Hitachi US7070447-001 manual Physical Media Specifications, Common Ethernet Errors

Draft Level—Hitachi Confidential

HiSpeed Switch Troubleshooting GUide

Physical Media Specifications

10BASE-5	10BASE-2	10BASE-TX	10BASE-FX
		(Unshielded Twisted
(Thick Coaxial cable)	(Thin Coaxial cable)		(Fiber Optical Link)
		Pair-UTP)

Max. stations per segment

Max. segment length

Connector type

Cable type

1024	1024	1024	1024
500 meters	185 meters	100 meters	200 meters
DB15 AUI	BNC	STAR	STAR
RG-11	RG-58	Cat 3 or 5	62.5/125 mm
			or 9/125 sm

Common Ethernet Errors

collisions	Occurs when more than one device is transmitting
	simultaneously. Collisions are considered to be ‘normal’
	in an Ethernet environment. CSMD/CD is designed to
	detect and correct for this.
late collisions	A collision detected after 64 bytes have been
	transmitted. May indicate a malfunctioning NIC/cable, or
	a network segment that has exceeded the maximum
	length.
excessive collisions	The maximum number (16) of consecutive collisions
	allowed between endstations contending for the wire.
	Possibly caused by exceeding the maximum number of
	users on a given segment, length of cable, or jabbering
	NIC.
undersized frames/	Frames smaller than the minimum Ethernet frame size of
runts	64 bytes a.k.a. ‘runts’. Presumed to be a fragment
	resulting from a collision.

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