OIT Temporary Visitor Wireless Network Access (TVWNA, pronounced "tuna") provides short-term Internet connectivity to wireless devices brought by visitors to Princeton University.
The service is available in most buildings on the main campus; see OIT's Wireless Coverage Map.
TVWNA is intended to provide service to wireless devices belonging to short-term visitors. It provides service to a device on up to seven days within a calendar month. TVWNA is not intended to provide service to devices belonging to Princeton University faculty, staff, and students, or to longer-term visitors. It does not provide service to wired-only devices.
TVNWA should not be confused with Visitor IP (VIP) Service, a different service that provides Internet connectivity to wired devices brought by visitors to Palmer House (a University guest house).
To get started using TVWNA right away, you may follow these instructions:
A detailed list of these locations is not available, but a rough guide is available in OIT's Wireless Coverage Map (a Java-based version is also available).
The way you perform the steps above is different for every operating system; if you need a detailed step-by-step procedure for your computer's operating system, consult the instructions that accompany your operating system. The OIT KnowledgeBase contains configuration procedures for several common operating systems; see Wireless: OIT Visitor Wireless for short stays on campus using PUvisitor (FAQ).
The remainder of this document contains more details about TVWNA, as well as information that should assist you in troubleshooting any difficulties using the service.
A device must meet the following technical requirements to use TVWNA:
More information about the wireless hardware supported by OIT Wireless Service is below, in Wireless Hardware and Configuration.
If registered devices try to use the service, they will not be able to associate to the Wireless Access Point (i.e. connect to the puvisitor network).
The service does not support computers with broken DHCP client software, clients with only BootP (not DHCP) software, or clients that require a static IP address or hostname.
Our current convention for the Internet hostnames associated with TVWNA IP addresses is: tvwna-LETTER-NUMBER.princeton.org, where LETTER denotes which OIT DHCP server owns the TVWNA IP address. This convention may change in the future.
The Identify My Computer tool will identify the IP address and hostname your computer is currently using, and also tell you if it is a TVWNA IP Address.
We limit how long a particular client may use TVWNA. We do so to discourage abuse by clients whom TVWNA is not intended to service; to discourage faculty, staff, and students from using TVWNA as an alternative to registering devices in the Host Database. We also do so to help preserve an adequate supply of IP addresses for legitimate TVWNA clients.
A device may use TVWNA on any seven days within a single calendar month. We define "use" as any time during which the device was leased a TVWNA IP address. Any use on a day counts, regardless of the length of use on that day.
Once a device has used TVWNA on seven days within a calendar month, the device is declared a TVWNA Camper. (The device may use TVNWA throughout the seventh day; once the seventh day is over, it is declared a TVWNA Camper.)
A TVWNA Camper cannot use TVWNA during the remainder of that calendar month. The wireless hardware addresses of current TVWNA Campers appear in Devices Blocked from Temporary Visitor Wireless Network Access.
If a TVWNA Camper tries to use TVWNA, it will not be able to associate to the Wireless Access Point (i.e. connect to the puvisitor network).
You may determine how many days during the current month your device has used TVWNA; you will first need to discover your device's wireless hardware address. Look for that hardware address in Temporary Visitor Wireless Network Access Clients This Month.
If your device is currently using TVWNA, its hardware address will also appear in Current Temporary Visitor Wireless Network Access IP Address Assignments. And if your device has already been declared a TVWNA Camper, its hardware address will appear in Devices Blocked from Temporary Visitor Wireless Network Access.
At the start of each month, the list of TVWNA Campers is cleared. You can review historic lists of TVWNA Campers from several past months in Old TVWNA Campers.
If a device is declared a TVWNA Camper as a result of seven days of TVWNA usage during the first fifteen days of a month, and this happens for three months in a row, the device is declared a Persistent TVWNA Camper.
A Persistent TVWNA Camper cannot use TVWNA for a year. The year starts on the date the device was declared a Persistent TVWNA Camper.
If a Persistent TVWNA Camper tries to use TVWNA, it will not be able to associate to the Wireless Access Point (i.e. connect to the puvisitor network).
The wireless hardware addresses of current Persistent TVWNA Campers appear in Devices Blocked from Temporary Visitor Wireless Network Access. The date on which the device was declared a Persistent TVWNA Camper appears, along with the months of TVWNA Camping that contributed to the devices being so declared. A device is removed from the list one year after the date it was added.
Keep in mind that TVWNA is intended to serve short-term visitors to the Princeton University campus. Princeton University faculty, staff, and students are not expected to use TVWNA; they are expected to instead register their devices in the Princeton University Host Database. Princeton University faculty, staff, and students should not use TVWNA as a substitute for registering their devices in the Host Database and using the OIT network services intended for their use. Misuse of TVWNA by Princeton University faculty, staff, and students violates our acceptable use policy for the service; in such cases, the device may be blocked from further use of the service, and/or the matter may be referred to an appropriate University authority.
Long-term visitors are expected to be visiting at the invitation of some University staff or faculty member. That person (the University sponsor of the visitor) should register the device in the Princeton University Host Database, much like any other office device at the University.
TVWNA is intended to function as an "Internet Hot Spot," providing Internet connectivity to visitors. It's not intended to provide these visitors with access to services that should be available only to "on-campus devices" or "Princeton University" devices.
Accordingly, TVWNA clients enjoy the same access to the campus network as do devices elsewhere on the Internet. That means, for example, that they cannot access campus services specifically configured to serve only on-campus devices.
The IP addresses and DNS hostnames assigned to TVWNA clients are distinct from those assigned to devices registered in the Princeton University Host Database.
TVWNA is currently based on the IEEE 802.11b and 802.11g standards. (These are sometimes referred to as "Wi-Fi.") Our service uses 802.11g, and includes backward support for 802.11b.
The service does not support equipment based on the IEEE 802.11a standard. (That is sometimes referred to as "Wi-Fi5.")
The service does not support equipment based on the IEEE 802.11n standard. The 802.11n standard was ratified only recently, in September 2009. (802.11n equipment currently available is based on earlier drafts of the standard.)
The service does not support BlueTooth wireless equipment. BlueTooth is a short-range wireless standard for extremely short-range connections (e.g. among a mouse, a keyboard, and a computer workstation).
Our services supports data rates of 5.5, 6, 9, 11, 12, 18, 24, 36, 48, and 54 Mbps. (802.11b clients will only be able to use data rates of 5.5 and 11 Mbps.)
We do not support data rates of 1 and 2 Mbps, because clients communicating so slowly (either due to poor signal or lack of support for 802.11b) would monopolize the available bandwidth, leaving little for faster clients.
We do not support IEEE 802.11 clients (i.e. those that predate 802.11b), because those clients only support data rates of 1 and 2 Mbps, neither of which we support.
Some vendors sold 802.11g equipment before the standard was finalized in November 2001; this equipment was based on earlier drafts of the standard. Some of these early 802.11g devices may experience compatibility problems both with 802.11b networks, and with other vendor's 802.11g devices. Some 802.11g devices that do not yet comply the final version of the 802.11g standard may even interfere with surrounding 802.11b networks. If you have an 802.11g device, contact the the vendor for updates to bring it into full compliance with the final version of the 802.11g standard. If you have difficulty using an 802.11g device with TVWNA, also try reconfiguring it to limit itself to 802.11b.
All the TVWNA Wireless Access Points are configured to provide a wireless network with the single network name: puvisitor. The network name is sometimes referred to as the SSID (Service Set Identity).
Any wireless client you wish to use with TVWNA should be configured to connect specifically to the network name puvisitor.
We use 802.11 "open" authentication, not 802.11 "shared" authentication.
Clients that can support 802.1x authentication should disable this when connecting to TVWNA. The service does not currently use 802.1x.
TVWNA does not use a network password (e.g. WEP key, WPA key, WPA2 key). (It did until January 5 2006.)
TVWNA supports moving from one Wireless Access Point's coverage area to another overlapping coverage area without restarting the computer.
It is extremely simple for someone to intercept traffic sent to or from your computer via wireless networking. Modification of the traffic is also possible.
We do not attempt to secure TVWNA using encryption technologies. Those encryption technologies that all wireless clients support (e.g. WEP using a shared key) are ineffective. Newer encryption technologies are not supported by many potential TVWNA clients, and even so, most of these technologies rely on there already being a different secret shared by each client and the network (e.g. an individual user's password), which is not available given that TVWNA customers are not "known".
As you cannot rely on the network to prevent interception or modification of your data, if your data is sensitive, you would be prudent to take steps to ensure that anyone who might intercept your traffic would find it of little value, and to take steps to make it difficult for an interloper to modify your traffic in-transit. For example, instead of using applications that send and receive your data in the clear, use applications that use strong encryption before placing your data on the network. (E.g. avoid cleartext telnet, ftp, and rlogin; instead use ssh, scp/sftp, kerbererized telnet, kerberized ftp, or kerberized rlogin. When using ssh/scp/sftp, verify that the public key of the server to which you are connecting is legitimate. Do not send sensitive data to Web sites unless the Web site connection is using strong encryption and you verify that the Web site's public key is legitimate.)
In particular, Princeton University blocks certain kinds of traffic at our Internet connection, typically for security reasons. This includes, for example, NetBIOS-over-IP, SNMP, RPC portmapper, and NFS. Software that relies on blocked traffic will not be able to communicate with other devices on the Internet. (The most common software of this sort include Windows file and printer sharing, and some Microsoft email applications.)
If you need to access such services provided by your home institution, check with your home institution to see if they provide a way for Internet users such as you to connect to their network via VPN. We do not prevent TVWNA customers from establishing VPN connections to VPN servers on the Internet, and we do not block NetBIOS-over-IP, SNMP, RPC portmapper, and NFS traffic travelling over such VPN connections.
In particular, the current DHCP specification has evolved rapidly in recent years, so older client software may not work right. If the DHCP specification changes in the future, you may need to update the DHCP software on your computer so it may use TVWNA.
Some client DHCP implementations or configurations may have problems that are not apparent when they are only used in an environment where the same IP address is always assigned to a client. These clients then encounter problems when trying to use TVWNA.
When we discover a DHCP client that function in such a way as to interfere with TVWNA, we may declare the device ineligible for TVWNA. A list of devices that have been declared ineligible appears in Devices Ineligible for Temporary Visitor Wireless Network Access.
The most common DHCP client malfunctions of this sort include ignoring DHCP lease times (continuing to use an IP address after its lease has expired), or running multiple DHCP clients on a single interface (hardware address).
A list of devices ineligible for TVWNA appears in Devices Ineligible for Temporary Visitor Wireless Network Access. That document includes list of TVWNA Campers, Persistent TVWNA Campers, devices that have been declared ineligible for TVWNA due to other reasons, and devices that have been declared ineligible for all wireless services offered by OIT.
Sometimes devices are declared ineligible for TVWNA (or all wireless services offered by OIT) because they are infected or compromised, then attempt to break into other devices, or attack other Internet destinations.
Check the the Devices Ineligible for Temporary Visitor Wireless Network Access
document to learn whether your device has been blocked, and why it has been blocked.
If you don't find your device there, be sure to also check
Devices Blocked from Temporary Unregistered Dormnet IP Address Service,
Devices Blocked from Visitor IP Service,
and
Devices Blocked from Mobile IP Service,
as devices blocked from those services also are blocked from TVWNA.
If at some later time, the blocked device is registered in the Host Database,
it is possible (but not guaranteed) that OIT will attempt to contact someone
responsible for the now-registered device, to advise them of the block.
Such notification is not immediate; it may take several
business days after the device is registered in the Host Database before
such notification happens.
While using TVWNA, you may use the
Identify My Computer tool
to discover the DNS hostname and IP address in-use by your computer.
If you rely on any services or software that expect your computer to be using a
specific IP address or Internet hostname, they may not work when your computer
is using a temporary IP address and Internet hostname.
For example, if you subscribe to a commercial network service that only accepts your
connection from your own corporate or home network (based upon IP address or Internet hostname),
you may not be able to connect while you are using TVWNA.
The same may be true if you use licensed software that is customized to only run if your
computer is attached to your own corporate or home network.
Our current convention for the Internet hostnames associated with TVWNA IP addresses is:
tvwna-LETTER-NUMBER.princeton.org,
where LETTER denotes which OIT DHCP server owns the TVWNA IP address.
This convention may change in the future.
While using TVWNA, you may use the
Identify My Computer tool
to discover the DNS hostname and IP address in-use by your computer.
Most often this is because the client's association attempt is rejected (e.g. the client
is not eligible for the requested wireless service), and the client simply
retries at a high rate.
Other times this is because the client is succesfully associated to the Access Point, but has a poor quality
connection, so it chooses to disconnect, then immediately tries to reconnect.
To reduce the impact these clients have on network service,
OIT limits the frequency at which a wireless client may request an association to
any single OIT Wireless Access Point.
Currently, we allow a wireless client to request an association up to three times
within a two-minute period for all wireless services
(e.g. OIT Wireless Service or TVWNA) provided by the OIT Wireless Access Point.
After three (successful or unsuccessful) association requests, that
particular OIT Wireless Access Point will reject any further association
requests from that particular wireless client for two minutes.
Even with this rate limit in place,
wireless clients that continuously connect and disconnect at
a very high rate on an ongoing basis day after day
still place a high enough load on the service as to degrade service for
other customers.
Typically these problematic wireless clients
lose connectivity within a few seconds of connecting, and reconnect
immediately, and then lose connectivity again, round-the-clock.
To maintain an acceptable service level for properly functioning clients,
OIT may mark the problematic clients ineligible for wireless services
provided by OIT.
Use of TVWNA by devices that should not use TVWNA (for example,
devices belonging to Princeton University faculty, staff, and students, or to longer-term visitors)
exacerbates this, reducing the number of TVWNA IP addresses available to legitimate short-term visitors.
Devices belonging to Princeton University faculty, staff, and students, or to longer-term visitors
to the network should be registered in the
Princeton University Host Database; they should use
OIT Wireless Service rather than TVWNA.
If your client is unable to connect to the puvisitor wireless network, or obtain an IP address, check for the following common problems:
Also verify that the hardware address does not appear in
Devices Blocked from Temporary Unregistered Dormnet IP Address Service,
Devices Blocked from Visitor IP Service,
and
Devices Blocked from OIT Mobile IP Service.
(Ineligibility for any of those services makes a device ineligible to use TVWNA.)
So if there was a problem that prevented your client from connecting, and you have
since corrected the problem, your client may not actually try to connect
again even though it may appear to you that it is trying and failing.
You may need to reboot the client to force it try anew.
In some cases, even rebooting may not help; to force the client
to try anew, you may have to delete its definition for the wireless interface
and re-enter it.
If you have questions or need assistance with any of the procedures in this document, please contact the OIT Help Desk.