signal causing “bouncing” connections, degraded performance or longer sessions of outages. Due to this nature, wireless is much more difficult to trouble-shoot and DoIT puts it lower on its priority list when problems do occur.
    
   
6. Most wireless cards do not "initiate" or connect until after you log onto the system. This is especially true for USB and add-on wireless cards. Since you normally log onto your computer with your E-mail ID/PWD, you computer needs to be able to talk to the Campus Domain servers to confirm you entered your credentials correctly. If the wireless card isn't active it cannot do this. Most OS's will cache your profile so if the network is not available, it will compare what you type against the 'cached' info. However, if you've never logged on to the computer before with some type of network available that can reach the MU Domain controllers, then you will not be able to log in. This is usually frustrating in Labs that have high student turn over.
    
   The VPN client can be set to launch prior to logon. By starting, sometimes it will 'jump-start' the wireless card. However, this is completely dependant of the wireless card and its drivers.
    
   
7. Each WAP has an area of effectiveness that degrades with distance and interference. Certain areas may get poor signal strength and/or quality further slowing speed. Objects like metal cabinets, Faraday cages, anti-shatter mesh in doors, pipe-chasing in walls can all block signals. Items like Refridgerators or centerfuges are even more interferring; both due to the metal they are made of and teh RF frequencies generated by their motors.
    
   
8. DoIT has made itself clear that if too many wired connections are dropped in lieu of wireless usage, it will reconsider the current cost status of wireless for that building. (a.k.a. they will maintain a certain amount of income for usage in a manner they see fit).
    
   
9. Some wireless cards are not compatible with our TigerNet1X method of authenctiation (802.1X). These systems would require the users to learn to load the VPN client before they could access printers, file server, server based apps or other network resources local to Dalton or other buildings behind the TigerNet2 firewall.
    
   
10. In a wireless network the WAP becomes a single point of failure for all computers attached. If the WAP were to malfunction or be interfered with, those computers will be without network connectivity until the WAP is fixed, replaced or the interference is removed. 802.11b runs in the 2.4Ghrz frequency, which is also used by cordless phones and they can conflict with each other. Even a lab with a 2.4Ghrz phone down the hall could potentially disrupt the wireless infrastructure in your lab. 802.11g, probably the next 'mainstream' wireless technology and what DoIT will eventually move to, runs at the 2.4 and 5Ghrz frequency. The latest cordless phones also run at these frequencies. 900Mhrz phones will not interfere with Wireless.
     
    

See all the above questions. DoIT has indicated, initially, that even when they implement Wireless there will only be the single port charge required by the WAP. However, if revenue from normal network drops falls below a certain threshold, there will be adjustments to the cost of that 1 port servicing the WAP.

Dalton currently covers monthly cost for 9 WAP's throughout the building. If costs increase, that may be passed down to the labs.

Bluetooth is indeed a wireless technology, however is different from Wi-Fi. Currently Bluetooth is geared to very short range use. For example, from your computer to your mouse/keyboard, syncing your PDA with your computer and/or printing to your office printer. Bluetooth has a range limitation of approximately 6 - 10 feet. How Bluetooth evolves and if it will ever cross-over into the networking scene is yet to be seen.

It depends on your platform and the quality/features you want on your device. First make sure your system doesn’t already have a built-in wireless card. Most laptops under 5yrs old do. Almost all PC desktops do not. Mac desktops that are 2yrs or newer probably do. Ask if you are unsure.
 
Basic USB wireless cards for PC’s run between $30 - $50. Slotted cards run between $40 - $100. Mac AirportExtreme’s are $49. (prices do not include shipping). Card with longer antenna’s (for better reception, i.e. systems that are surrounded by file cabinets or faraday (sp?) cages) are higher priced.

DoIT started implementing wireless at Dalton in August of 2004. Hardware installation followed in September and from that point on they are in control of wireless at Dalton. Even though they are responsible for the hardware, please contact Dalton Computing Support for any problems you encounter. DO NOT call the help desk unless dalton support is not available by pager or E-mail.

There are roughly 9 WAP's throughout Dalton providing connection to almost every area of the building. Although some areas may have poorer quality due to equipment in labs.

Initially TigerNet was the only option, using WEP security. However, the need for more secure structure brought about TigerNet1X which uses 802.1x security in conjunction with your E-mail ID/PWD. TigerNet1X was a trusted network, so if you are connected to it, you do not need to use the VPN client to connect to the file server, public printers, lab computers at Dalton lab or any other TigerNet2 resources. TigerNet requires the VPN client to be launched prior to accessing these resources.
 
Mid 2008, MizzouWireless was brought up as yet a 'more' secure network using WPA-Enterprise (a variation of 802.1x) and is replacing both the prior networks.
 
If you ever see any other wireless networks at Dalton do not connect to them as they are probably somebodies miss-configured Laptop. However, sometimes, ghost networks appear if you were previously connected say to Paneara, Starbucks or home wireless network. Until you reset your wireless card it may show that that network is available when it actually is not.

DoIT has declared this as illegal and, if detected during their routine scans, the shared port will be disabled until they are satisfied usage is back in compliance.
 
Technically, yes. Currently DoIT is unable to feasibly track down ports in which routers or ICS sharing is in use. ‘Feasibly’, in that it’s possible for them to detect, but it takes more time and slows traffic down for the building/network segment, so they still may choose to do this type of check, but less frequently than other less effective methods. That being said, we (Dalton IT) cannot support such usage, nor do we have the resources in which to manage and maintain consumer grade routers for all labs. Commercial grade routers that can be centrally managed run $1000 or more each. In addition, by hiding systems in this manner, there are other drawbacks, such as if you wanted to access a hidden system from off-campus (e.g. use Remote Desktop). You would have to utilize a 3rd party peer-host-source type system, such as GoToMyPC which has a monthly charge and thus negate cost savings of not using an active port.

1. You are required to purchase a rack mountable hub that will be stored in the Telecom closet (˜$70 - $150) . This will allow you to utilize the existing ports in your lab without having to re-run cable everywhere.
    
   
2. You will not have access to any shared resources outside of your hub, nor will any computers outside the hub be able to see into this ‘private network’.
    
   
3. Sub Question: Why can’t we just build our own internal Network?
   1. Cheap $49 hubs cannot handle large amounts of traffic. Even though your PC is not in use, even if it’s turned off, the network card is sending/receiving packets. This ‘chatter’ overhead in addition to frequent bandwidth usage by several systems requires more robust switches that manage the traffic. A managed 8 port version starts at $200 and they go up to $800.
       
      
   2. Building our own “internal infrastructure” would require more attention from our current IT workload as it must be designed, maintained and diagnosed completely by us (DoIT isn’t going to help). This would be something that the Director and Investigators would have to meet and agree on. i.e. no simple matter even if equipment wise it’s not that big of a deal. There’s DHCP, DNS and other issues to contend with.
       
      
   3. Resources such as the file server would be require to be ‘dual-homed’ between both networks. This can cause issues of its own. Other resources such as printers would require a server intermediary or you would have to purchase enterprise class printers (over $1000) that allow for multiple network interfaces.
       
      
   
    
   

Yes. However, although unlikely, be aware that the way DoIT scans for multiple systems on a given port (each computer has a unique MAC address that identifies it), if you switch too much too quick (say several times in an hour), you may be unlucky and their scan occurs at the same time. When multiple nic’s are detected, DoIT will deactivate the port and contact DCRC IT. We will then have to explain and get the port reactivated. There is no way to anticipate when scans occur as they are automated and their timing is based on the scanning servers workload, current bandwidth and other factors we cannot predict/control.
 
Again, unlikely, but there is the potential to have some disruption in service.