Service Level Agreement for Network Service


  1. About this Agreement
  2. Introduction and Model of Operation
  3. Network Services
  4. Network Performance
  5. Network Support

1 – About this Agreement

This agreement outlines the network services offered by ComTech on behalf of the NC State community. This agreement is intended to document procedures for support of campus data networking services and get service level expectations for these services. Further, this document specifies ComTech service level commitments applied to network performance and support for all Network and OIT Desktop and Application Support customers. This agreement is reviewed annually and approved by the Associate Vice Chancellor for Finance and Information Systems and the Vice Provost for Information Technology.

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2 – Introduction and Model of Operation

Communication Technologies (ComTech) is the network service provider for the NC State University community. These services include connectivity and switching as well as advanced network systems and management functions. Operationally, ComTech designs, implements, and maintains NC State data communication networks.

Data Networking

  • The NC State network (NCState.Net) provides for computer communications between campus end systems. Additionally, NCState.Net provides gateway access to campus resources from remote sites and access to the internet and advanced research network.
  • ComTech installs and manages campus network devices, including desktop switches, building aggregation switches, server aggregation switches, backbone switches, and gateways.

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3 – Network Services

ComTech provides campus data network services to college, departmental, and central administration IT groups. These IT groups serve as the customers of record. The ComTech data service provides for network connectivity from the desktop switch or server aggregation switch. Inside wiring between the end system and the ComTech electronics is installed and maintained by the installation and maintenance group within ComTech. ComTech Network connectivity includes:

Switched Ethernet LAN access

Ethernet LAN access is offered in all campus buildings connected to the campus fiber backbone and wired according to the campus standard wiring plan. LAN access provides for physical connectivity of end systems to the campus data network via standard Ethernet (10 Mbps), Fast Ethernet (100 Mbps), and Gigabit Ethernet (1000 Mbps) network switches. End systems include desktop systems, servers, printers, and the like.

Campus data transport

The NCState.Net backbone provides a logical overlay network supporting the open internet protocol (IP) version-4 bearer service. Campus data transport includes:

  • IP bearer service
  • IP multicast

Remote access to the public network infrastructure

ComTech provides remote access to campus resources through public network gateways. ComTech works with public network providers to implement and maintain network connections between off-campus NC State facilities and the NCState.Net backbone. The public network service provider is responsible for the leased line between the remote site and the NC State campus proper. ComTech provides and supports the network electronics and addresses on the NC State campus and remote sides of the leased line connection.

Internet gateway service

ComTech maintains an external gateway connection to the commodity internet and advanced research networks via the North Carolina Research and Education Network (NCREN) and the North Carolina Networking Initiative (NCNI) GigaPop. Internet gateway service includes:

  • Commodity internet
  • Advanced research networks; e.g., vBNS, Abilene

Host registration and naming services

ComTech administers domain name servers in support of IP host address to name resolution. In addition, these servers support unity database information, off-campus resolution requests, and campus resolution requests.

Dynamic Host Configuration Protocol (DHCP) provides an automated mechanism for assigning IP host addresses. ComTech supports static DHCP assignment for an end system attached to the NCState.Net backbone. LAN Administrators must first register the end system address for DHCP hosts. All residence hall hosts receive IP addresses dynamically using ComTech-supported DHCP

Firewall Services

ComTech offers redundant managed firewall services to isolate and protect critical network hosts to the campus community. Please call the Network Operations Center ( NOC ) at 919.513.9675 to set up an appointment to discuss your firewall needs.

Wireless Service

Wireless access is offered in various locations across campus. The ComTech wireless network implementation is part of a campus-wide Nomad Computing Environment. The Nomad Computing Environment uses Dynamic Host Configuration Protocol (DHCP) to provide ubiquitous and seamless mobile computing resources. The NC State wireless network infrastructure allows portable computing devices with wireless network interfaces to connect to the NC State network.

Conditions and Expectations

ComTech provides the services mentioned here with service level guarantees described in the remaining sections of this document. We can provide service level guarantees within NCState.Net supported infrastructure. ComTech does not guarantee support or service level for the following:

  • Legacy equipment and technologies – ThinNet (Ethernet 10base2)
  • Internet access beyond the NC State gateway
  • Internet performance
  • Any network device not maintained solely by ComTech

4 – Network Performance

Network performance is specified in terms of reliability and responsiveness.

Network Reliability

Network reliability is measured in terms of network availability or uptime.

  • ComTech implements advanced network architectures according to industry standards. Generally speaking, network availability is directly related to the amount of redundancy in the system. This redundancy is realized in duplicated network links and equipment. ComTech includes the following in the NCState.Net backbone architecture to increase availability and minimize downtime.
    • Redundant backbone switching equipment
    • Redundant links in the backbone
    • Alternate paths in the backbone
    • Dual power sources in the backbone; e.g., campus power, diesel generator
    • Onsite spares for all equipment used in the campus infrastructure
    • Maintenance contracts on network equipment
    • Redundant internet gateways
    • Alternate internet gateway paths
    • UPSs in all campus telecommunications closets
  • ComTech monitors the availability of all backbone interfaces, i.e., buildings. In addition, ComTech agrees to provide an end-to-end data service that offers annual availability of 99.5% (less than 43.8 hours of downtime).
  • Network availability measurements will be compiled using a combination of ServiceNow and network management system reporting functions.

Network Responsiveness

Network responsiveness is measured in terms of response time and throughput.

  • The NCState.Net backbone is based on a non-blocking architecture with links sized to minimize delay and maximize throughput at peak load. ComTech continuously monitors network performance and applies equipment and link upgrades to maintain optimal delay and throughput characteristics. ComTech monitors the performance of:
    • Backbone switches
    • Internet gateways
    • Remote gateways
    • Building backbone links
    • Backbone links (between backbone switches)
  • ComTech agrees to provide non-blocking (i.e., line-rate transport free from network congestion) backbone network performance.

5 – Network Support

ComTech provides support for all network services listed above. ComTech relies on departmental LAN administrators to support local connectivity issues, i.e., the interface between the user system and the desktop switching equipment. College and departmental primary LAN administrators will be complete or part-time “permanent year-round” NC State employees. There should be at least one alternate LAN administrator meeting the above criteria to fill in for the primary if the primary is not available. In addition, part-time “temporary” personnel, including students, may be used to assist in the administration of LANs.

LAN Administrator responsibilities

  • Information for requesting data patching information can be found at
    • ComTech will do data patching of the closet end for all types of cable.
    • Three working days is a typical turnaround time for routine activations. Most are done within a day. Regular activations are 8 hours to 3 days.
    • If ComTech must perform an emergency activation (requested within 8 hours), then a charge of 1.5 time and tech labor costs will be billed. Please call the Network Operations at 513-9675 or email for current rates.
  • Ensuring hosts connecting to LAN are correctly configured so as not to interfere with existing network services.
  • Registering end systems in the host registration database.
  • Level 1 support, i.e., initial investigation of user problems; determining whether the problem is user error, application/PC malfunction, or apparent network problem.
  • Reporting network problems to ComTech as appropriate
  • Assisting ComTech in determining additional network needs
  • Reporting conditions that could impact network services within the LAN

Network Trouble

  • ComTech employs a 24-hours-per-day, 7-days-per-week, 365-days-per-year pager rotation schedule; i.e., ComTech staff respond to network outages at any time without exception. Problems shall always be reported by opening a ServiceNow call and assigning it to ComTech or sending an email to (an email to this address automatically opens a ServiceNow call). In addition, urgent problems may be reported by phoning the network manager or the network operations desk directly (see Appendix A). Trouble reports shall be reported by LAN administrators and shall include at a minimum the following information:
    • Contact information
    • Description of problem
    • Location of the problem (campus, building, floor, room)
    • Relevant network addresses (i.e., IP and MAC addresses)
  • A ComTech staff member will acknowledge a problem reported via ServiceNow (or trouble alias) within two hours of posting by contacting the reporting LAN administrator. A ComTech staff member will acknowledge a page from the network manager or the operations desk within 30 minutes of receipt. ComTech will respond with problem resolution using ServiceNow and assign calls back to the customer to close the original call.
  • ComTech continuously monitors the campus network for outages, sub-optimal performance, and service degradation. Upon detection of a network outage, ComTech will alert customers via a Network Activity Alert email message. Periodic updates will be issued as new information is available. A final Network Activity Alert will be sent when service has been restored. Suppose the outage affects critical devices or services. In that case, emergency contact procedures will be enacted—ComTech archives backbone equipment logs and Network Activity Alert messages for future review and problem determination.

Network Abuse

  • Network abuse is a use of the network by an end system that either interferes with normal network operation or is otherwise in violation of NC State network acceptable use policy (AUP).
  • Violations of the AUP include but are not limited to network denial of service (DoS) attacks, unauthorized port scanning, and attempts to gain unauthorized access to network hosts.
  • Reports of network abuse should be sent to Abuse reports should contain contact information, the offending host’s IP or end system address, and a log showing evidence of the reported abuse.
  • Upon notification of abuse, ComTech will apply a network filter for the reported host, acknowledge the complaint, and notify the LAN administrator of the offending host. The LAN administrator is responsible for correcting the host and requesting that the filter be disabled.
  • ComTech maintains network configurations under industry-defined “best practices.” Specifically, ComTech configurations include safeguards against the use of the NC State network as an amplification site for denial of service (DoS) attacks.

Requesting New Services

  • Customers may request new services and service upgrades at any time by sending an email to indicating the requested services, contact information, and the desired completion date. In general, requests are processed on a first-come, first-served basis. ComTech maintains a small inventory of commodity equipment (generally desktop switching gear) to meet standard workflow requirements. In general, equipment requests will require that ComTech order equipment and supplies before scheduling installation.
  • A ComTech staff member will acknowledge a service request within 48 hours of posting to the ServiceNow system (or support email alias). ComTech will complete service requests on a first-come, first-served basis.

Registering IP Host Addresses and Names

LAN Administrators may register end systems by either sending a request via email to or requesting training to use the IP registration management client. After being certified by ComTech staff, LAN administrators will be granted access to add, change, and delete host information for zones (subnets) assigned to their department or group.

  • DNS updates are executed only at 7 am, 10 am, 1 pm, and 4 pm during regular business hours.
  • DHCP updates are executed hourly, 7 am – 8 pm, Monday-Friday.

Network Maintenance

The NC State network is dynamic, changing every day. Daily, nodes are added to the network, customers (and their subnets) move, and equipment is upgraded. While this change is a requirement, we plan, announce, and execute network maintenance to affect as few customers as possible and with minimal downtime. We categorize network changes as follows:

  • Installation: customer-initiated for adds, moves, and changes
  • Maintenance: ComTech-initiated for bug fixes, feature enhancements, maintaining network homogeneity
  • Emergency: ComTech-initiated for fixing network problems that involve serious network performance and/or availability degradation The regularly scheduled maintenance period for campus network services is 12 am to 6 am. All maintenance is coordinated with impacted customers before initiation. No maintenance affecting these services will be conducted without prior coordination with impacted customers. Routine maintenance will be announced at least 72 hours in advance.

All network maintenance will be announced via email and include the action, the reason for action, the planned start, the projected completion time, and affected customers. Network maintenance alerts are emailed to netadm and netinfo lists. These lists include LAN administrators and other students, faculty, and staff who wish to be notified of planned maintenance. In addition, all network maintenance will be announced via ServiceNow.

Customer Satisfaction

  • Customers dissatisfied with their level of service should immediately report any issues to the network manager and schedule a face-to-face meeting. Issues unresolved with the network operations manager should be escalated as necessary.
  • Customer feedback will ensure that we continue to deliver services required by our customers and at a level expected by our customers. The ComTech Director hosts periodic (at least semi-annually) update meetings to inform customers of network architecture plans and developments. These meetings also serve as a forum for customer feedback.