VERY SLOW Dial In Connections with huge latensy and round trip time

[Snglks]

I have a problem with satelite communications (used 2400 connections with big latensy).
When a dial in user tray to connect timeout occured on LCP negotiation.

I find that I must use

ppp lcp predictive

statement but even with this nothing happen

 

[gwildfire]

what type of sat comms are you using? we have big problems with some systems over sat link and have to use an ITDM to channel our cct. Dont forger the min delay is roughly 600ms, so a round trip is 1200ms. There are also a lot of retrainsmissions, if you are using something like imarsat then you simply wont get an LCP connection to establish if your signal is low and you are not using 64K, are you trying to establish on a voivce channel? try a different encapsulation.

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http://www.Cisco-Engineer.com

for free Cisco rack access.

 

[Snglks]

We already use Inmarsat A and B communications with speed less than 9600. Problems exist with MNM that used even less connection speed.
What kind of encaptulation do you meen. Can you be more specific ?. We use Cisco Router for dial in and I don't know if I can change encaptulation type.

 

[gwildfire]

sorry didnt respond sooner, is 2400 the max speed ? what type of interface are you using on your router? we use the serial links going through an x.21 device (I cant name it as its military) If you are using a serial link then change the ecnap to hdlc rather than ppp. Also try reducing the mtu as if you are using the default 1500 then its probably too high. Or are you using a modem port without and intermediate device? try configring the bandwidth statements at both ends, and again reduce the mtu. if you are using a modem dialer type config try setting you diarler hold queue to a longer time period. If you have ppp quality set then turn it off.

 

[Snglks]

Thanks for responds
We Use Modems Connected on Asyncronus Interface (interface Group-Async1)
You can see router's configuration in Thread with title ( Bypass Callback )
2400 is the MAX speed of MNM Devices.
I will try to found more about your recomentations