How is the TCP MSS of an AR interface changed

The TCP MSS specifies the maximum length of TCP packets that can be received by a device. When setting up a TCP connection, the local and peer devices negotiate an MSS value to determine the maximum data length of TCP packets. If the length of TCP packets sent from the peer device exceeds the MSS value, the packets are fragmented. To prevent TCP packets from being fragmented, you must configure a proper MSS based on the maximum transmission unit (MTU). The MTU determines whether IP packets will be fragmented. If the size of an IP packet exceeds the MTU, the IP packet will be fragmented. To ensure that a complete packet is transmitted properly, the MSS value plus all the header lengths (TCP header and IP header) cannot exceed the MTU. For example, if the default MTU value of an Ethernet interface is 1500 bytes, to ensure that packets are not fragmented, the maximum MSS value can be 1460 bytes. 1460 = 1500 �?20 (TCP header) �?20 (IP header) You are advised to set the MSS value to 1200 bytes.
An improper TCP MSS value may lead to slow network access. To set the TCP MSS, run the following commands:
[Huawei] interface gigabitethernet1/0/0
[Huawei-GigabitEthernet1/0/0] tcp adjust-mss 1200

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