Speed Up Your AppleTalk Network

Mac128

Well-known member
I've seen this Tops repeater before, http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170532417443

But this is the first I have seen of this Tops Flashbox (I think), http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170532390654

770Kbps on an AppleTalk network! Wow! Now why wouldn't Apple implement this themselves? Seems like a strong selling point.

On a side note, I love ebay sellers who not only charge reasonable starting prices (letting the market set the value), and know when to use the word rare, but also have real knowledge about what they are selling and don't just copy and paste content from Wikipedia.

 

trag

Well-known member
Hmmm.. Well I remember something about being able to externally clock the serial ports for higher performance. This was a little used/remembered feature that Apple built into their machines. But I wonder if that is what this is using. It seems like it would have to be. I wonder how the external mechanism signals the Mac that the port will take its clock externally. Perhaps the associated software handles that?

 

Anonymous Freak

Well-known member
Apparently the "AppleTalk" port on a Mac is capable of up to 2 Mbps when externally clocked.

To my understanding (I worked somewhere in the early '90s that had an externally-clocked AppleTalk network,) there is no software layer needed, the hardware just accepts the external clock.

 

Anonymous Freak

Well-known member
Reading the auction in more detail, it looks like this is *NOT* a standard AppleTalk accelerator; but rather a device that can do both AppleTalk *AND* a separate third-party faster protocol.

 

Bunsen

Admin-Witchfinder-General
Didn't the Farallon Localtalk-ethernet adapters also perform this overclocking trickery?

 

Anonymous Freak

Well-known member
My two don't. It was a feature Apple made a fairly big deal about in the early days of LocalTalk; but I think once Ethernet became the obvious successor, Apple stopped bothering with LocalTalk. Which is funny, because you'd think that would be EXACTLY when the external-clock feature would be most useful! After all, LocalTalk's externally-clocked maximum was 2 Mbps, which happens to be the same speed as coax Ethernet. That would seem to be a perfect pairing for LocalTalk-to-Ethernet adapters.

 

Charlieman

Well-known member
I only saw them in the wild once in the 1990s, and that was to pull them out and replace them with standard LocalTalk boxes...

Didn't Radius perform some strange hacks with LocalTalk for the Rocket cards?

 

Scott Baret

Well-known member
If such devices do exist, I'd be curious to see what sort of effect, if any, they would have on notoriously slow/poorly designed networking hardware (specifically the Power Mac 5xxx/6xxx series).

 

Bunsen

Admin-Witchfinder-General
Farallon has a unique solution that provides a faster connection / EtherMac and EtherWave adapters. By clocking the LocalTalk port at a higher than usual speed (something even the first Macintosh allowed), these adapter let your Mac communicate over ethernet at about 3x the speed of LocalTalk. / Drawbacks include price (compared to a bridge) and no support for OpenTransport.
Here, found here

 

Charlieman

Well-known member
EtherWave and EtherMac are crude serial hacks that bridge a LocalTalk to an Ethernet network. In the old days when 10 mbps ethernet was standard, they sufficed. Dayna made similar products.

 

H3NRY

Well-known member
FlashTalk was a late version of TOPS which ran the AppleTalk protocol at 2 speeds, normal 230 Kbps and triple speed. In order to maintain compatibility with non-Flash devices, the driver added a secret handshake to every normal packet.

(Normal speed) Hi, can you go fast?

Hi, yes I'm fast. (Switch to fast speed)

Hi, I have data for you.

OK.

data packet

Got it. (drop back to normal)

or

(Normal speed) Hi, can you go fast?

Huh?

(still normal speed) Hi, I have data for you.

etc.

For large data packets it did speed things up about 2X overall. For short packets, it actually slowed transfers due to the extra overhead, and the fast packets caused all slow devices on the network to reset their serial ports because of the "noise". It was mostly used in all-PC networks with Sun's FlashTalk cards, where it didn't disrupt normal LocalTalk traffic. It was also not 100% compatible with active hubs like Farrallon's, Nuvotech's, and PCon's. Sun lost interest in TOPS within a few months of buying the company, and the technology never caught on. Apple disliked it because it bogged down large networks with lots of short packets, it was expensive, it was NIH, and it didn't work very well with Apple's own LocalTalk wiring setup. It worked much better with phone wire.

 
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