HLS Protocol
Enable HTTP Live Streaming (HLS) protocol : LOAD TEST supports the recording of a script using Media Streaming (HLS) protocol. HTTP Media Streaming (HLS) is an HTTP-based media streaming communications protocol, used to deliver the media content by breaking the overall stream into a sequence of small HTTP-based files. The client can choose from a range of alternative streams that play the same content while being encoded at various data rates, allowing the streaming session to adjust to the available data rate.
HTTP 2 Settings
Enable Server Push : This uses a secure challenge/response mechanism that prevents password capture or replay attacks over HTTP. However, the authentication is per connection and will only work with HTTP/1.1 persistent connections.
For this reason, it may not work through all HTTP proxies and can introduce large numbers of network roundtrips if connections are regularly closed by the web server.
By default, HTTP authentication is implemented using the selected version of NTLM i.e. NTLM2. If the user wants to disable the authentication then he/she can enable this check box.
Max Concurrent Streams from Server : This refers to maximum number of connections that can be established in parallel to a particular host.
Initial Window Size : Specify the initial window size. By default, it is 1024 MB.
Maximum Frame Size : Specify the maximum frame size. By default, it is 16 KB.
Header Table Size : Specify the header table size. By default, it is 4 KB.
HTTP/3 Connection Settings
Maximum Data Per Connection : It is the maximum amount of data that can be sent on the entire connection in Megabytes (MB).
All data sent on STREAM frames counts toward this limit. The sum of the final sizes on all streams (including streams in terminal states) MUST NOT exceed the value advertised by a receiver.
Maximum Window Size: This is applicable when auto tuning is enabled. It indicates maximum connection-level flow control window size in Megabytes (MB).
Handshake Timeout : It is the timeout for QUIC connection establishment in milliseconds (ms).
Initial Round Trip Time : Round-trip time (RTT) is the duration(ms) taken for a network request to go from a starting point to a destination and back again to the starting point. Initial_RTT is used when no RTT sample is available.
Delay Stream : It is the duration after which the client sends the first 1-RTT stream.
HTTP/3 Stream Settings
Maximum Data On Bidirectional Local : It is the flow control limit for Load Test initiated bidirectional streams which are used for HTTP requests and responses.
Maximum Data On Bi-Directional Remote : It is the flow control limit for server-initiated bidirectional streams.
Maximum Data Unidirectional : It is the stream-level flow control limit for unidirectional streams (control for settings and push streams).
Maximum Window Size : This is applicable when auto tuning is enabled. It indicates maximum stream-level flow control window size in Megabytes (MB).
Maximum streams unidirectional : It is the maximum number of unidirectional streams permitted by the remote endpoint. If it is absent or zero, the peer cannot open unidirectional streams until a MAX_STREAMS frame is sent.
Authentication
HTTP Authentication using NTLM : Specify the header table size. By default, it is 4 KB.
Kerberos Authentication : This is a computer network authentication protocol that works based on 'tickets' to allow nodes communicating over a non-secure network to prove their identity to one another in a secure manner. When enabled, Kerberos authentication is not implemented.
Maximum Connection(s) Per Virtual User Setting
Here, the user can specify maximum connections (server, proxy, and user) per virtual user setting. For browser settings, it is set by default.
Max Connection Per Server : Select the connection required in HTTP 1.0 and HTTP 1.1 servers respectively.
Max Connection Per Proxy : Select the connection required in HTTP 1.0 and HTTP 1.1 proxy servers respectively.
Max Connection Per User : Select the number of connections needed per user.
Network Cache Stats Settings
Network cache stats provide valuable insights into the handling of requests by the network cache (edge servers) such as requests served from the cache (hits) or from the origin (miss). Hits give good indication of how many requests are offloaded from Origin. By default, these stats are enabled. You can modify using following options:
Enable network caching stats for HTTP requests and Transaction NetCache Hits (pct) metrics: By selecting this option, you can access network cache stats metrics on the dashboard and observe the percentage of network cache hits from the transaction table.
Send Pragma header for getting cache status in the response headers: This is needed only when Akamai is used and response is not coming from server timing. Send following Akamai Pragma header to get cache status in the response:
Pragma: Akamai-x-cache-on, Akamai-x-cache-remote-on, and Akamai-x-check-cacheable.
Change transaction name if response is severed by Network Cache by adding suffix: Change the transaction name by appending a provided suffix when the response for a URL is served from the network cache. For instance, if the transaction is initially named "SearchProduct" and a request is served from the network cache, the transaction name will be modified to " SearchProduct_NetCache".

Network cache stats are available in "Network Cache Stats" Metric Group and Transaction NetCache Hits (Pct) metric is available in 'Transaction Stats' Metric Group. Transaction NetCache Hits (Pct) is also shown as one column in Transaction Details Screen and it is based on main URL only.

Network caching stats is based on following HTTP response headers:

  • X-Cache, X-Cache-Remote, xCacheRemoteL2, xCacheL2, and CF-Cache-Status
    • Hit - Value contains ‘Hit’ (e.g. X-Cache: TCP_HIT from a23-200-239-238.deploy.akamaitechnologies.com (AkamaiGHost/11.1.0-48589741) (-))
    • Miss: Value contains ‘Miss’ (e.g. X-Cache: TCP_MISS from a23-46-9-55.deploy.akamaitechnologies.com (AkamaiGHost/11.1.0-48589741) (-))
    • Others: Values does not have Hit or Miss
  • Server-Timing
    • Hit - Value contain ‘cdn-cache; desc=HIT’
    • Miss - Value contain ‘cdn-cache; desc=MISS’
Other Settings
Fail page if embedded URL of page fails : When enabled, the page status is set as 'failed' if embedded URL of a page fails.
Runtime Changeable No