单项选择题
Error detection schemes check errors in the data packets by reading which field frame IDs?（）
A.MTU B.PDU C.FCS D.Flag E.MAC F.BRI
单项选择题 Which frame field do error detection schemes view to perform their function?（）
单项选择题 Which of one the following fields is contained within an IEEE Ethernet frame header?（）
单项选择题 Which device enables a router serial interface to connect to the ISDN BRI?（）
