Cyclades-PR4000

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Parameter

Description

Layer 3 Window Size

The layer 3 (packet) level window represents the number of sequentially

 

numbered packets that can be sent before an acknowledgement must be

 

received. This number may be negotiated if the Window Size Facility is utilized

 

(see last parameter in this table).

Layer 2 Window Size

The layer 2 (frame) level window represents the number of sequentially

 

numbered frames that can be sent before an acknowledgement must be

 

received. The frame numbers are independent of the packet numbers.

Packet Size

The packet size to be sent across the interface. This number may be

 

negotiated if the Packet Size Facility is utilized (see last parameter in this table).

Number of Retries N2

Number of times an information frame can be resent, without response, before

 

the link is considered down.

TL

Time the frame level waits for an acknowledgement for a given frame before re-

 

sending it.

T2

Time that can elapse, after receiving a frame, until the router must send an

 

acknowledgement.

T21

Call Request response Timer. After this time has elapsed, the DTE sends a

 

Clear message.

T23

Clear Request response Timer. After this time has elapsed, the DTE

 

retransmits the Clear message.

Negotiable Facilities

Initiates facility negotiation during virtual circuit creation.

Send Facility

Determines which facilities are negotiated during virtual circuit creation: Packet

 

size is part of the flow control parameters negotiation, Throughput is part of the

 

throughput class negotiation, and N3 Window (Level 3 Window Size, above) is

 

part of the flow control parameters negotiation.

Chapter 10 - Data-Link Protocols (Encapsulation)

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