OIT Ethernet Service allows University faculty, staff, and students to connect devices to the campus data network via an Ethernet interface.
The service is available in practically every building on campus, including academic buildings, administrative buildings, and dormitories. It is also available in all eating clubs. The service is also available in some apartment buildings.
In general, OIT Ethernet Service is intended to be available only to devices registered in the Princeton University Host Database. (Temporary Unregistered Dormnet IP Service is available on a short-term basis on the Dormnet portion of the network, and is intended only to provide connectivity long enough enough for students to subscribe their computers to Dormnet.)
OIT Ethernet Service usually appears in the form of an RJ-45 Ethernet port (socket) into which you plug an Ethernet cable. These sockets are often referred to an "OIT Wallbox Ports," because each socket is often located in a box, sometimes mounted on a wall. A single OIT wallbox may provide more than one wallbox port; each is a separate OIT Ethernet port. We may use the terms "wallbox port" and "Ethernet port" interchangeably.
In these locations, OIT has already installed OIT Ethernet ports in many places where customers are likely to desire Ethernet connections. These ports are normally installed with the Ethernet port disabled (turned off) until someone contacts OIT to request that the service be turned on and to provide an account number to pay for the service.
Additional OIT Ethernet ports (e.g. more wallboxes) may also be installed as needed upon request.
To request that OIT activate existing OIT Ethernet ports or install additional ports contact the OIT Help Desk. See How to request a port activation with active IP address for more information.
To change the account to be billed for an activated OIT Ethernet port, disable an active OIT Ethernet port, or request a change (e.g. upgrade or downgrade speed) to an active OIT Ethernet port, contact the OIT Help Desk.
OIT charges a monthly fee for each OIT Ethernet port; this fee is called the "OIT Wallbox Charge." The fee varies depending on the speed of the service (e.g. 10, 100, or 1000 Mbps). The current rates for the "OIT Wallbox Charge" appear in this OIT announcement as the "port charge."
Information about all OIT Ethernet ports appears in the OIT Network Atlas. Every OIT Ethernet port is identified by a unique combination of wallbox number and socket. The database shows each OIT Ethernet port that is currently activated, its location, the account number to which it is billed, and the name of a contact at the time the port was activated. This database is used to generate bills for the monthly OIT Wallbox Charge.
Don't confuse the OIT Wallbox Charge and the Tigernet Host Charge. The OIT Wallbox Charge covers the cost of the OIT-wire connections (the Ethernet ports and Ethernet switches supporting them). It is based on OIT Ethernet port information in the OIT Network Atlas. By contrast, the Tigernet Host Charge is not associated with OIT Ethernet ports; it is associated with each device (e.g. computer, printer, etc.) registered in the Princeton University Host Database, and is based on information in that database. The TigerNet Host Charge reflects costs of the network infrastructure such as Internet fees, the network core, etc.
Once enabled, an OIT Ethernet port normally remains enabled (resulting in a monthly OIT Wallbox Charge to the account number specified at the time the port was activated) until someone contacts OIT to request that the port be disabled.
Keep in mind that not all OIT Ethernet ports are turned on. Unless someone has has contacted OIT to request that the port be turned on and has provided an account number, the port remains disabled. For examples, most offices space has one or more Ethernet ports installed, but each is disabled unless someone has contacted OIT to enable it. There are many public spaces with OIT Ethernet ports installed; in some cases a department has chosen to pay to have those ports turned on, while in others, no one has chosen to pay for the service, so the ports are disabled.
OIT Ethernet Service is installed in the following dormitories and apartments: all undergraduate dormitories, all Eating Clubs, the Old Graduate College, the New Graduate College, Butler Apartments, Lawrence Apartments, Wyman House, 11 Dickinson Street, 15 Dickinson Street, 16 Dickinson Street, 24 Dickinson Street, 24 Dickinson Street, 27 Edwards Place, 29 Edwards Place, 31 Edwards Place, 35 University Place, and 45 University Place.
In the buildings listed above, OIT has installed and activated one or more OIT Ethernet ports in each dormitory room or apartment.
Except when there is a problem associated with a device attached to an Ethernet port, these Ethernet ports are normally enabled (turned on) year-round; you do not normally contact OIT to enable or disable them.
In these locations, the number of Ethernet ports installed in each room is based upon a variety of factors, including the number of persons the dormitory room or apartment is rated to house, the configuration of the space, and the funding available to OIT (at the time the building was last wired or renovated) to provide residential networking service.
In general, each bedroom has the same number of Ethernet ports as the number of people the bedroom is expected to house. (In suites with a common room, OIT may also have installed one or more Ethernet ports in the common room, although there's no guarantee of this, nor that these additional Ethernet ports will be as many as the total in the bedrooms.)
If you believe the Ethernet ports in your dorm room does not meet these guidelines, contact OIT. E.g. if the Housing Office has assigned two people to a bedroom, but there is only one Ethernet port in that bedroom, please advise OIT and we will attempt to add a second Ethernet port to that bedroom.
Other than the situation described above, in dormitory rooms and apartments, residents normally cannot request that OIT install additional Ethernet ports. In these locations, customers with more computers than available OIT Ethernet ports may need to attach an Ethernet repeater, bridge, or switch to share an existing OIT Ethernet port among multiple clients. This issue usually arises when a resident has more than one device (e.g. two computers, or a computer and a printer), especially in dormitories or apartments that have not been renovated recently. (Buildings constructed or renovated recently sometimes have more OIT Ethernet ports than others.)
If you need more Ethernet ports than are available in a dormitory room or apartment, the OIT Solution Center will be happy to loan you an Ethernet repeater for the duration of the academic year. (You will be required to sign a form that promises you will return the device by the end of the academic year. Any device not returned by the end of the academic year will be charged to the student account of the student who signed the form.) While OIT normally does not provide explicit support for the use of private repeaters, bridges, and switches, OIT does explicitly support this particular case.
Note that the use of a repeater, bridge, or switch, while not as ideal as having additional OIT Ethernet ports, is still far better than using a Network Address Translator ("NAT", a.k.a. "NAT Router") to obtain Ethernet connections for more devices.
As University dormitories and apartments are renovated, OIT strives to install OIT Ethernet ports in such a way as to best match the current network needs of our customers.
OIT Ethernet ports in these locations are listed in the OIT Network Atlas. Every OIT Ethernet port is identified by a unique combination of wallbox number and socket. The database shows each OIT Ethernet port and its location. The database does not provide contact information for these ports. The database is not used to generate monthly OIT Wallbox Charges for these ports, as their cost is instead recovered via other means.
To be eligible for OIT Ethernet Service, a device must meet the following requirements:
As described in Which Devices Must be Registered in the Host Database?, practically every device attached to OIT Ethernet Service must be registered in the Host Database. (For students, "subscribing the device to Dormnet" causes it to be registered in the Host Database.)
When OIT is asked to provide a OIT Ethernet Service to a location, a 10Base-TX connection is what is provided unless the customer has specified something else.
Connections in dormitories rooms, apartments, and residential spaces in eating clubs are 10Base-TX; other speeds are not available in those locations.
OIT Ethernet ports configured to provide 10Base-TX service are all configured to perform autonegotiation of speed and duplex (but will be willing to negotiate only a speed of 10 Mbps and half-duplex communication). To work properly, clients must be configured to perform autonegotiation of both speed and duplex.
Clients that support 10/100Base-TX or 10/100/1000-Base-TX will work properly with these Ethernet ports as long as the client is configured to perform autonegotiation of speed and duplex. The client will negotiate with the OIT Ethernet switch, obtaining on a 10 Mbps half-duplex connection.
If the customer who requested the 100Base-TX service specified that the OIT Ethernet switch port should be configured to autonegotiate speed and duplex, then to work properly, the clients must be configured to perform autonegotiation of speed and duplex. In this situation, 10Base-TX clients will negotiate 10 Mbps service; 100Base-TX, 1000Base-TX, 10/100Base-TX, and 10/100/1000Base-TX clients will negotiate 100 Mbps service. If the client supports full-duplex operation, it will negotiate full-duplex service. If the client does not support full-duplex operation, it will negotiate half-duplex serivce.
If the customer who requested the 100Base-TX service specified that the OIT Ethernet switch port should be configured not to autonegotiate speed and duplex, but instead to be set for 100 Mbps full-duplex, then to work properly,the client must be configured to operate at 100 Mbps full-duplex, and to not perform autonegotiation of speed or duplex. Clients that do not support that mode of operation will not work properly.
If the customer who requested the 1000Base-TX service specified that the OIT Ethernet switch port should be configured to autonegotiate speed and duplex, then to work properly, the clients must be configured to perform autonegotiation of speed and duplex. In this situation, 10Base-TX clients will negotiate 10 Mbps service, 100Base-TX and 10/100Base-TX clients will negotiate 100 Mbps service, 1000Base-TX clients and 10/100/1000Base-TX clients will negotiate 1000 Mbps service. If the client supports full-duplex operation, it will negotiate full-duplex service. If the client does not support full-duplex operation, it will negotiate half-duplex service.
If the customer who requested the 1000Base-TX service specified that the OIT Ethernet switch port should be configured not to autonegotiate speed and duplex, but instead to be set for 1000 Mbps full-duplex, the to work properly,the client must be configured to operate at 1000 Mbps full-duplex, and to not perform autonegotiation of speed or duplex. Clients that do not support that mode of operation will not work properly.
It is sometimes possible for someone to intercept traffic sent to or from your computer via Ethernet networking. Modification of the traffic is also possible is some circumstances.
OIT Ethernet Service does not provide your traffic with any security; it does not encrypt your data, nor prevent your data from being deliberately modified in-transit.
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 that 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. Do not send sensitive data to web sites unless the web site connection is using strong encryption.)
OIT Ethernet Service normally provides a dedicated Ethernet switch (not repeater) port to each connection. That is, each OIT Ethernet port is normally wired to a unique port on an OIT Ethernet switch. The portion of the campus Ethernet maintained by OIT is a fully-switched environment; it does not rely on Ethernet repeaters, or on Ethernet bridges that lack switch capabilities.
An OIT Ethernet port that provides 10Base-TX service provides a 10 Megabit per second half-duplex connection between the client's Ethernet interface and the OIT Ethernet switch. Similarly, an OIT Ethernet port that provides 100Base-TX provides a 100 Megabit per second half-duplex or full-duplex (depending on configuration) connection between the client's Ethernet interface and the OIT Ethernet switch. An OIT Ethernet port that provides 1000Base-TX provides a 1000 Megabit per second half-duplex or full-duplex (depending on configuration) connection between the client's Ethernet interface and the OIT Ethernet switch.
Actual performance between the client and the OIT Ethernet switch may be lower due to overhead imposed by protocols run on top of Ethernet (e.g. IP). Some client hardware or operating systems may be too slow to make full use of the Ethernet connection.
There are normally between one and four dozen OIT Ethernet ports connected to a single OIT Ethernet switch. That "closet" Ethernet switch is typically connected to higher-capacity Ethernet switch (typically the building's "Point of Entry" Ethernet switch); that connection is typically 10 times as fast as the individual clients' connections. E.g. a closet Ethernet switch that provides 10 Mbps half-duplex connections to clients willtypically uplink to the building's Point of Entry Ethernet switch at 100 Mbps full-duplex. Each building's Point of Entry Ethernet switch is typically connected to the core of the campus network at 100 Mbps full-duplex or 1000 Mbps full-duplex.
The core of the campus network is in turn attached to the Internet and Internet2 (via multiple ISPs). As of August 2005, the University's aggregate Internet1 capacity is 115 Mbps full-duplex, and Internet2 capacity is 100 Mbps full-duplex.
One should understand that a 10 Mbps OIT Ethernet port does not guarantee the client a 10 Mbps connection to anywhere on campus or the Internet. It only provides a dedicated 10 Mbps connection between the client and OIT Ethernet switch to which it is attached. The amount of bandwidth available to the client beyond that first-hop OIT Ethernet switch will vary depending on how much bandwidth is being used by other traffic traversing the same path. For example, if there are 10,000 devices simultaneously attached to the campus network, each with 10 Mbps service, clearly they all cannot simultaneusly obtain 10 Mbps of bandwidth to the Internet. Insteach, each device that is currently communicating with the Internet will obtain some fraction of the University's Internet capacity. This relies on the fact that at any given instant, most devices are not communicating with the Internet, and those that are communicating with the Internet are usually not doing so at the maximum possible speed of their individual Ethernet connections.
OIT Ethernet Service is engineered so that the connections between OIT Ethernet switches (the uplinks which multiple clients share as data is aggregated) have much more capacity available than is usually needed, so they can handle short-term spikes as well as long-term growth. As a result, these connections rarely (if ever) experience any congestion. However, during the academic year, University's Internet connection often runs near or at capacity, particularly when some customers run software that is designed to saturate all available network capacity (e.g. most Peer To Peer ("P2P") programs).
OIT discourages, but does not forbid customers from connecting private Ethernet repeaters, bridges, or switches to OIT Ethernet Service See Connecting a Private Ethernet Repeater, Bridge, or Switch to the Campus Network for more details.
OIT discourages, but does not forbid customers from connecting Network Address Translators (a.k.a. NATs, or NAT Routers) to OIT Ethernet Service See Connecting a Private Network Address Translator to the Campus Network for more details.
OIT Ethernet Service provides IP service to those devices that are registered in the Princeton University Host Database specifying that an IP address should be assigned to the device. (The IP-SUBNET-OR-ADDRESS field is specified.)
When attached to its home network, the device network interface receives OIT Static IP Service.
If device meets the eligibility requirements for OIT Mobile IP Service, the device's network interface may also visit other OIT networks (other than its "home network") and continue to receive IP service. When it attaches via a network other than its "home network", the network interface receives OIT Mobile IP Service, not OIT Static IP Service.
Note that some network interfaces are registered in the Host Database with a "home network" that doesn't correspond to any real physical network on campus. Some of these networks include: driftnet, recyclenet, wirelessnet. These network interfaces rely on OIT Mobile IP Service; they don't receive OIT Static IP Service since it's impossible to attach them to their "home network".
If you have questions or need assistance with any of the procedures in this document, please contact the OIT Help Desk.