WhatsApp is one of the most popular messaging apps in the world, with over 2 billion users globally. When sending a message on WhatsApp, users can see one tick, two ticks, or two blue ticks to indicate the delivery status of their message. The one tick indicates the message has been successfully sent from the sender’s device. However, it does not indicate it has been delivered to the recipient’s device. The reason why the one tick appears instead of the message being blocked or not delivered at all has to do with how WhatsApp handles message sending.
How WhatsApp’s Architecture Allows Messages to be Sent
WhatsApp uses a client-server architecture to deliver messages. This means that the WhatsApp client app on the sender’s device connects to WhatsApp’s servers to send the message. As long as the sender has an internet connection and the message is successfully transmitted from the client app to WhatsApp’s server, the one tick will appear.
This is different from traditional SMS text messaging that relies on cellular networks and physical phone numbers. With SMS, if the recipient’s phone is out of range or switched off, the message may fail to be delivered and the sender would receive a notification of this failure.
But with WhatsApp, the client app does not communicate directly with the recipient’s device. It only needs to hand off the message to WhatsApp’s server. So even if the recipient has no internet connection or has WhatsApp closed at the moment, the message can still reach WhatsApp’s server, resulting in the one tick.
Why Messages are Not Blocked
There are a few key reasons why WhatsApp messages with only one tick are not blocked or failed to be delivered:
Reliable Internet Infrastructure
WhatsApp leverages the massive and reliable internet and server infrastructure that has been built over decades. WhatsApp itself maintains a globally distributed network of servers that are designed to handle billions of messages per day. Internet service providers also aim to maintain consistently high uptime and availability. This reliable infrastructure reduces the chances of complete network failures leading to blocked messages.
Queuing on WhatsApp’s Servers
When a WhatsApp message reaches WhatsApp’s server but cannot immediately be delivered to the recipient, the server queues and stores the message for later delivery. The message remains on WhatsApp’s server until the recipient’s device comes back online and is able to receive it. This prevents the message from being permanently blocked or lost.
Asynchronous Messaging
WhatsApp messaging is asynchronous. This means the sender and recipient do not need to be actively using the app at the same time for messages to be delivered. Recipients may be offline for hours or days, but can still eventually receive messages that were queued up for them on WhatsApp’s servers in the meantime. This asynchronous nature prevents messages from being blocked just because the timing is off.
Backups and Retries
WhatsApp servers maintain backups and retry sending queued messages periodically until they are successfully delivered. Even if the recipient’s device is offline for prolonged periods, the servers will continue retrying delivery behind the scenes until the message status changes from one tick to two ticks.
When Messages Get Blocked
Despite the reliable architecture, there are some scenarios where WhatsApp messages may still get blocked from being delivered:
Network Connectivity Issues
If the sender has no internet connectivity at the time they attempt to send the message, it will fail to leave their device and not reach WhatsApp’s servers. Prolonged internet outages for the sender or WhatsApp’s servers themselves can thus block messages.
Banned or Blocked Accounts
If the sender’s WhatsApp account has been banned or the recipient has blocked the sender, messages will fail to be delivered further than WhatsApp’s servers. WhatsApp has the ability to block accounts engaged in bulk messaging spam or other abusive behaviors.
Restricted Countries or Networks
In some countries, governments may intentionally block access to WhatsApp’s servers, preventing messages from reaching their destination. Internet service providers may also restrict access. If WhatsApp is entirely blocked, messages cannot be sent.
Recipient Runs Out of Storage
In rare cases, a recipient’s device may be so full that it cannot accept new WhatsApp messages. This would force WhatsApp’s servers to stop delivering new messages and block further ones until storage is freed up on the device side.
Troubleshooting Tips
If you are noticing your WhatsApp messages only showing one tick and not reaching recipients, here are some troubleshooting steps:
Check Your Internet Connection
Make sure you have an active internet connection on your device and try sending a test message. The one tick means your message left your device, but no connection means it is blocked entirely.
Restart Your Device and WhatsApp
Connection issues may be resolved by simply restarting your device and the WhatsApp app. This resets the network and app state which may resolve any temporary glitches.
Check WhatsApp Server Status
Use a site like downdetector.com to check if WhatsApp servers are down or experiencing an outage in your area. Global or regional outages on WhatsApp’s side could be blocking message delivery.
Try Different Networks
Switch between wifi and cellular data to test if messages go through on one network but not the other. Narrow down any network-specific blocking issues.
Check if You’re Blocked or Banned
Use another device and account to check if you can send messages to your primary number. If not, your account may be banned or blocked. Contact WhatsApp support for assistance with banned accounts.
Ask Recipients to Confirm Delivery
Have your contacts on the receiving end confirm if your messages are being delivered to them. If other users stop getting your messages as well, there may be an issue specific to your account.
Preventing Message Blocking
To reduce the chances of your WhatsApp messages getting blocked in the future:
Maintain Stable Connectivity
Use reliable WiFi networks or cellular data plans to ensure your device retains a connection, preventing intermittent message blocking.
Avoid Abusive Messaging
Don’t engage in spamming or harassment which could get your account banned. Stick to normal conversational messaging with your real contacts.
Update to Latest Version
Keep your WhatsApp app updated to the latest version. Newer versions may have bug fixes and improvements that reduceblocking issues.
Free Up Recipient Storage
If your recipients’ phones are frequently full, they may miss your messages. Encourage them to free up space so there’s room for WhatsApp’s queuing and retries.
Add Contacts as Favorites
Mark important contacts as favorites within WhatsApp’s interface. This may give your messages higher priority to break through blocking issues.
Why WhatsApp is Difficult to Block
While message blocking can still occur under certain conditions, WhatsApp has some inherent protections that make it resistant to large-scale message blocking:
End-to-End Encryption
WhatsApp messages are secured with end-to-end encryption, meaning the messages are indecipherable to anyone outside of the sender and recipient. This prevents networks and governments from being able to easily identify and block messages based on content.
Spread Out Servers
WhatsApp leverages hundreds of thousands of distributed servers across data centers around the world. This makes it difficult to cripple message delivery by targeting a few centralized server locations.
Backups and Multiple Protocols
WhatsApp maintains backup message queues as well as the ability to switch between protocols (WiFi, cellular data, etc.) for increased resilience. Blocking all message delivery thus requires blocking multiple delivery mechanisms across the stack.
Subscriber Base and Resources
WhatsApp has vast financial resources due to its billions of subscribers. This allows them to invest heavily in infrastructure, development, and legal resources to actively bypass or fight back against any message blocking attempts.
Comparison to SMS Texting
In contrast to WhatsApp’s architecture, traditional SMS text messaging relies on:
Cellular Carrier Networks
SMS delivery depends on cellular networks and physical SIM cards. If a carrier experiences an outage, texts can fail to deliver. There is no backup queuing on servers.
Centralized Infrastructure
SMS delivery may rely on just a regional cellular carrier’s single centralized text messaging center. A single point of failure.
Limited Protocols
Texting usually relies solely on the cellular network. If this is blocked, no messages can be sent. There are no alternative protocols.
Unencrypted Traffic
SMS text messages are typically unencrypted. This allows networks to more easily block specific messages based on keywords or other identifiable content.
Smaller User Base
Carriers have fewer subscribers than WhatsApp. Less revenue and resources to build reliable infrastructure or combat blocking attempts.
| Feature | SMS Texting | |
|---|---|---|
| Reliable infrastructure | Yes | No |
| Message queueing | Yes | No |
| Asynchronous | Yes | No |
| End-to-end encryption | Yes | No |
Conclusion
In summary, WhatsApp is architected in a resilient way that allows messages to reach its servers and queue up for delivery even when recipients are offline. This prevents the app from outright blocking messages and instead results in the one tick delivery indicator. However, there are still some circumstances where messages may fail to be delivered further and get stuck in limbo. Checking connectivity issues, troubleshooting account restrictions, or waiting for the recipient to come back online can help resolve these rare but still possible blocking scenarios. Ultimately, WhatsApp’s distributed server infrastructure and asynchronous delivery mechanisms make it much harder to block compared to traditional cellular text messaging.