wendy

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According to IEEE 802.2 LLC spec, what is the maximum transmit value
for LLC flow control?

Many thanks in advance,
Rygel
 
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In article <d5db4614.0411300830.3fcc127a@posting.google.com>,
rygel_16@hotmail.com (Wendy) wrote:

> According to IEEE 802.2 LLC spec, what is the maximum transmit value
> for LLC flow control?
>
> Many thanks in advance,
> Rygel

LLC-2 provides seven bits for the frame sequence number, thus there can
be a maximum of (2^7 - 1) = 127 outstanding, unacknowledged frames. The
"sliding window" is used for both flow and error control.

Note that this applies ONLY to LLC Type 2, which is not commonly used
(at least not on Ethernet). LLC Type 1 provides no flow control at all.


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Rich Seifert Networks and Communications Consulting
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wendy

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Interesting!

Boson test exams believe it to be 255, whilst TestKing believe it to be 1023!

Go figure!

Rygel


Rich Seifert <usenet@richseifert.com.invalid> wrote in message news:<usenet-EAC710.11183330112004@news.isp.giganews.com>...
> In article <d5db4614.0411300830.3fcc127a@posting.google.com>,
> rygel_16@hotmail.com (Wendy) wrote:
>
> > According to IEEE 802.2 LLC spec, what is the maximum transmit value
> > for LLC flow control?
> >
> > Many thanks in advance,
> > Rygel
>
> LLC-2 provides seven bits for the frame sequence number, thus there can
> be a maximum of (2^7 - 1) = 127 outstanding, unacknowledged frames. The
> "sliding window" is used for both flow and error control.
>
> Note that this applies ONLY to LLC Type 2, which is not commonly used
> (at least not on Ethernet). LLC Type 1 provides no flow control at all.