Oracle Communications EAGLE (Software)
 

PLA-Support>Sun Systems>CommsGBU>Global Signaling Solutions>SN-SND: Tekelec Eagle 5
 

In this Document

Goal

Solution

Created from <SR 3-12773879871>

Applies to:

Goal

Questions :

1. For an association (SCTP), if re-transmit happens, how long or what is the condition so that this association goes down (its status becomes OOS) ?

2. If I am setting the parameter "RTIMES" for an HLR Association at10.
I'm sending the message ABC in this association. Can I understand that this HLR association will be OOS after I retransmit this ABC message 10 times ?
What happen if i'm sending two messages ABC and XYZ, and STP can send out ABC message after 5 times retransmit and STP send out XYZ message after 5 times retransmit ?

3. I found in MOS a document "Looking For Information On Congestion And Discard (Doc ID 1967186.1)" which concern congestion rule for LSL link. Can you share any same document for Sigtran link ?
 

Solution

Question 1. :

- The number of retransmissions is given by the parameter RTIMES. We can see in "rtrv-assoc:aname=xxxx" the parameter RTIMES.

- RTIMES parameter is the number of times a data retransmission will occur before closing the association.
  (3 to 12); the default is 10 : chg-assoc:aname=xxxx:rtimes=yy
=> For more details on this parameter in the Eagle documentation in the chapter named : Reference -> SIGTRAN User guide

Question 2 :

Indeed the RTIMES value for the number of retransmissions before closing the association concerns a same message.
When sending a particular message, Eagle will keep the message in its buffer until it receives the SACK.
If Eagle does not receive the SACK after the timer expiration, it sends again the same message, so this is the first retransmission.
If after RTIMES retransmissions (here it is 10), Eagle has not received any acknowledgement, then the association is closed.
Knowing that if Eagle does not receive the SACK for a particular message despite all the retransmissions of the same message, it will be the same issue for all other messages.

Question 3 :

Oracle Support team does not provide any document. You can ask the PM at Oracle and see if he has any .
However, we can add some information:

- When in congestion the Eagle will build packets to the max path MTU size to move as much data as quickly as possible. The Eagle will generate a packet up to 1500 bytes (bundling during congestion periods for maximum IP throughput).
- 0086 - IP Connection Congested. This message indicates that an IP association is congested. The card's memory has been exceeded, so the card cannot process all of the MSUs being received.
- for ITU : chg-stpopts:mtp31ctl=1
   MTP T31 congestion trigger level. This parameter specifies the signaling link congestion level at which the system starts the level 3 t31 timer. When the level 3 t31 timer expires, the associated signaling link is removed from service
   for realignment
- The command rept-stat-iptps:lsn=xxx is useful to check there is no IPTPS excess which could lead to congestion

Also, many informations about congestion in the following chapters of the Eagle documentation :
- Database Administration -> SS7 : search for "congestion"
- Maintenance -> Unsolicited Alarm and Information Messages : search for congestion and discard
- Reference -> Sigtran User guide : search for "congestion"

This solution has no attachment