Avocent Cyclades-PR4000 - Manual (Page 89)

Chapter 10 - Data-Link Protocols (Encapsulation)
Cyclades-PR4000
89
X.25 Menu (Continued)
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.