The link layer refers to the device drivers providing access to the physical layer, which could be numerous mediums, such as serial links or Ethernet devices.

链路层是指提供对物理层访问的设备驱动程序，这可以是各种介质，例如串口链路或以太网设备。

youdao

Random or serial access: will the tool move at random through the postmortem artifact, or will it access the contents serially?

随机或串行存储：工具采用随机还是串行方式访问后期工件？

youdao

Before Version 2.0, this access was limited to serial consoles via secure console servers.

IPMI 2.0之前，这种访问局限于通过安全控制台服务器的串行控制台。

youdao

But his probing into queuing was rebuffed by the airports, which he said were "quite secretive and edgy about the whole issue", offering him limited access to find out about the serial queuing that is air travel.

BBC: Good queue guide

The doctor who took over serial killer Harold Shipman's former practice in Greather Manchester has backed plans to allow easier access to patient records.

BBC: Harold Shipman successor backs online records plan