What Happens When a Router Receives a Packet with a TTL of 0?

What Happens When a Router receives a Packet with a TTL of 0?

The router is a wireless network device that helps transfer data to other connected devices. Do you know the mechanism behind the working process of a router? What happens when a router receives a packet with a TTL of 0?

TTL means Time-To-Live. You will get to know all the details later. We will answer all your queries. This will help you in troubleshooting any issues with the router in future. There are a lot of important things that you need to know. So, let’s jump in. 

The Router’s Working Process

What happens when a router receives a packet with a TTL of 0? First, you must know the main concept behind the working process of the router. Let’s say that your home router is connected to the PC. On the other hand, the router is also active within the Ethernet connection. The case is not as simple as you see. Your home router is also connected to two other routers that are located with the ISP. Two more systems are also connected to the additional two routers. This entire process completes a LAN network, which is how a router works. 

The Transfer Process of Data Packets 

When the home router receives a data packet from the main or local server, it scans the routing table of the packet. This helps in determining the target IP address. The same compatible request of the data packet is already made by the respective system a few seconds ago. After matching the IP address, the data packet is being sent to the respective client/system. 

ICMP, A Brief Overview

The Internet Control Message Protocol is a network layer, and it helps all the network equipment to detect any ongoing issues. Certain aspects are related to what happens when a router receives a packet with a TTL of 0? The main aspect of the ICMP is to determine whether the data packets have reached their destination or not. In addition to that, the protocol also matches the value and checks whether it is zero or one. 

The TTL – A General Overview

A data packet can hop through the network. The amount of time that data packets take to hop around the network until a router receives is known as the TTL. You must get a brief detail about the TTL if you want to know the answer to what happens when a router receives a packet with a TTL of 0? The TTL is designed for a specific reason. The hopping of the data packet can go for a lifetime when it enters into the infinite loop. To resist this, the concept of TTL has been introduced. 

Role of the Router Towards TTL(0)

The router drops the packet and delivers an ICMP TTL message to the main server. Here, the main server is the host. Despite that, the host/main server will send the traffic over the network, but the sent data packets may not reach the right destination system. 

Now, you will answer the question of what happens when a router receives a packet with a TTL of 0? When the TTL is 0, the host server discarded the desired data packet, and it will not reach the host. 

The router ignores those data packets. When a data packet is sent from the server, it is normally 255. On each hop, 1 is being subtracted every time. If your router drops the packet, it turns to 0. 

What happens when the TTL is 1?

Hopefully, you have got the answer to what happens when a router receives a packet with a TTL of 0? Now, the value changes to 1 with the same question. When the TTL value is 1, the LSR ignores and drops the packet. Furthermore, it also sends an ICMP message that is the time has exceeded. The type is 11 with code 0 to the host server. The same process will occur when the TTL is 1 or the TTL is about to expire. 

Conclusion 

Hopefully, you have understood the answer to the question of what happens when a router receives a packet with a TTL of 0? Furthermore, it seems that you had gone through the sections when the value was 1. It is quite easy to study these matters with a basic understanding of computer networking. Make sure that your router works fine without any loss of data packets. 

Leave a Reply

Your email address will not be published.