单项选择题
A.Packet-based switching devices B.VPI/VCI-based switching devices C.Non-Packet-based devices D.None of the above E.A and B
A.TE middle point B.TE tail end C.TE head end D.All TE nodes along the path E.Independent server
A.0ms B.10ms C.500ms D.1s E.5s F.30s