(Manual) maximum segment size(MSS)

2014-02-11 wcdj


The maximum segment size (MSS) is the largest amount of data, specified in bytes, that acomputer or communications device can handle in a single, unfragmented piece. For optimumcommunications, the number of bytes in the data segment and the header must add up toless than the number of bytes in the maximum transmission unit (MTU).

The MSS is an important consideration in Internet connections, particularly Web browsing. Whenthe Internet's Transmission Control Protocol (TCP) isused to achieve an Internet connection, the computers being connected must each agree on, and thenset, the MTU size acceptable to both. Typical MTU size in TCP for a home computer Internetconnection is either 576 or 1500 bytes. Headers are 40 bytes long; the MSS is equal to thedifference, either 536 or 1460 bytes. In some instances the MTU size is less than 576 bytes, andthe data segments must therefore be smaller than 536 bytes.

As data is routed over the Internet, it must pass through multiple gateway routers.Ideally, each data segment can pass through every router without being fragmented. If the datasegment size is too large for any of the routers through which the data passes, the oversizesegment(s) are fragmented. This slows down the connection speed as seen by the computer user. Insome cases the slowdown is dramatic. The likelihood of such fragmentation can be minimized bykeeping the MSS as small as reasonably possible. For most computer users, the MSS is setautomatically by the operating system.


参考

[1] http://searchnetworking.techtarget.com/definition/maximum-segment-size




评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值