MTP2:Architecture: Difference between revisions

Revision as of 13:28, 25 August 2009

MTP Level 2 defines the functions and procedures of the signaling system for providing reliable transfer of signaling messages over a signaling link. The MTP2 layer is a service provider to the MTP3 Link layer. The MTP2 layer is a service user of line interfaces / line services as seen in the shown in the figure below.

MTP2 can be used in conjunction with an above local MTP3 layer and can be used as a standalone and communicates with remote MTP3 layer (host application). See MTP2 connection mode for more information.

A MTP2 Link must be associated with one line interface/service. It’s a 1-to-1 association. MTP Level 2 defines the functions and procedures of the signaling system for providing reliable transfer of signaling messages over a signaling link.

IMPORTANT NOTE: It is important to ensure that the received and transmitted clocks of the line interface/service were synchronized. This can be useful for removing/limiting undesirable FIB and BSN errors. (See section “Clock Configurations” in the TB640 user’s guide.)

Priorities

No pre-emption of data occurs in the process of being transmitted or requiring retransmission. Only a single congestion priority is supported for ANSI and ITU. For a TTC/NTT link, transmitted data buffers are prioritized based on the priority indicated by MTP Level 3.

Flow control

The MTP Level 2 software regulates data flow when resource utilization (such as buffer pool size or queue length) reaches specifies thresholds. For each threshold, MTP Level 2 performs one of the following actions:

Informs the layer manager about flow control.
Sends a link status signal unit with status "B" (busy).
Sends a flow control indication to the upper layer.

The MTP Level 2 software prevents deadlocks and overload conditions from occurring.

@@ Line 1: / Line 1: @@
-[[MTP2 Layer|MTP Level 2]] defines the functions and procedures of the signaling system for providing reliable transfer of signaling messages over a signaling link. The MTP2 layer is a service provider to the MTP3 Link layer. The MTP2 layer is a service user of [[Web_Portal_Tutorial_Guide#Line_Interfaces|line interfaces / line services”]] as seen in the shown in the figure below.
+[[MTP2 Layer|MTP Level 2]] defines the functions and procedures of the signaling system for providing reliable transfer of signaling messages over a signaling link. The MTP2 layer is a service provider to the MTP3 Link layer. The MTP2 layer is a service user of [[Web_Portal_Tutorial_Guide#Line_Interfaces|line interfaces / line services]] as seen in the shown in the figure below.
-[[Image:MTP2-architecture.jpg|700px|MTP2 architecture schematic]]
+[[Image:MTP2-architecture.jpg|700px]]
-MTP2 can be used in conjunction with an above local MTP3 layer and can be used as a standalone and communicates with remote MTP3 layer (host application). See the connection mode table in the MTP2 Configuration section.
+MTP2 can be used in conjunction with an above local MTP3 layer and can be used as a standalone and communicates with remote MTP3 layer (host application). See [[MTP2:Connection mode|MTP2 connection mode]] for more information.
-[[Image:filename|thumb|widthpx| ]]
+[[Image:MTP2-layer-hierarchy.jpg|600px| ]]
-A MTP2 Link must be associated with one Trunk instance. It’s a 1-to-1 association. MTP Level 2 defines the functions and procedures of the signaling system for providing reliable transfer of signaling messages over a signaling link.
+A MTP2 Link must be associated with one line interface/service. It’s a 1-to-1 association. MTP Level 2 defines the functions and procedures of the signaling system for providing reliable transfer of signaling messages over a signaling link.
-'''IMPORTANT NOTE:''' It is important to ensure that the received and transmitted clocks of the Trunk were synchronized. This can be useful for removing/limiting undesirable FIB and BSN errors. See section “Clock Configurations” in the TB640 user’s guide.
+'''IMPORTANT NOTE:''' It is important to ensure that the received and transmitted clocks of the line interface/service were synchronized. This can be useful for removing/limiting undesirable FIB and BSN errors. (See section “Clock Configurations” in the TB640 user’s guide.)