| Title: | FDDI - The Next Generation |
| Moderator: | NETCAD::STEFANI |
| Created: | Thu Apr 27 1989 |
| Last Modified: | Thu Jun 05 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2259 |
| Total number of notes: | 8590 |
Hi all,
I have a question coming from the customer:
he's testing a PCI-FDDI board (DEFPA-UA) plugged in a AlphaStation
200 4/233. In the other side he used a SBC (Medulla 233 but it does'nt
matter). He ran a receiver program on SBC and a sender program on
AlphaStation. He measured 70Mbit/sec. Today he tried to run also the
receiver program on AlphaStation mantaining the physical connection
between the systens to have the link on. He measured 120Mbit/sec.
The question is: does it mean that if I connect two AlphaStation I get
that speed? If not (this is what I suppose) what does it mean?
Thanks in advance.
/Siro.
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 1741.1 | Full Duplex operation ? | LARVAE::HARVEY | Baldly going into the unknown... | Tue Jul 11 1995 06:12 | 18 |
If I understand your configuration correctly it sounds like you have full-duplex FDDI in operation ie. 2 systems only connected to each other. Digital FDDI chipsets - and possibly those made under licence by Motorola (and AMD ?) - have had this feature built-in (but lying dormant). So, if the above direct system-system scenario arises or if you plug a system into a GIGAswitch/FDDI port, then the two negotiate away the standard Token passing mechanism in favour of full duplex operation. As soon as a third system is included into the FDDI then a ring is formed and the Token mechanism is required.. Systems have been seen to give up to @160Mbps I/O but this all depends on the system loadings, applications etc. I'm sure the topic is covered elsewhere in this conference, I just don't know the references. Rog | |||||