Measured components

This page describes the components measured by Keynote agents.

Transaction Perspective and Application Perspective components

The following components are measured by the Keynote Transaction Perspective (TxP) and Application Perspective (ApP) agents.

Network components

The components listed in the table below are referred to as “Network” components. To measure them, Keynote performs API interception of the WinInet library. (The WinInet library is used by Internet Explorer to interact with the Web. The calls to the relevant APIs are intercepted and the relevant parameters are logged.)

Note that not all components are always available for each page. For example, DNS Lookup will be reported only when the agent actually performs a DNS resolution; otherwise, the DNS Lookup value will be zero.

</tr></table> ### User experience components (Transaction Perspective only) In addition to the network components listed in the table above, there are additional components referred to as "User" components are reported by Transaction Perspective agents (not Application Perspective agents). These User components are not included in the Transaction Page graph in MyKeynote, but are included in the Summary data table beneath the graph, as well as being available in MyKeynote raw data downloads and Data Feed data dumps. The User components are obtained by monitoring status information reported by the Internet Explorer browser, not the WinInet library. The User Experience components are listed below:
Total Measurement Time Also referred to as Network Time or Total Time. The total time of all network traffic for a transaction measured by the Keynote agent—This is the total time needed to download a Web page from the network’s point of view. It starts from the beginning of the base file’s DNS lookup, and it ends when the last packet of the last page element has been delivered by WinInet to Internet Explorer for processing. It does not include any times during which no page element activity is taking place.
Estimated Cache Time This component is calculated by estimating what the network performance of the transaction WOULD be if the objects that can be cached were cached.
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DNS Lookup </td>

Time required for the DNS resolver to resolve the IP address of the host—The time will appear if actual resolution occurred, otherwise it will be zero.
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Initial Connection Time to open a TCP/IP connection
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SSL Time required to establish the SSL session—If the protocol is not SSL, the value of SSL will be zero.
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Redirection Total time spent in redirection—If no redirections are required, the value is zero. (This refers to server-side redirections, not client-side meta-refresh redirections.)
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Request Time Time required to send the request
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First Byte Download Time between the end of the request and time of arrival of the first packet of the response
Note that the term packet is used in the context of WinInet, that is, packets of data that WinInet retrieves. In most cases these are equivalent to TCP/IP packets.
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Base Page Download Sum of download time of all packets of the base html page, excluding the first packet
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Client Time Total time spent by the agent fetching the resource, excluding the time spent for interaction with the network
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Content Download Time to download all page elements other than the base page
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Object Count Number of page elements downloaded
Custom Component 1-3 Up to three custom measurement components can be created in transaction scripts.
</tr></table> Because Network components and User components are determined using different methods, it is not possible to directly map the two types of components to each other. {:#anchor_browser} ### Browser events Transaction Perspective measurements made with Internet Explorer 11 (along with Chrome 36 and Firefox 31) include the following set of components: #### Browser counts

User Experience Time </td>

(Formerly known as User Time.) The total time elapsed from when the browser started navigating to the page until the browser finished loading the page contents
IE Paint Start Time How long the measurement was running when the browser started displaying the current page
Time to Full Screen This is a special custom component that indicates the time for a page to appear by showing when a specified page element begins to download. 
Time to Interactive Page This is an approximation for when the page becomes fully interactive for the user. This corresponds to when the browser finishes processing the onload event.This is the loadEventEnd attribute of the Navigation Timing specification.
Total Network Time Total time of all network traffic for the page
Total Bytes Downloaded Total number of bytes that were downloaded from the web server
Throughput The average rate at which data was downloaded from the web server (Total bytes downloaded/Total network time)
Total Objects Downloaded The number of page elements downloaded
Cookie Count The total number of received third-party cookies for all pages in the transaction
If no cookies are received the value is NULL. Includes all types of cookies supported by the engine: HTTP cookies, Flash cookies, etc.
Domain Count The number of unique domain  resolutions (DNS requests) in the transaction
If the metric is not reported, the value is NULL. The value is the sum of all domain resolutions for all transaction pages.
Connection Count The number of unique TCP connections established in the transaction
If the metric is not reported, the value is NULL. The value is the sum of unique TCP connections for all transaction pages.
Browser Error Count The number of JavaScript execution errors reported by the browser, for individual transaction pages, or for all pages (Only used for trending.)
#### Durations
Unload How long the browser took to unload the previous page—This is the elapsed time between Unload Start and Unload End.
DOM Content Loaded How long the browser took to process the DOMContentLoaded event—This is the elapsed time between DOM Content Loaded Start and DOM Content Loaded End.
Load How long the browser took to process the onLoad event—This is the elapsed time between Load Event Start and Load Event End.
#### Times
Unload Start This is how long the measurement was running when the browser started unloading the previous page. This is the unloadEventStart attribute of the Navigation Timing specification.
Unload End This is how long the measurement was running when the browser finished unloading the previous page. This is the unloadEventEnd attribute of the Navigation Timing specification.
DOM Loading This is how long the measurement was running when the browser started processing the DOM for the current page. This is the domLoading attribute of the Navigation Timing specification.
First Paint (IE only) This is how long the measurement was running when the browser started displaying the current page. This information is only available from agents using Internet Explorer.
Interactive Page This is how long the measurement was running when the user could start to interact with the current page in the browser. This is the domInteractive attribute of the Navigation Timing specification.
DOM Content Loaded Start This is how long the measurement was running when the browser started processing the DOMContentLoaded event for the current page. This is the domContentLoadedEventStart attribute of the Navigation Timing specification.
DOM Content Loaded End This is how long the measurement was running when the browser finished processing the DOMContentLoaded event for the current page. This is the domContentLoadedEventEnd attribute of the Navigation Timing specification.
DOM Complete This is how long the measurement was running when the browser finished processing the DOM for the current page. This is the domComplete attribute of the Navigation Timing specification.
Load Event Start This is how long the measurement was running when the browser started processing the onLoad event for the current page. This is the loadEventStart attribute of the Navigation Timing specification.
Load Event End This is how long the measurement was running when the browser finished processing the onLoad event for the current page. This is the loadEventEnd attribute of the Navigation Timing specification.
## FTP service components The following components are measured by the Keynote FTP Service agents.
DNS Lookup Time required for the FTP client to resolve the IP address of the FTP server—The measurement is performed only on an “open” FTP call, since the others will not need a DNS resolution.
Initial Connection The time taken by the client to establish the TCP/IP connection—Valid for “Open”, “Put” and “Get” commands.
SSL Not applicable to FTP.
Redirection Not applicable to FTP.
Request Time Not applicable to FTP.
First Byte Download The time taken for the first packet of response from server—Valid for all FTP commands.
Base Page Download The time taken from the First Byte Download time to the end of the download from the FTP server—Valid for “Open” and “Get” commands.
Client Time Not applicable to FTP.
Bytes Download This is the total number of bytes received on both the Data and Control connections for the FTP command.
## Mobile Device Perspective components These components may be reported in Mobile Device Perspective measurements. (Specific components depend on type of MDP account.)
Bandwidth Bandwidth is the average data transfer rate measured in kilobits per seconds, of all data transferred from the first byte of a file to the final byte of the file.
Max Latency Max Latency is used both to set the maximum run time of certain types of tests and more generally the cutoff point at which a successful test becomes an error.  This happens when the sum of all measured time segments is greater than the max latency value.
Signal Level This indicates the signal strength as displayed on most wireless devices. The Signal Level is the number of signal bars displayed out of the total. For example, if a phone has 5 bars, full strength is a Signal Level of 5 out of 5.
## Mobile Web Perspective components
DNS Lookup Time required for the DNS resolver to resolve the IP address of the host—The time will appear if actual resolution occurred, otherwise it will be zero.
Initial Connection Time to open a TCP/IP connection
WAP Connection Not currently used; always zero (0).
SSL Time required to establish the SSL session, if applicable—If the protocol is not SSL, the value of SSL will be zero.
Redirection Total time spent in redirection, if any—If no redirections are required, the value is zero.
Request Time Time required to send the request
First Byte Download Time between the end of the request and time of arrival of the first packet of the response
Note that the term packet is used in the context of WinInet, that is, packets of data that WinInet retrieves. In most cases these are equivalent to TCP/IP packets.
Base Page Download Sum of download time of all packets of the base html page, excluding the first packet
Content Download Time to download all page elements other than the base page
Client Time Total time spent by the agent fetching the resource, excluding the time spent for interaction with the network
## Streaming Perspective
Availability The ratio of successful checks to total checks performed on a stream
A check is considered successful if playback begins within 60 seconds of the request. (For example, a stream still buffering by the end of the check is considered a failure.)
Total Frustration Time Connect Time + Buffer Time + ReBuffer Time. Frustration time is made up of these three non-viewing activities. The number of Rebuffer events is also recorded.
Time Each of our streaming agent players have a default buffer of 5 seconds. This is 5 seconds of viewable/audible time once the player starts playing the stream. The buffering time is the time it takes to fill that 5 second buffer.
DNS Lookup (sometimes referred to as Resolve Time) Time required for the DNS resolver to resolve the IP address of the host—The time will appear if actual resolution occurred, otherwise it will be zero.
Connect Time The time required to establish a network connection to the streaming server before any streaming protocol requests are made
Buffer Time Time between the first packet’s arrival and the beginning of playback
Rebuffer Time Time taken by one or more interruptions, after playback has begun, for further buffering
Framerate Frames per second—a measure of the rate at which pictures are shown for a motion video image
ABR - Average Bitrate Average bitrate is based only on checks that managed to connect; failed checks are ignored for the purpose of calculating these quantities.
Packets Lost Number of packets not received
Packets Received Number of packets received
Total Packets Packets lost plus packets received
Playback Time Actual time playing the stream—The total time given for a measurement is 60 second by default, so we would expect a good measurement to show near 60 seconds of playback time.
StreamQ A metric for quickly summarizing the effects of connecting, buffering and possible rebuffer events The following equations and definitions demonstrate how StreamQ™ is assigned to each check:
  • Frustration Time + Play Time = Check Time. Every second of Check Time is either spent viewing/listening to content or waiting for the content to arrive.
  • Frustration Time = Connect Time + Buffer Time + ReBuffer Time. Frustration time is made up of these three non-viewing activities. The number of Rebuffer events is also recorded.
  • Connect Time = Amount of time elapsed between the initial request for data by the media player and the start of buffering. This time includes DNS lookup and resolution, Metafile actions and resolution, server/player handshakes and the transport of the first byte of data to the player.
  • Buffer Time = Amount of time used to build up the initial buffer of data for the stream, based on player default settings.
  • Rebuffer Time = Amount of time required to refill the buffer for all rebuffer events. This time represents interruptions of the viewing/listening experience. To provide a further penalty for rebuffering, 2 seconds are added to the Frustration Time for each rebuffer event.
Below is a “time-profile diagram” that shows a typical successful check. The connection took 1.2 seconds to complete, followed by 3.4 seconds of buffering. The remainder of the 60 second check (55.4 seconds) was spent playing. The total Frustration time is 4.6 seconds which translates to an A+ (since it is under 6 seconds). This time-profile diagram shows a stream that suffered from rebuffering during playback. Each rebuffer event adds a 2 second penalty to the overall Frustration time, in addition to the actual length of the rebuffering.