Campus and Building Networks
Network Upgrade Project
Beginning October 2004 and continuing through March 2005, LTS/Technology
Management Services (TMS) will be replacing the old network hubs and switches
with 200 new Cisco switches in 68 academic/administrative buildings on the Asa
Packard, Mountain Top and Goodman Campuses. Over 7000 network jacks will
be upgraded. This is a complex and large effort but the benefits will result
in:
1. Improved network throughput through switching technology rather then shared hubs.
2. Properly configured networked printers.
3. More sophisticated tools
allowing TMS to protect the campus from crippling viruses and denial of service
attacks.
4. A good network infrastructure for creating and authenticating wireless networks.
5. The elimination of under-configured
and failing older equipment which is creating performance problems.
6. A consistent set of equipment
for the entire campus making maintenance and lifecycle replacement tasks more
efficient and cost-effective.
The project will be implemented in stages to minimize the network outage impact to the campus and especially to our classrooms. We understand there is no good time to have the network down and thus appreciate your understanding in this effort as we improve this vital University resource. In some areas the resulting network topology will require address changes these are indicated on the schedule below. But, unless static addresses are used for computing devices such as printers, computers should not require changes and should connect to the new network after a reboot. All wireless services will be programmed for authentication. Check the wireless site for wireless authentication instructions.As part of this effort the IPX protocol will no longer be supported on the Backbone Network. The LTS public computers listed at the Libraries and Computer Sites are an available resource during scheduled outages. Contact the Computing Consultants assigned to your department if you need assistance with any computing devices due to this upgrade. The Help Desk (x8-help or x8-4357) will have information if there are any changes to the schedule. Individuals may review the schedule of network upgrades in order to plan their work activities.
General
Technology Management Services (TMS), a division of Library and Technology Services (LTS), supports over 10,000 wired data network connections to most buildings on the Asa Packer, Mountaintop and Goodman campuses. This backbone network is gigabit fiber, routing IP protocols.
Building networks are principally 10 Mbps switched Ethernet on Category 3 twisted-pair copper cable. There is limited Category 5 twisted-pair copper cable installed and at these locations 100 Mbps switched Ethernet service is provided. Gigabit over Category 6 copper installations are occurring as building network upgrade funding becomes available.
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Backbone
router with fiber connectivity to Ethernet switches and cabling in remote buildings. |
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|
Category
6 (1000 Mb or gigabit) cable & Ethernet switch |
Category
3 (10 Mb) cable & Ethernet switch |
Two Internet gateways are available to all campus network connections. The commodity Internet gateway operates at 100 Mbps as does the research-oriented Internet2 gateway. Shoud the commodity Internet gateway fail for any reason, a 45 Mbps gateway is available for backup.
Wireless data networking is an emerging and enabling service that is built on top of the wired network. The current standards supported are IEEE 802.11b and 802.11g. Encrypted security for a wireless session is done on a wired network port bases using 802.1x and Protected Extensible Authentication Protocol (peap). Therefore, any wireless device cannot use wireless services until it is properly configured and a valid Lehigh ID and Password are provided to the authentication process. Any wireless device (notebook, PDA, PDA/phones, hand-held game devices, etc.) must be capable of 802.1x and peap in order to use the wireless data network.
New Network Connection Requests
Faculty and staff requesting new network connections need to complete a work order request. More information about lead times and costs is also available.Network Troubles
Faculty and staff experiencing network troubles should refer to our documentation for guidance on reporting and resolving network problems.
Students experiencing network troubles should follow the instructions on the trouble-shooting guide on the residential housing WIRED Home page.
Network Troubleshooting & Technical Information
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Network Interface Cards (NIC) and Auto-Negotiate settings
If the speed and duplex settings are not properly set to match the characteristics of the building network, errors may occur resulting in a “sluggish” connection. Setting the NIC to auto-negotiate the link speed in a building with category 3 wiring may also create slowness.
Example: If the NIC and connecting switch port are set to auto-negotiate they will sync up at the highest speed that the two devices are able to run, typically 100 Mbps. However, the auto-negotiate process cannot determine the quality of the cable between the NIC and the network switch. A negotiated speed of 100 Mbps requires category 5 (or higher) cable. But if the cable segment is category 3, the mis-match will result in a link speed (most likely) slower than 10 Mbps.
Please contact your computing consultant to determine the best NIC settings for your specific location.
- Switched Network Port settings
Buildings with category 3 cabling (runs 10 Mbps only) the port speed is set to 10Mb and the port duplex is set to Auto.
Buildings with category 5 or 6 cabling (runs 100Mbps or 1000Mbps, respectively) both the port speed and the duplex is set to Auto negotiate
- Routers, Bootp servers, Domain
Name Servers (DNS), Dynamic Host Control Protocol (DHCP) server and wireless
access points.
As devices become more sophisticated, they often bring capabilities that can negatively impact a building’s network by conflicting with the campus network devices providing the campus-wide central services. These devices may make the building’s network inoperative, may redirect network traffic improperly, or may create sluggish performance.Be a good network neighbor. DO NOT attach or configure routers, bootp, DNS servers, DHCP servers or wireless access points at your network jack. Contact your computing consultant if you have questions about the impact of configuring these services.
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Mini-hubs or mini-switches and Ethernet addresses
There are times when clients need additional network connections, but it is impractical or cost-prohibitive to provide additional cable and network jacks in an area. In this case, a mini-switch may be useful. This device allows several computers to share one network jack. Consider the amount of traffic the connected computers will generate before considering this option. Since all traffic will share one port, it would not be effective to run two servers through a mini-switch. To control network security all wired jacks are limited to eight Ethernet addresses, i.e. the nineth device attached will fail to get an IP address. Turn off spanning tree if the switch acquired supports this features as it conflicts with network operations and will result in the port cycling between an off and on status every five minutes. Please note that intelligent switches may have other features such as routing which may cause network problems. Contact your computing consultant if you need further assistance or evaluation of your situation.
CDWG can supply mini-switches. We recommend the Allied Telesyn models because they are cost-effective and work well with our network. The AT-FS700 series provides a powerful 10/100 switching solution to desktop and small network environments. They are available in 5, 8, and 16-port models, with pricing ranging from $25-$90.
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LTS Cable Length Standards
The cable from your computer NIC to the network switch (not the wall jack) cannot exceed 100 meters. If the cable length exceeds this standard, cable errors will occur, dumping additional packets onto your connection, resulting in a slower connection. LTS’s campus standard cable distance will not exceed 95 meters from the wall jack to the network switch port. This leaves 5 meters for the network cable which attaches between the network jack and your computer. If you require a network cable longer than 5 meters, please contact your computing consultant who can determine if a longer network cable will put your connection out of spec and cause errors.
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Network Cable Type
A network connection is only as fast as its slowest link. Another issue which can lead to poor network performance is cable errors which occurs by mismatching the cable type of the network cable and the network link segment or using a damaged network cable. Errors will occur if the network cord is kinked or the connectors damaged.
TMS recommends that all network cables be Category 5e cable for 10/100 Mbps connections and Category 6 for 1000 Mbps connections. The University Bookstore carries the appropriate network cables. However, if you need many cables or cables of varying lengths, ask your Computing Consultant for help in locating a supplier to obtain better pricing.
Network Policies
A view of part of the Network Operations Center, showing some of the
servers and consoles.