Differences Between MSS and MTU
This article will help you in providing a good understanding of the comparison between MSS and MTU concepts. Before diving into main context first let us understand what does MSS and MTU mean.
MSS
MSS stands for Maximum TCP Segment Size. It is a TCP header field that contains data bits that are used to identify the device with the highest data capacity. MSS adheres to the three-way handshaking used in the TCP/IP handshake, which complies with all of the fundamental networking protocols. The MSS and MTU are comparable, but the MSS is utilized with the layer 4 TCP protocol. The more sophisticated and secure variant of MTU is called MSS. It is in charge of choosing the component that causes the fragmentation. MSS is a very crucial aspect in terms of web browsing. MSS is established mainly by the Operating System(OS) when a TCP handshake takes place in an SYN packet.
MTU
Maximum transmission unit, or MTU, is a term used in networking and operating systems. The largest packet size that may be transmitted in a single unit across a network connection is specified. The size of the MTU determines the maximum amount of data that may be carried across a network in terms of bytes.
A larger MTU reduces the overhead by enabling greater data transfer over a single connection. On the other side, the lower MTU's smaller size allows it to transfer data more rapidly, which reduces network latency. The MTU size has to be changed to best satisfy both requirements.
The default size for the maximum transmission unit is 1500 B, the largest unit permitted by the Ethernet standard.
Characteristics/Features
- The MTU's size and data transfer rate are mutually exclusive. When the MTU is larger, more data is sent simultaneously from the source to the final destination.
- The needs of the network management define the MTU size.
- The MTU size is retransmitted if it exceeds the router's capacity, which adds latency.
- It is the optimal packet size for the network.
MTU Working
As stated by the Internet's Transmission Control Protocol, the largest protocol data unit size that may be transferred from source to destination is MTU = 750 B. (TCP). In such a circumstance, the following possibilities may take place:
- If the system transmits packets that are bigger than the MTU, which in this case is packet size > 750 B, they will be split into smaller packets so that they don't exceed the maximum packet size. The act of fragmenting involves dividing a large data packet into smaller ones such that no one chunk exceeds the maximum frame size. These are later reassembled at the client's final location.
- The network connection transmits packets in a single frame if the system sends them and they fit inside the MTU. Significantly smaller than the MTU packets, however, may lead to network inefficiency and an increase in latency. Reassembling packets is not required in this case.
Applications
The maximum transmission unit is suitable for the following applications:
- TCP heavily relies on MTU to determine the optimum packet size for use on the internet.
- It is coupled to the Ethernet protocol and is referred to as a protocol data unit (PDU).
Difference between MSS and MTU
S.No. | MSS | MTU |
1. | MSS stands for Maximum TCP segment Size. | MTU stands for maximum transmission unit in the MTU protocol. |
2. | For the TCP header, MSS uses the three-way handshake protocol. | MTU does not use the TCP header handshaking mechanism. |
3. | In contrast to MTU protocols with lower MTU values, MSS does not use data packet fragmentation | MSS takes use of data packet fragmentation as opposed to the higher value of the MTU protocol. |
4. | It calculates and establishes how much segmentation takes place at each transport and tunnelling layer of the TCP protocol | It doesn’t mention the level of fragmentation done in each layer of TCP protocol |
5. | It lacks the ability to transfer data across network routers | The network gateway's capacity is determined by the most data bytes that can be transmitted from one router terminal to another. |
6. | It uses layer 4 TCP/Ip protocol | It uses the layer-2 TCP/IP protocol. |
7. | It establishes the largest possible size for the payload of data blocks that can be transmitted. | It establishes the maximum quantity of data that may be sent between two network routers. |
8. | MSS = MTU – 40(IP header + TCP header) | MTU = MSS + 40 (IP header + TCP header) |
This is all about comparison between MSS and MTU. Hope you understood this topic.