How does AT&T manage congestion with respect to its mass market broadband internet access services?
AT&T strives to provide a high-quality internet experience for all of our customers. Because the internet consists of multiple interconnected networks and most internet end points (e.g., websites and other content providers) are not directly connected to the AT&T network, AT&T must connect to and exchange traffic with other networks to provide its subscribers the capability of uploading data to or downloading data from internet end points that are connected to those networks. To that end, AT&T has entered into commercially negotiated agreements to exchange traffic with those networks (and the networks with which those networks are connected) on mutually agreeable terms. The links AT&T and other networks use to exchange such traffic may become congested at times. Consistent with its agreements with those other networks and its long-standing practice, AT&T may establish or expand the connections between its network and other networks, but only on mutually agreeable terms. If AT&T is unable to reach agreement on terms of interconnection or network expansion with these other networks, it could affect customers’ ability to upload or download data to internet endpoints connected to those networks. AT&T does not guarantee that it will 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.
In addition, like the other networks that make up the internet, the AT&T network is a shared network, which means that the transmission links and other network resources used to provide broadband services are shared among AT&T’s subscribers, as well as among the various services offered by AT&T. Temporary congestion may occur when a large number of customers in a concentrated area access the network at the same time or when some customers consume a very large amount of network capacity during busy periods, such as at stadium events, during peak usage times, or during planned network maintenance.
AT&T invests billions of dollars annually to address potential congestion in its broadband networks. As is common in the industry, we use network management practices and other tools to manage network resources for the benefit of all of our broadband customers, especially during periods when network demand exceeds available network resources (also known as “congestion”). As you would expect, our network management practices and our service offerings have evolved over time to benefit our customers and take advantage of the billions we have spent to expand and augment our networks.
Congestion-based Data Management. One network management practice we use to manage our wireless network resources may affect customers with most AT&T post-paid and AT&T PREPAIDSM unlimited mobile data plans (“AT&T Unlimited Data Plans”). During periods of congestion, these customers may experience reduced data speeds and increased latency as compared to other customers using the same cell site (“Congestion-based Data Management”). Depending on the customer’s AT&T Unlimited Data Plan, they will either always experience Congestion-based Data Management or experience it only after they have used a set amount of data in a billing period as outlined in their AT&T Unlimited Data Plan (for example, 22GB or 50GB of data in a billing period). As always, even when subject to this congestion management practice, these customers have the comfort of knowing that, no matter how much data they use in a billing cycle, they will never be subject to overage charges and will pay a single monthly flat rate. That is our essential promise with the AT&T Unlimited Data Plans. Reduced speeds and increased latency may cause web sites to load more slowly or affect the performance of data-heavy activities such as video streaming or interactive gaming. Customers subject to Congestion-based Data Management will experience reduced speeds and increased latency only when they use data at a cell site experiencing network congestion at the same moment. As soon as the congestion at the cell site abates, or if the customer’s session migrates to an uncongested cell site, speeds and latency are not affected. In addition, this network management practice adjusts dynamically to address the amount of congestion, which can start and stop over a very short time period (often measured in fractions of a second), further minimizing any customer impact. Because the amount of congestion at a cell site can vary significantly, the performance impact for affected AT&T Unlimited Data Plan customers may also vary significantly, but such impact will last only as long as the site is congested.
For customers on plans subject to a data usage threshold for triggering the foregoing congestion management practice, we will notify them during each billing cycle when their usage reaches 75% of their threshold (so, for example, 16.5GB for plans with a 22GB threshold and 37.5GB for plans with a 50GB threshold) so they can adjust their usage to avoid network management practices that may result in slower data speeds.
Buffer Tuning. With the ever-increasing growth in smart phone and tablet usage on our wireless networks, and the growing prevalence of video downloads, AT&T has deployed a reasonable network management video optimization technique in our mobile data network. That technique delivers recorded video to the user's device in a "just in time" fashion (“Buffer Tuning”). Buffer Tuning only applies to internet browser traffic (HTTP, port 80) for recorded video downloads, regardless of the source (including AT&T branded or 3rd party content) and does not affect real-time streaming video. Without Buffer Tuning, video content may be completely delivered to the device and charged against the user's data plan regardless of whether it is viewed. With Buffer Tuning, a sufficient amount of video is delivered to the device so that the user can start viewing the video, and the remainder of the video is delivered just in time to the device as needed for uninterrupted viewing. This optimizes the user's data plan consumption. Additionally, this frees up network resources for all users. Buffer Tuning does not alter video content and should not directly introduce any adverse impact to the viewing experience.
Stream Saver. Another reasonable network management practice we use to more efficiently manage our wireless network resources is Stream Saver, which is a feature we offer on some of our wireless plans that include data. Stream Saver allows customers to watch more video over our wireless network while using less data by streaming content recognized as video content at Standard Definition quality, similar to DVD (about 480p, max 1.5 mbps). In instances where a content provider uses the same server name identification (SNI) or URL to deliver both streaming video and downloadable video, Stream Saver may treat the downloadable video and thereby affect the speed of the video download. Stream Saver applies only to recognized video content delivered over AT&T’s wireless network. If two or more tethered devices are watching video from the same source at the same time, we may identify it as a single video and slow the speeds collectively to a max of 1.5 Mbps, which may impair your ability to watch video on these tethered devices. You can pause video on all but one of the tethered devices, watch video from different sources, or turn off Stream Saver to resolve this issue. Once activated by AT&T on a customer’s account for plans that include Stream Saver, the customer can turn it off and back on at any time via the customer’s online account or by calling AT&T. More information is available here.
Does AT&T limit data usage? Does AT&T provide any tools to help customers monitor and control their data usage?
We have developed speed tiers for our wired and data plans for our mobile broadband internet access services so that our customers can choose from a variety of speed tiers or rate plans that best reflect their own usage levels, and the manner in which they intend to use their service. For example, some AT&T data plans designated for use only with a basic phone or smart phone may not be used with a LaptopConnect card, tablet, or stand-alone mobile hotspot device. However, customers wishing to use their service in such a manner, such as with a mobile hotspot device, may purchase other plans that permit such use. AT&T provides usage calculators, alerts, and other tools for our wired and mobile broadband internet access services to assist customers in estimating their anticipated usage levels. For more information, please click here (wired) and here (mobile). In addition, we send notices to customers of applicable usage thresholds for our tiered wired and mobile services. Many of AT&T’s Internet, Broadband, or Fiber plans for businesses have no data caps or data usage plans.
We have some post-paid mobile plans that provide customers allotments of high speed data they may share among different devices on the plan (for example, our AT&T 4GB plan and our now grandfathered Mobile Share class of plans), and some of our AT&T PREPAIDSM plans (not including AT&T Wireless Internet or Mobile Hotspot) provide an allotment of high speed data to the specific line. Once customers on these plans exceed their allotments of high speed data -- which includes the plan data, any available Rollover Data (if applicable), or other data allotments customers may have -- during a billing period, depending on their plan they can either continue to consume data at no extra charge, but at significantly lower speeds when connected to the cellular network, or they will automatically be charged an overage for an allotment of highspeed data (for example, $10 for 2GB for the AT&T 4GB plan). For customers on the former type of plan (those with no overage but significantly lower speeds after exhausting the monthly allotment of high-speed data) who use all available high speed data allotments in a billing cycle, the customer’s service over the cellular network will transmit data at a maximum of 128Kbps for the remainder of the billing cycle. Once speeds are limited like this, the customer’s connection over the cellular network should still allow viewing static web pages or checking email, but bandwidth-intensive activities such as audio and video streaming, picture and video messaging, and apps/services that use large amounts of data will be impacted and may not be fully functional. But, when the next billing cycle begins, the customer will once again have high speed data access. We will notify customers during each billing cycle when their data usage reaches either 75% or 90% of their monthly high-speed allotment (or at both intervals), and when they reach 100% of their monthly high speed data allotment so that they are aware of their amount of data usage and can make adjustments to avoid slower speeds or data overage charges. When connected to a Wi-Fi network, the customer’s speed will not be impacted nor will overages apply, if applicable. For information regarding these types of post-paid Mobility plans and Rollover Data, click here (and see the 4GB Plan tab), and for AT&T PREPAIDSM plans, click here.
Another way we help wireless customers manage their data usage is through the Stream Saver feature summarized above.
As a benefit to America’s military veterans, AT&T has partnered with the U.S. Department of Veterans Affairs (VA) to provide veterans subscribing to AT&T’s wireless services free, unlimited access to real-time video healthcare services through VA-approved telehealth applications, such as the VA’s Video Connect application. AT&T customers who are veterans can access and use such applications across AT&T’s wireless network without that usage counting against their plans’ data usage allowances. Providers of applications authorized by the VA to provide such access that are interested in partnering with AT&T to provide its subscribers free access to those applications may contact us to obtain information about how to do so. For more information on AT&T’s support for U.S. military veterans (and active military members), click here.
For those geographic areas that are not served by AT&T’s owned and operated mobile networks, we try to provide customers with data services through agreements with other carriers. The use of customers’ devices to access data over another carrier’s networks – both domestic and international – is called “off-net” or “roaming” usage. Our ability to make off-net or roaming services available to customers is based on a variety of dynamic factors, including business considerations, the terms of the agreements we have at any given time with other wireless carriers, and the network technology, frequency(ies) and functionality of those networks. We do not guarantee the availability, quality of coverage or speed for data services that are accessed using other carrier networks and we may reduce speeds to 2G speeds or suspend the data service available on these networks at any time without notice. We update our coverage maps regularly to show where we provide domestic off-net and international roaming services. To obtain the most recent coverage updates you may access the maps here.
How does AT&T handle alleged copyright infringement by subscribers to its broadband internet access services?
The AT&T Copyright Alert Program was established to respond to alleged copyright infringement activities using peer-to-peer file sharing and attempts to educate customers about the importance of protecting copyright and lawful use of content available over the internet. Under the program, content owners may notify AT&T of alleged copyright infringement based on the IP address of a user. AT&T then will attempt to identify a subscriber account based on that IP address and forward a copyright alert to the subscriber account, advising the account holder of the allegation and providing information about online copyright infringement. If a subscriber receives additional alerts, we may temporarily redirect the account holder’s broadband internet access service to a webpage where the account holder must review material on the importance of copyright and the lawful use of content available over the internet. Upon completion of this review, such redirection will be discontinued and the subscriber’s service will be restored to normal. After this stage, if a subscriber continues to receive additional alerts, then AT&T may take action consistent with Section 512(i) of the Digital Millennium Copyright Act, which may result in termination of the subscriber/accountholder’s broadband internet access service. Account holders’ personally identifiable information is protected throughout this process — AT&T will not provide such information to content owners unless required to do so by court order. For more information about AT&T’s Copyright Alert Program, please go to: https://copyright.att.net/home.
Does AT&T favor certain websites or internet applications by blocking, throttling, or modifying particular protocols on its broadband internet access service?
No, AT&T does not favor certain websites or internet applications by blocking or throttling lawful internet traffic on the basis of content, application, service, user, or use of nonharmful devices on its broadband internet access services. Nor do we modify particular protocols, protocol ports, or protocol fields in ways not prescribed by the protocol standards. However, in response to a specific security threat against our network or our customers, AT&T may occasionally need to limit the flow of traffic from certain locations or take other appropriate actions. In addition, we prevent the use of certain ports on our wired and Wi-Fi broadband internet access services to help protect our customers and network against malicious activity, as discussed below.
Our mobile broadband internet access service data plans may include different speeds, video streaming quality, and other options consumers can choose among so as to find the best fit for the manner in which they intend to use their service. For example, the AT&T Unlimited Elite plan allows users to stream video in High-Definition (up to 1080p), where available (streaming video services may transmit only lower quality video content) and when Stream Saver is turned off, while the AT&T Unlimited Starter plan allows for streaming Standard Definition (480p/DVD quality) video. Customers watching streaming video on a Smartphone or other small hand-held device likely will not notice a significant difference between High-Definition and Standard Definition video quality, while those watching streaming video on a tablet or other larger device may prefer High-Definition video quality. For more information about our mobile broadband internet access service data plans, please go to: https://www.att.com/plans/wireless.html
Does AT&T directly or indirectly favor some traffic over other traffic (such as through prioritization, resource reservation, or traffic shaping) in its provision of broadband Internet access service either (1) in exchange for consideration (monetary or otherwise) from a third party, or (2) to benefit an affiliate?
No, in its provision of broadband internet access services, AT&T does not directly or indirectly favor some traffic over other traffic in exchange for consideration from a third party or to benefit an affiliate, except to address the needs of emergency communications, law enforcement, public safety (including FirstNet), or national security authorities, consistent with or as permitted by applicable law. Additionally, AT&T offers a wide variety of services to its customers, including but not limited to Voice over Internet Protocol (VoIP), Internet Protocol (IP)-video, unified messaging, Voice over LTE (VoLTE), and enterprise networking. These services share AT&T’s network infrastructure and may rely on network practices to assign different levels of priority dynamically or statically. Use of these services may affect the availability of network resources for broadband internet access services, and thus the performance of that service. For example, your service may be interrupted, delayed, or otherwise limited in the event of a disaster or emergency, or during periods of congestion, to accommodate the needs of national security and emergency preparedness personnel.
What practices has AT&T adopted to manage network security?
AT&T takes the security of our customers and our network very seriously. We proactively monitor network activity to help guard against a wide range of security threats, including viruses, botnets, worms, distributed denial of service attacks, SPAM, and other harmful activity. We encourage customers to adopt their own security practices.
If we detect a security threat, we will typically attempt to isolate the threat and minimize the impact to network service. We may use a variety of security measures to protect the network, including blocking malicious or unlawful traffic, redirecting the flow of traffic over some portions of our network, or taking other actions to address the threat. For example, as described in more detail below, we block certain ports that transfer malicious or disruptive traffic (such as Ports 25, 135, 139, 445, and 1900). We attempt to limit actions to the specific portions of our network or customer base impacted by the security threat and only for as long as necessary to mitigate the threat.
AT&T may scan or analyze network addresses that are registered through AT&T, including addresses that may have been delegated to customers, and/or routes that originate from AT&T-provided networks to detect vulnerabilities that might be used to compromise AT&T or customer assets or might be used in attacks against others. In doing so, we seek to avoid disrupting network service to customers. We may use information derived from these activities to identify and address security issues or to notify customers of issues.
As noted above, AT&T blocks certain ports that transfer malicious or disruptive traffic to protect our customers and our network. Below is more information about port blocking that is currently in place. We may block additional ports in the future based upon threat assessments.