Internet Service Disclosure

Network Practices

Congestion Management Policy

CenturyLink monitors and proactively reinforces our network with additional capacity in areas where growth trends identify a need. If network congestion occurs, CenturyLink employs various techniques to ensure a positive customer experience and fair distribution of network resources.
 

Currently, based on our experience, if CenturyLink customers encounter any congestion, it is typically during the hours of peak usage — between 7 p.m. and 11 p.m. local time. During peak hours, the majority of our residential customers are using the Internet simultaneously, giving rise to a greater potential for congestion. Peak usage will vary due to extraordinary conditions such as pandemics, weather events and/or national emergencies.
 

When network congestion is identified, CenturyLink uses various techniques to create a good customer experience. Our network management techniques include preventing virus/spam delivery to customer email accounts. We also reinforce our network with additional capacity in areas where congestion is identified or as part of standard network engineering design plans. In some cases, we may limit the number of customers that can be served on a particular network node or, in very rare cases, we may need to downgrade the service available to existing customers until additional capacity can be added. 

CenturyLink Excessive Use Policy

The CenturyLink Excessive Use Policy (EUP) uses a 1.0 terabyte (TB) monthly data usage limit. This limit applies to all uploaded and downloaded data for all residential CenturyLink High Speed Internet (HSI) customers except for those excluded below.  Of the millions of CenturyLink HSI customers, very small fractions exceed the data usage limit provided with their monthly HSI plan.

CenturyLink is committed to providing an optimal Internet experience for every customer we serve. It is for this reason that CenturyLink places data usage limits on residential plans. The data usage limit applies to residential HSI. It does not apply to business HSI.  Residential fiber internet plans are also not subject to data usage limits.  Any residential customer receiving discounted HSI service under a program to promote broadband adoption in low-income households is also not subject to the data usage limit.  Additionally, any customer purchasing Simply Unlimited Internet is not subject to the data usage limit.
 

CenturyLink does not currently charge customers a fee for excessive data usage. CenturyLink will weigh variables such as network health, congestion, and the availability of customer usage data as factors when enforcing this policy. Customers who have exceeded their monthly data usage limit and are subject to EUP enforcement will be notified by CenturyLink via web notification and/or written communication.
 

Customers who are subject to EUP enforcement are given options to reduce their usage, subscribe to a higher-speed residential HSI plan, or migrate to an alternate HSI service that is exempt from usage limits. Our EUP is application neutral; it only considers the total usage (bytes transferred) over a defined period of time independent of protocols, applications, or the content that is generating the excessive usage.
 

Customers who repeatedly exceed the EUP usage limit, and interfere with other customers' use of HSI service, are subject to the CenturyLink HSI terms of service.
 

For additional detail about the EUP, view the questions and answers.
 

The links CenturyLink and other networks use to exchange traffic may also become congested at times. CenturyLink devotes considerable resources to maintaining adequate traffic exchange arrangements with these other networks and has entered into commercially negotiated agreements to exchange traffic with them on mutually agreeable terms wherever possible. Consistent with its agreements with those other networks and its long-standing practices, CenturyLink will work to establish or expand the connections between its network and other networks on mutually agreeable terms when needed. But, sometimes this is not possible due to circumstances beyond CenturyLink's control. For example, in some instances, other networks refuse to make adequate arrangements. In other instances where adequate arrangements are in place, some edge providers or their intermediaries (other networks) choose to route traffic in ways that result in congestion when there are other choices. If CenturyLink is unable to reach agreement on the terms of its interconnection or network expansion with these other networks, or if some of these other circumstances occur, it could affect a customer's ability to upload or download data via Internet endpoints connected to those networks. CenturyLink cannot guarantee that it will be able to establish or expand the connections between its network and other networks, or that subscribers will be able to upload data to or download data from Internet end points connected to other networks at any particular speed.

Application-Specific and/or User-Specific Policy

CenturyLink High-Speed Internet customers receive full access to all the lawful content, services, and applications that the Internet has to offer.
 

As described more fully below, CenturyLink deploys Type of Service (ToS) and Differentiated Service (DiffServe) capabilities at the customer modem and in limited network equipment deployed across the CenturyLink High-Speed Internet network for the CenturyLink Digital Home Phone service (a non-BIA or specialized service). The network equipment enabled with this capability will honor ToS and DiffServe settings of any third-party network consistent with the National Standards recommendations described in the Internet Engineering Task Force (IETF) RFC 1349 and RFC 2474.
 

CenturyLink does not otherwise block, prioritize, or degrade any Internet sourced or destined traffic based on application, source, destination, protocol, or port unless it does so in connection with a security practice described in the security policy section below.
 

CenturyLink also deploys certain user-specific policies (i.e. practices that are applied to traffic associated with a particular user or user group). Currently, these are limited to practices described above and the security practices described in the security policy section below.

Device Attachment Policy

Customers have the flexibility of attaching any modem of their choice to their CenturyLink High-Speed Internet service provided that the modem supports the technology on which the customer is provisioned. CenturyLink will not support any modem-related issues for customers that attach a non-certified modem. See a list of CenturyLink compatible modems. Customers who choose to attach a modem approved by CenturyLink may contact our High-Speed Internet Technical Support Chat.
 

Customers are encouraged to check the firmware in their modems to ensure that the latest version of firmware is downloaded. See guidelines on how to upgrade your modem’s firmware.

CenturyLink customers may attach devices of their choice to the modem they select. Any attached devices must be used in a manner consistent with our Terms of Service and Acceptable Use Policy.
 

Customers in areas where CenturyLink provides wireless hotspots can connect wirelessly using any device equipped with IEEE 802.11 protocol.

Security Policy

CenturyLink engineers are dedicated to managing our network to ensure that all customers receive the most secure online experience. We use industry-leading security practices to manage our network, provide services to our customers, and ensure compliance with our Acceptable Use Policy and the terms of our High-Speed Internet agreement. These tools and practices may change from time to time to keep up with the new and innovative ways that customers use the network and to keep up with changing network technologies.
 

When malicious behavior is identified, CenturyLink engineers employ various techniques to help provide a positive customer experience. Our security management techniques include ensuring that customer systems are not propagating viruses, distributing spam email, or engaging in other malicious behavior. For example, we use industry best practices to prevent virus/spam delivery to customer email accounts. We provide anti-virus and anti-malware applications at no additional charge to our High-Speed Internet customers. We also automatically detect and mitigate DoS (Denial of Service) attacks for our High-Speed Internet customers. We block malicious sites and phishing sites to prevent fraud against our customers and to prevent our customers from getting infected via DNS (Domain Name Service) blackholing and Internet Protocol (IP) address blackholing.
 

We reserve the right at any time to take action to protect the integrity and normal operation of our networks and to safeguard our customers from Internet threats, including fraud and other forms of abuse. Such actions may include, but are not limited to, blocking, redirecting, or rate-limiting traffic using specific protocols, delivered over specific protocol ports, or destined for particular domain names or IP addresses associated with known malicious activity.
 

Specific security practices deployed by CenturyLink may include but are not limited to:

IP Spoofing Prevention

The basic protocol for sending data over the Internet network and many other computer networks is Internet Protocol (IP). The header of each IP packet contains, among other things, the numerical source and destination address of the packet. The source address is normally the address that the packet was sent from. By forging the header so it contains a different address, an attacker can make it appear that the packet was sent by a different machine. The machine that receives spoofed packets will send a response back to the forged source address, which means that this technique is mainly used when the attacker does not care about the response or the attacker has some way of guessing the response.
 

CenturyLink applies security measures to prevent an attacker within the network f