Industry news

RISC OS on youtube

The Iconbar - Sat, 01/26/2019 - 10:14
The video sharing site youtube is always an interesting place to find tutorials and see what other people are up to. There are some nice tutorials on how to update your RaspberryPi software, requests for help and people showing off their systems. There is plenty going on - what is your favourite link?

Latest RISC OS content on youtube can be from here.

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Categories: RISC OS

New - NetScaler Gateway (Maintenance Phase) 11.0 Build 72.16/72.17

Netscaler Gateway downloads - Wed, 01/23/2019 - 22:00
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - NetScaler Gateway 10.5 Build 69.3/69.5

Netscaler Gateway downloads - Wed, 01/23/2019 - 22:00
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - NetScaler Gateway (Maintenance Phase) 11.1 Build 60.13/60.14

Netscaler Gateway downloads - Wed, 01/23/2019 - 22:00
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - NetScaler Gateway (Maintenance Phase) 11.0 Build 72.16/72.17

Netscaler Gateway downloads - Wed, 01/23/2019 - 22:00
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - NetScaler Gateway 10.5 Build 69.3/69.5

Netscaler Gateway downloads - Wed, 01/23/2019 - 22:00
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - NetScaler Gateway (Maintenance Phase) 11.1 Build 60.13/60.14

Netscaler Gateway downloads - Wed, 01/23/2019 - 22:00
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - Latest EPA Libraries

Netscaler Gateway downloads - Wed, 01/23/2019 - 18:30
New downloads are available for Citrix Gateway
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New - NetScaler Gateway (Maintenance Phase) 12.0 Build 60.9/60.10

Netscaler Gateway downloads - Wed, 01/23/2019 - 18:30
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - Citrix Gateway (Feature Phase) 12.1 Build 50.28/50.31

Netscaler Gateway downloads - Wed, 01/23/2019 - 18:30
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - NetScaler Gateway (Maintenance Phase) 12.0 Build 60.9/60.10

Netscaler Gateway downloads - Wed, 01/23/2019 - 18:30
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - Citrix Gateway (Feature Phase) 12.1 Build 50.28/50.31

Netscaler Gateway downloads - Wed, 01/23/2019 - 18:30
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

New - Latest EPA Libraries

Netscaler Gateway downloads - Wed, 01/23/2019 - 18:30
New downloads are available for Citrix Gateway
Categories: Citrix, Commercial, Downloads

Modern Multi-Process Browser Architecture

Helge Klein - Tue, 01/22/2019 - 17:26
Contents

An architecture overview of current browsers on Windows: Chrome, Firefox and Internet Explorer.

In case you are wondering: I did not include Edge because it is currently being transitioned to the Chromium rendering engine, which might change a few things. I did include Internet Explorer because it is still the default browser in many enterprises.

Looking for a way to monitor web app performance? Take a look at uberAgent, our user experience & application performance monitoring product.

Chrome Architecture

Chrome was the first browser with a multi-process architecture. Put simply, it encapsulates all logical functions in separate processes. More specifically:

  • One main (browser) process
  • One GPU process
  • Each tab: dedicated process
  • Each extension: dedicated process

Chrome is the only browser with a useful task manager. It can be opened with the keyboard shortcut SHIFT+ESC. As you can see below, Task Manager lists all active Chrome processes with their designated functions. For each process, it shows CPU, network and memory resource usage. It also indicates whether frames are hosted in their page’s process or in dedicated processes (more on that below). Finally, Task Manager shows the Windows OS process ID, which makes it possible to correlate data with other system information tools.

Frames and Site Isolation

Frames share a process with their page if the frame and the page are from the same site (based on the URL).

Starting with Chrome 67, frames from different sites are put into different processes. This is called site isolation and aims to mitigate certain types of attacks. Chrome’s Process Internals page (chrome://process-internals/) lists the current status of each frame.

IE Architecture

IE’s multi-process architecture was introduced with IE8. It makes use of two types of processes:

  • One main (frame) process
  • Zero or multiple tab processes

Note the zero above. Depending on configuration, IE may be limited to just one process – in which case a bug in any component or add-on crashes all opened tabs. Keep in mind that IE add-ons are binary Win32 DLLs that are loaded into the tab process(es). A crash in an add-on also crashes the tab process(es) that host it. This is not the case with modern browsers (i.e., all other browsers), where extensions are basically web apps, built with JavaScript and HTML.

IE Tab Process Count

By default, the number of tab processes is auto-managed depending on the amount of RAM. This can be overridden by setting the TabProcGrowth registry value. It can either be a number (REG_DWORD) or a string (REG_SZ) – which is rather unusual.

A Microsoft blog post explains the TabProcGrowth value. It boils down to this:

Value Type Description 0 REG_DWORD single process for frame+tabs no matter what 1 REG_DWORD single process for frame+tabs per bitness (important for 32-bit add-ons on 64-bit machines) >1 REG_DWORD sets the maximum number of tab processes small REG_SZ max. 5 tabs per session medium REG_SZ max. 9 tabs per session large REG_SZ max. 16 tabs per session

Some notes and caveats:

Firefox Architecture

Historically, Firefox has been a single-process browser. As it turned out, running the browser UI plus the HTML rendering and JavaScript for all tabs in a single process is a bad idea. It easily freezes the UI, and it might not be optimal from a security point of view, either.

Mozilla started project Electrolysis as a gradual move to a multi-process architecture. This took 9 versions, from Firefox 48 to 56. The current architecture looks like this:

  • One main process
  • One GPU process
  • One extension process
  • Up to 4 content (tab) processes

The current default of 4 content processes might be changed in future versions. At this point, it can be increased to a maximum value of 7 content processes. Work is underway to encapsulate extensions in dedicate processes.

Summary

Browsers are evolving quickly – except for IE, of course. Microsoft is focusing on Edge. To be very clear: IE will not get any new features. It’s security updates only for the former world’s most popular browser who once had a market share of approximately 95% (in 2003).

It seems there is no way around the multi-process type of architecture. Benefits include increased stability and security. On the downside, we have an increased overhead.

The post Modern Multi-Process Browser Architecture appeared first on Helge Klein.

What’s on the Edge?

Theresa Miller - Tue, 01/22/2019 - 06:54

This year many organizations will kick off edge projects. Since this is a hot space, the terms and content you come across may seem contradictory and confusing. What are the terms you’ll need to know to get started with Edge Computing? Defining Edge Computing It’s always good to define terms, so when you’re discussing projects […]

The post What’s on the Edge? appeared first on 24x7ITConnection.

Office 365 Basics: Office 365 New User and Exchange Online Mailbox

Theresa Miller - Tue, 01/22/2019 - 06:30

While Office 365 has been out for some time, the interface is always changing.  We also need to start somewhere with knowledge and so what you will find is that I will be doing a series of posts called Office 365 Basics.  The goal is to start at the beginning to create a full understanding […]

The post Office 365 Basics: Office 365 New User and Exchange Online Mailbox appeared first on 24x7ITConnection.

David Pilling Treasure Trove

The Iconbar - Fri, 01/18/2019 - 07:02
If you are looking to learn about software, there is a treasure trove of source code and resources available on the Internet.

One of the more interesting resources is from David Pilling. He is something of a RISC OS legend (being behind OvationPro and many critical tools for RISC OS). His website lists his software and also includes several free utilities.

There is also an interesting section for 'retired' software here. Rather than just let the packages disappear, the source code is now available for all the ArcFax, Panorama, SparkFS and many other former commercial applications. Enjoy digging....

David Pilling website

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Categories: RISC OS

Bluetooth Audio Quality & aptX on Windows 10

Helge Klein - Tue, 01/15/2019 - 19:43

Bluetooth is a flexible standard. It defines various profiles that operate on top of the Bluetooth networking protocol stack and implement specific services, such as hands-free communications. Bluetooth devices each support a small subset of profiles, typically only one or two, according to their designated function.

Bluetooth headphones and speakers implement the advanced audio distribution profile (A2DP). The A2DP profile transports encoded audio streams from one device to another. To guarantee compatibility between devices, any device implementing the A2DP profile needs to offer a common codec, SBC. However, A2DP supports additional codecs that may increase audio quality or reduce latency compared to SBC. One of those optional codecs is aptX. In this article, I am looking at aptX benefits and I am describing how to get aptX on Windows 10.

What is aptX?

aptX is an alternative codec for the Bluetooth A2DP protocol. It comes in multiple flavors:

  • aptX
  • aptX LL (low latency)
  • aptX HD
Is aptX better than SBC?

Qualcomm, who acquired the aptX company CSR in 2015, claims that aptX offers “superior audio”. Figuring out whether that is actually true is harder than expected. Let’s break this quality question down into two different aspects: fidelity and latency.

Audio Fidelity

As this overview shows, the technical specifications of the base aptX code are similar to that of SBC. Specifically, the maximum bitrate of 352 kb/s is not much higher than SBC’s 320-345 kb/s (SBC depending on implementation).

The bitrate by itself does not tell us anything about a codec’s fidelity, however. Different codecs can be very different in encoding efficiency, as are H.264 and its successor H.265 for video (the latter only needs about half as many bits for the same visual quality). Fidelity can only be determined by double-blind listening tests. Unfortunately, nobody seems to have performed such listening tests in a scientific, reproducible manner (at least I could not find any information). Please let me know by commenting below if you know of any publications.

Another aspect influencing fidelity is that implementations do not always use a codec’s maximum bitrate. SBC, for example, comes with three quality modes, low (201 kb/s), middle (229 kb/s) and high (328 kb/s). Devices may select lower-quality modes to favor a stable connection over sound quality (example: these Sony headphones).

Audio Latency

When watching a video, you do not want the audio to lag behind. In other words: the audio latency should ideally be small enough to not be noticeable. Unfortunately, that is often not the case.

Bluetooth audio introduces significant latency, the exact amount of which depends on the codec as well as its implementations in the sending and receiving devices. Most Bluetooth headphone reviews do not include latency measurements, with the notable exception of rtings.com. They even have a list with latencies for all the headphones they ever tested. Plain aptX seems to be slightly better than SBC, but only aptX LL seems to be good enough to not be noticeable.

While, however, the number of devices supporting base aptX is steadily growing, support for aptX LL is still extremely rare (see rtings.com or bluetoothcheck.com).

Audio Quality Summary

There do not seem to be any objective comparisons between the aptX variants and SBC. From my experience it should be safe to say the following:

  • SBC offers pretty good fidelity at maximum bitrate.
  • aptX might be slightly better than SBC at maximum bitrate.
  • Both SBC and aptX introduce significant latency in the range of 150-200 ms.
  • aptX LL drastically reduces latency but is only supported by a handful of devices.
aptX on Windows 10 OS Support

If Microsoft wanted to hide this piece of information, they could not be doing a better job. A single page on microsoft.com mentions aptX. Apparently, Windows 10 has supported the aptX codec since the first release (1507). According to this Reddit thread, Windows 10 aptX support does not require any drivers in addition to what is part of the OS. I am mentioning that because numerous forum posts state you need to install special drivers. That does not seem to be true.

As for aptX HD or aptX LL (low latency): those codecs do not seem to be supported. If you would like to have them in Windows – especially aptX LL would be great when watching video – make sure to vote for this item in Feedback Hub: please add aptX Low Latency codec support to the Bluetooth A2DP driver.

For a list of supported Bluetooth versions and profiles see this page.

External USB Adapter

The Avantree Audicast is a flexible Bluetooth transmitter that can be connected to a PC (via USB) or a TV (via optical input or headphone jack). The Audicast has several neat features:

  • Support for aptX LL (low latency) in addition to regular aptX and, of course, SBC
  • LEDs indicate which codec is being used
  • Two receiving headphones can be connected
  • Small and light
  • No additional power source except for USB required
  • All cables are included

Please note that when connected to a PC, the Audicast does not work as a generic Bluetooth adapter (in which case the OS drivers would be used). Instead, it registers as a USB audio device. No drivers are required.

Which Codec and Bitrate are Being Used?

Amazingly, Windows does not provide any tool or API for monitoring the codec used by A2DP. Whether it is SBC, aptX or something different – users are left completely in the dark. To help change that and encourage Microsoft to provide more visibility, please vote for please let users see what Bluetooth A2DP codec is used.

For the sake of completeness I sent several hours capturing and analysing ETW logs as indicated at the following source, but none of the generated logs seemed to indicate the A2DP codec being used.

The post Bluetooth Audio Quality & aptX on Windows 10 appeared first on Helge Klein.

WEM 1811 UPDATE AVAILABLE

Wag the real - Alain Assaf blog - Tue, 01/15/2019 - 17:11
Intro Another season, another WEM version. The version numbering system in now in line with other newly released Citrix products. This version is 1811. You can now download the new version here (requires Platinum licenses and login to Citrix.com). I’ve provided the release notes below. I also have it on good authority that Citrix added […]
Categories: , Citrix, Virtualisation

Cool New Windows 2019 Features

Theresa Miller - Tue, 01/15/2019 - 06:30

After a rocky start in October due to a bad Windows Update that impacted the brand new Windows 2019 platform, Windows 2019 is available and being deployed. With every new Windows version comes a host of new features and functionality. Let’s take a look at some of the coolest new features in Windows 2019, broken […]

The post Cool New Windows 2019 Features appeared first on 24x7ITConnection.

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