"Kaminski, Shawn G" wrote: > In your reply below, you're saying that "A half-duplex Ethernet interface > (whether on a bridge, switch, router, server, or PC) monitors for a > collision while sending. If a collision occurs, the interface (I assume > you're talking about the interface on the router/bridge) re-transmits the > frame". So this tells me that a router/bridge Ethernet interface is able to > re-transmit a frame. Correct? Then why do you state in the next paragraph > "The CCIE tests expect you to know that neither a bridge nor router > re-transmits if a frame experiences a bit error or gets lost somehow". Could > you please clarify further? Thank you!
I'm sure Priscilla will clarify her comments, but I'd like to say something. You (Shawn) correctly distinguish the two issues that Priscilla introduced: * retransmission of frames that collide * retransmission of frames are corrupted CSMA/CD Ethernet interfaces are built to detect collisions. If there is a collision, the multiple senders back off, hopefully for different time periods, and retransmit the frames that collided. On the other hand, a corrupted frame is a frame that does not collide with another frame but for some reason arrrives at the receiver with one or more bit errors. Bit errors are bits that are inserted, deleted, or toggled (0 to 1, 1 to 0). The cinematic taxonomy here is: * The Good: a frame that does not collide with another frame on the transmission medium and arrives at the receiver exactly as it was sent, with no bit errors. * The Bad: a frame that does not collide with another frame but nevertheless arrives at the receiver with one or more bit errors. * The Ugly: a frame that collides with another frame. -- TT Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=43491&t=43459 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
