Mitel Voice Processing Solutions Instructions Manual

							Configurating MESA-Net Async Hardware and Links 
on configuritig these parameters, refer to CP 5712 in the procedural part of this 
chapter. 
Baud Rate 
MESA-Net software transmits and receives data at 300 to 57600 baud on each link. 
Total throughput per system varies by Series 6 server model. For highest 
throughput, use the Serial 16132 Card in the Centigram server. 
High baud rates minimize transmission costs, but public switched networks may not 
be able to support high speed transmissions. The communications device will also 
be limited to a certain maximum baud rate. Configure the link for the highest rate 
the equipment allows that will still provide error-free transmission. 
The default baud rate for MESA-Net Async links is 9600. The recommended rates 
for the various modems are: 
@ 
Concord Trellis 296 9600 
0 
Concord DialAccess 296 9600 
0 Microcom QX V.32C 9600 
8 
ATT Paradyne 28,800 
8 
US Robotics 28,800 
e 
WorldBlazer 
19,200 
0 
Telebit T2500/World Blazer 9600 
Hardware types for these devices are pre-programmed into the MESA-Net software. 
ata Bits, Stop Bits, and Parity 
MES+4-Net link default settings are 8 data bits, 1 stop bit, and no parity. The 
settings must match on both nodes in-a. MESA-Net session. 
Flow Control 
MESA-Net links have flow control enabled by default. The nodes use flow control 
when exchanging messages if one side is processing slower than the other, such as if 
one side is experiencing a heavy call volume. 
Configuring Failure Counts 
MESA-Net can tolerate noisy lines and dropped data bits. Every packet of data that 
is sent between nodes includes checksums. Checksums are unique keys calculated 
from the message data. When the data is received at the other end of the connection, 
the same calculation is done, and the result is compared with the transmitted 
checksum. If the checksums are not identical, a transmission error has occurred. 
The receiving end increments its receive fail count and sends a message back to the 
sending node, indicating that there was a transmission error. The sending node 
increments its send fail count and resends the data. 
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							Configurating MESA-Net Async Hardware and Links 
The send ftil count and receive fail count are reset to zero each time an error-free 
block of data is transmitted. The default: limit for send fail count and receive fail 
count is 7. This means that if there are 7 consecutive errors on a single block of data, 
the line is too “dirty” for successful communication. The node then executes the 
disconnect actions of the hardware type associated with the link, which breaks the 
connection. 
The number of times that the system attempts to establish a good connection 
(Maximum Call Setup Tries) and the time that the system waits before making 
another attempt (Call Setup Retry Interval) are configured from the Modify Netq 
Limits Menu. (See Chapter 10, “Configuring the Netivork Queue,” for more 
information.) 
For step-by-step instructions on configuring failure counts, refer to CP 5712 in the 
procedural part of this chapter. 
onfiguring the Serial Port 
You use the Serial Port Device Type menu to assign one serial port to each link. The 
menu shows three choices: CT1 Smartcard, Serial Port 1, and Serial Port 2. You 
must select CT1 Smartcard; it applies to both Smartcards and Serial 16/32 cards. 
For step-by-step instructions on configuring the serial port, refer to CP 5712 in the 
procedural part of this chapter. 
imeout Parameters 
This section describes the three timeout parameters for MESA-Net links: data 
receive timeout, resend timeout, and node inactivity timeout. For step-by-step 
instructions on configuring the timeout parameters, refer to CP 5712 in the 
procedural part of this chapter. w” 
When a MESA-Net node answers a call from another node, the modem sends a 
suing to the answer link serial port indicating that a hardware connection has been 
established. The MESA-Net software of the answering node starts the data receive 
timer, and waits for a query from the originating node. The originating node then 
asks for confirmation that a software connection has been established. 
The data receive timeout is the maximum time that the answering node allows to 
elapse between the time it receives the signal from the hardware and the time it 
receives the query from the originating node. The default value is 60 seconds. If the 
data receive timeout is exceeded, the answering node executes the disconnect actions 
specified in the hardware type assigned to its answer link. 
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							Configurating MESA-Net Async Hardware and Links 
send Timeout 
A sending node expects a confirmation message back from a receiving node every 
time it sends a packet of data. The sending system does not wait for confirmation of 
receipt of one packet before sending another packet (which would be too inefficient), 
but it does expect confirmation messages to be sent in a timely manner. The resend 
timer tracks the time between confirmation messages. 
The resend timer is started immediately after the first packet of data is sent, and is 
restarted whenever a confirmation message is received. The resend timeout is the 
maximum time allowed between any two confirmation messages. The default value 
is 60 seconds. 
If the timeout value is reached, the sending system sends a query to the receiving 
system, asking for verification that the data was received. This query is repeated 
every 10 seconds until confirmation is received or until some other timeout causes a 
breakdown of the link. 
Node Inactivity Timeout 
Both send and receive nodes start an inactivity timer every time they send data or a 
message to the other node, and reset the timer every time they receives data or a 
message back from the other node. A node disconnects the call when the inactivity 
timeout is reached. The default Node Inactivity Timeout is 120 seconds. 
Links Worksheet 
Fill in the Links Worksheet to gather all of the information that you need to 
configure MESA-Net Async links. The sample worksheet below is filled out as an 
example. A blank worksheet is at the end of this chapter. 
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							Configurating MESA-Net Async Hardware and Links 
Assignments 1 
I 
1 Link Number 
I 
Device Number Serial Port Number I q 
I 
57600 
I a 1200 
I 38400 4800 300 
/ Data Bits: 7a Stop Bits: a 1 2 
I Even 
Odd Space 
I 
1 Send Fail Count 
Receive Fail Count 
q 7 
I (l-255) 
(l-255) 
I 
1 Data Receive Timeout 
i 
i Resend Timeout 
q 60 seconds-“’ 
I 
1 Node Inactivity Timeout 6o seconds 
cl 
I 
igure 4-3 Sample Links o&sheet 
hanging the Answer or riginate link Assignment 
In the default configuration for MESA-Net, link 1 is an originate link, link 2 is an 
answer link, link 3 is an originate link, link 4 is an answer link, and so on. If you 
need to change these default link assignments, see CP 
5715 in the procedural part of 
this chapter. 
You may need to change the default link assignments if, for example, a network has a 
small node that receives far more messages than local users send. In this case, you 
4-13  
						

							P 
Configurating MESA-Net Async Hardware and Links 
can configure both links as answer links. Since MESA-Net operates in full-duplex 
mode, as other nodes call in, outgoing messages are sent to that node during the 
same call. 
Parameters 
Once you have created a link, you can modify any of the parameters by using the 
Modify Link Menu while the system is processing calls. The changes you make take 
effect when the next call is made. For step-by-step instructions on modifying a link, 
see CP 5714 in the procedural part of this chapter. 
lnquiring About a Link 
HOST 
1 
1 
1 
1 
2 
2 
HOST 
1 
1 
1 
1 
2 
2 
4-14 You can display network or port information for MESA-Net links by using the 
Inquire Links option in the Link Type Menu. The network report provides 
information about the network hardware, the timeout parameters (data receive, 
resend, and node inactivity), and the failure counts The report looks similar to the 
following one: 
NETWORK LINK DATA 
Mon Jul 10 10:42:04 1995 
NETWORK TIMERS 
FAILCNTS 
LINK MODE 
HARDWARE RCV, RSND, INACT RCV , SND 
1 ans 
60 60 60 7 7 
2 
orig 60 60 60 7 7 
6 
orig 60 60 60 7 7 
9 ans 60 60 60 - 7 7 
1 ans 60 60 60 7 7 
2 
orig 60 60 60 7 7 
No link data to report for Host 3 
No linkdata to report for Host 4 
-b 
.  ‘ 
The Network Link Serial Ports report provides information about the 
communications parameters for each link ( baud rate, parity, stop bits, data bits, and 
flow control) and tells you if the link is an answer or an originate link. This report 
looks similar to the following one: 
NETWORK LINK SERIAL PORTS 
Mon Jul 10 10:42:04 1995 
LINK 
PORT BAUD PARITY STOPBITS DATABITS FLOWCONTROL 
1 ans 9600 none 1 
8 ,enabled 
2 orig 9600 none 8 enabled 
3 ans 9600 none 1 8 enabled 
4 orig 9600 none 1 8 enabled 
1 ans 9600 none 
2 orig 9600 none 
No link data to report for Host 3 
No link data to report for Host 4 1 
1 
8 
8 enabled 
enabled  
						

							Configurating MESA-Net Async Hardware and Links 
For step-by-step instructions on inquiring about a link, see Cl? 5716 in the 
procedural part of this chapter. 
4-15  
						

							f  
						

							Device Number 
cl Name jI 
Answer Actions 
String Timeout Command String Timeout 
Originate Actions 
Command 
1 
2 
3 
4 
5 
4 
7 
8 
9 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 6 
7 
9 
10 
Disconnect Call Actions 
Command 
1 
2 Parameter Timeout 
i 5 
“u 
6. 
7 
Line Drop Signal (circle one) 
DTR RTS BREAK CTS DSR RING CD  
						

							Serial Port I 
Assignments j 
I 
/ Link Number 
c 
Device Number 
cl Serial Port Number 
cl 
1 Baud Rate: Parity: 
I 
64000 19200 2400 None Mark 
I 
57600 9600 1200 Even 
I Space 
I 
38400 4800 300 Odd 
i Data Bits: 7 8 Stop Bits: 0 
1 2 Flow Control: Enabled Disabled 
I 
1 Send Fail 
Count q Receive Fail Count 
I (l-255) (l-255) 
/ Data Receive Timeout 
0 seconds 
i 
i Resend Timeout 
c seconds ” 
I 
/ Node Inactivity Timeout 
c seconds