Network Link Conditioner is a network utility tool provided by Apple that can simulate various network conditions and help us to develop better apps. If you ever received a bug report where user mentioned slow network connection the Network Link Conditioner will help you to reproduce that issue.
You will need to go to more downloads page on the Apple Developer portal to and search for appropriate Additional Tools for your Xcode version. This link will take you directly to those search results. Download the dmg file, open it, and inside Hardware folder you will find the file called Network Link Conditioner.prefPane.
Network Link Conditioner
Network Link Conditioner comes with a lot of presets that you can use like 3G, Edge, Very Bad Network, LTE, 100% Loss and more. They are great for testing your app on bad network conditions and in most cases you will not need to create custom presets (profiles).
Edge is a great preset to see how your app behaves on very slow networks. Very Bad Network preset is great when you want to test that you have connection to the Internet but that it is very unreliable.
The Network Link Conditioner on iOS and macOS enables you to test your app in networking conditions like your users might have while using your app. It allows you to simulate networking conditions like 3G, Edge or High Latency DNS.
The tool is called Network Link Conditioner. It is an awesome tool that allows you to simulate different network connections on your Mac, such as WiFi and 3G. You can even set your own custom network connections!
For some fun, I created a blank layout and a script that creates 1000 new records. I tested the performance of the script locally, and then using a server over the WAN under my normal network connection, Wifi, Average Case, 3G Good Connectivity, and 3G Lossy Network.
It would be great to have a simple way to test different network speeds at home. Years ago I made Throttle that is command-line interface for throttling network connections on your desktop computer for Mac and Linux. But I want to be able to do the same for my phones and tablets.
I previously covered using Network Link Conditioner to test how your app does in less-than-ideal network scenarios. One of the inconveniences of using it is in order to test your app on a device, you have to take the extra steps to configure a proxy on your computer that your device can connect to over a wi-fi connection. Well, not anymore. With iOS 6, Apple has given us Network Link Conditioner right on the device.
I read in a few places people saying Network Link Conditioner is supposed to work on localhost. However I never managed to get it working. It works for any of my external communications. If I use it and connect to another machine on my local network, it works.
Even though most parts of the world have access to the internet, all internet connections are not born alike. Even areas within the same country, city, town, or even street can vary. Any mobile app seeking to appeal to the largest possible number of users should be able to run reasonably at different network speeds.
In order to check how an app performs in slower internet connections, QAs need to simulate slow network speeds and put the app through various user actions. There are multiple ways to do this, as this article will demonstrate.
It's important to understand what using your app or site feels like when connectivity is poor or unreliable, and build accordingly. A range of tools can help you.Test with low bandwidth and high latency #An increasing proportion of people experience the web on mobile devices. Even at home, many people are abandoning fixed broadband for mobile.In this context, it's important to understand what using your app or site feels like when connectivity is poor or unreliable. A range of software tools can help you emulate and simulate low bandwidth and high latency.Emulate network throttling #When building or updating a site, you must ensure adequate performance in a variety of connectivity conditions. Several tools can help.Browser tools #Chrome DevTools lets you test your site with a variety of upload/download speeds and round-trip times, using presets or custom settings from the Network panel. See Get Started with Analyze Network Performance to learn the basics.
For iPhone, Network Link Conditioner can be used to simulate impaired network conditions (see above).Test from different locations and networks #Connectivity performance depends on server location as well as network type.WebPagetest is an online service that enables a set of performance tests to be run for your site using a variety of networks and host locations. For example, you can try out your site from a server in India on a 2G network, or over cable from a city in the US.
Software and hardware proxies enable you to emulate problematic mobile network conditions, such as bandwidth throttling, packet delay, and random packet loss. A shared proxy or impaired network can enable a team of developers to incorporate real-world network testing in their workflow.Facebook's Augmented Traffic Control (ATC) is a BSD-licensed set of applications that can be used to shape traffic and emulate impaired network conditions:
In the past, hacky methods using XHR have been used to test for intermittent connectivity, but service worker enables more reliable methods to set network timeouts. This can be achieved using Workbox with only a few lines of code:
Need to test your app on slow cellular connections? Bring on the iOS network link conditioner! As a best practice for mobile development, developers and testers should test network connected apps under lots of different network conditions on real mobile devices. The simulator can be great for some development activity, but a majority of your development and testing should be on a real device.
Mobile devices connect to the Internet via a wide range of connection types and speeds. Network unreliability is an expected condition on mobile. Our mobile devices push the paradigms of network connectivity into new space. So how do we test for these different conditions? Thankfully, Apple has included a network link conditioner right in iOS that helps to simulate different types of network connections right on a development device.
Test your app! With the link conditioner turned on, go test your app and see how it operates under different network conditions. Think about the areas of the app that make network requests and ensure that your app responds appropriately to time outs, data loss, etc.
It's useful to be able to test your fancy new single page application or progressive web app in different network conditions. On desktop you can do so by using network throttling on Chrome dev tools for example.
In a previous edition of Appium Pro, we sketched out some options for measuring various network metrics for your mobile apps. In this edition, we spin the situation around, and ask: how can we simulate specific network speeds or conditions, in order to then test some other aspect of our app's behavior? For example, we might want to know how long a certain user flow takes when they are on a 3G network vs an LTE network.
If we want to automate a real device with specific network conditions, then we either need to put the device physically into those conditions (geographical location, mobile network provider, mobile network speed, etc...), or simulate it by connecting the device via wifi to a router which has some network shaping software on it. In either case, it's not something that's easy to attempt "at home".
Virtual devices (like iOS simulators or Android emulators) are a different story, however! They share the same network as the virtual device host, which at least in the case of iOS is guaranteed to be a macOS machine. On macOS, which we assume we're using for this article, we have a few different ways to simulate a variety of network conditions for the entire system, which also ends up changing the network conditions for the iOS simulator or the Android emulator.
Apple actually provides a special Preference Pane that allows you to adjust the network speed of your computer. It's called the Network Link Conditioner, and you can download it following these instructions. When you've installed it, it looks like this:
Using this interface, you can manually select a certain network profile and toggle it off and on again. You can even, for example, select a profile which has 100% packet loss, meaning no network connectivity at all. This is useful to test your app's behavior in situations where the user loses connectivity, perhaps even in the middle of a user flow.
Here I've simply defined NET_SCRIPT to be the path to the network conditioning script, and also made sure to put my stopNetworkConditioning method in a finally block so that we guarantee it is reset even if we get an error during the actual test step execution. Feel free to check out the full code example on GitHub.
That's it! Again, we're dealing with a pretty limited scenario here, since this trick only works with virtual devices, and it also affects the system network speeds (so if you're trying to stream video while running your test, you may notice some unpleasant side effects). But it's a quick and easy way to see how your app behaves in a variety of network conditions, without needing any specialized proxy software or other services.
Monitoring can be started from anywhere in the code by simply calling NetworkMonitor.shared.startMonitoring(), though in most cases you'll want to initiate this process in the AppDelegate. Then, we can use NetworkMonitor.shared.isConnected to check the status of our network connection in real-time.
The behavior of modern iOS apps changes dramatically when the device's network connectivity fails - some screens might show a notice that the device lost connection, the application's caching behavior changes, or certain user-flows disappear completely. 2ff7e9595c
Comments