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What is TTL? and what does TTL= 64/128/255 means?

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Tags: Networking, Operating Systems, Security

What is TTL? and what does TTL= 64/128/255 means? explain in deep as you can with security perspective/POV. 🙂

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Re: TTL

In reply to What is TTL? and what does TTL= 64/128/255 means?

https://en.wikipedia.org/wiki/Time_to_live might be deep enough for you. If not, tell why it doesn’t suffice.

[birdmantd]

Reply To: What is TTL? and what does TTL= 64/128/255 means?

In reply to What is TTL? and what does TTL= 64/128/255 means?

Try this information

What Is TTL (And How Do You Choose the Right One)?

or do an internet search of your original question.

Typically, the 3 #’s you posted reflect a finite amount of memory, but the last number is 256 and should not be listed as 255. This is found mostly when referring to HDD/SDD or system memory. 64 is half of 128 and 128 is half of 256. This has been standard in computer/electronic devices for several decades.

• This reply was modified 1 year, 3 months ago by birdmantd.
• This reply was modified 1 year, 3 months ago by birdmantd.

Re: TTL

In reply to Reply To: What is TTL? and what does TTL= 64/128/255 means?

The valid values of a TTL are (decimal)1 to 255. That’s binary 1 to 11111111, or all values except 0 that fit in a byte. Given what the TTL means, the value 0 makes no sense.

https://networkengineering.stackexchange.com/questions/69688/confusion-about-ttl-when-pinging explains it’s not something the average user needs to worry about. Average users don’t write OS’es or router software.

Reply To: What is TTL? and what does TTL= 64/128/255 means?

In reply to What is TTL? and what does TTL= 64/128/255 means?

TTL, or Time To Live, is like a self-destruct timer for data packets on a network. It prevents them from getting lost or looping forever, causing problems.

Here’s the security angle:

High TTL (like 255): This lets packets travel far, but it can also be risky. Imagine a fake package (like a spy in disguise) with a high TTL – it could sneak past security easier. Also, bad guys might use high TTL packets to overload a network (denial-of-service attack).

Lower TTL (like 64): This keeps packets on a tighter leash, making it harder for tricksters to use them for mischief. It also helps networks run smoother by cleaning up old data.

The key is finding the sweet spot – a TTL high enough for real messages to get where they need to go, but low enough to keep security risks in check.

Thanks

In reply to Reply To: What is TTL? and what does TTL= 64/128/255 means?

This cleared a my thinking about TTL i now know more clearer thanks for your explanation. 🙂

What is TTL? and what does TTL= 64/128/255 means?

In reply to What is TTL? and what does TTL= 64/128/255 means?

TTL, or Time To Live, is a crucial security and efficiency feature built into every data packet traveling across your network. It acts like a self-destruct timer, ensuring packets don’t endlessly loop around the internet, causing congestion and potential security risks.
It stops messages from getting stuck and causing problems. Each message gets a number of “jumps” it can make between routers (like pit stops) before disappearing. This prevents endless loops and keeps the internet running smoothly. It also helps security by stopping fake messages from flooding the network.

255: This is the highest default TTL value on most operating systems. It allows packets to travel a significant distance across the internet before being discarded.

128: This is another common value, often used for internal network traffic or within a specific geographic region.

64: A lower TTL value is typically used for local network traffic or applications that don’t require long-distance travel.

Thanks

In reply to What is TTL? and what does TTL= 64/128/255 means?

This cleared a my thinking about TTL i now know more clearer thanks for your explanation.It was very simple to imagine and understand 🙂

Re: What is TTL? and what does TTL= 64/128/255 means?

In reply to What is TTL? and what does TTL= 64/128/255 means?

TTL is a computer networking term that refers to the lifespan of data on the network. Its full form is Time To Live. There are certain values that are crucial for optimizing network and reliability.

What is the function of TTL?

• It embeds within the header of a data packet.
• TTL is also a self-destruct timer which dictates how long a packet can exist on the network after router is discarded.
• Every router the packet passes through decrements (reduces by 1) the TTL value. It prevents the endless loops.

How Does TTL helps in Security?

• Without TTL, you can easily end loops between packets of routers due to misconfigurations. But with TTL the packets are eventually discarded which prevents network congesion and DDoS attacks.
• A lower TTL reduces the window for attackers to potentially intercept or tamper with data packets as they travel across the network.

As far as your TTL Values (64/128/255) is concerned. Here is an explanation. So, the TTL is typically represented as an 8-bit value, ranging from 1 to 255. The given TTL value comes under the lower category. It offers the self-destruct for packets, limiting their exposure time on the network and enhancing security.

[Author]

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