Delays in connection to HP3000 via VT-MGR vs TELNET

[Bengt Johansson]

Hi everybody !

This question is not pure PowerHouse but it shows up when using
PowerHouse.

We have an HP3000 at our office in Gothenburg and our customers are
spread out all over Sweden. Our customers mostly connects to the HP3000
using the Internet, but when there are problems with Internet or their
local network they all have a lifeline using the old technique with
direct telephone modem ( 19200 bps ), and that is always working.

When using Internet our customers use either the VT-MGR or the TELNET
protocoll in 'Connection Setup' in Reflection.
Some customers never have problems ( and that is good ).
But some customers almost always have problems ( and that is no good ),
and so have I myself sometimes when connecting from my home i Halmstad,
where I also have an office.

When using TELNET there are sometimes delays for every character sent. I
myself have seen delays up to 15 seconds but one customer have seen
delays up to 40 seconds.
This delay is from having pressed one button till the character pops up
at the screen.
Very annoying.
When using TELNET every character ( plus 40 extra characters ), when
pressing the button, are sent as a package from the user, to the HP3000
and then back to the user before the character pops up at the screen.
This TELNET delay became a bit shorter = better ( but not good enough )
after having changed 'Retransmission Interval Lower Bound' from default
4 seconds to 1 second in NETXPORT.GPROT.TCP in NMMGR.

Now to the question:
When using VT-MGR there is ALWAYS a delay in some PowerHouse Quick
screens, especially one heavily used screen with a primary file and a
detail file with many occurrancies and much data on the screen in Find
Mode after having read one set of data from having pressed Return to get
the next set of data till the new data pops up at the screen.
>From home with my relatively slow Internet connection this delay is
always 13 seconds with VT-MGR in this screen filled with data.
Using TELNET this delay is only between 1 and 2 seconds, but as I said
TELNET sometimes is too slow in another way.
Inside our office in Gothenburg with a fast LAN ( 100 Mbit/sec ) the
same screen gives a delay between 4 and 5 seconds with VT-MGR ( when the
TELNET delay is under 1 second ), and that is too much isn't it ? And
the 13 seconds mentioned above I can't stand. Would you ?
When using common MPE commands like LISTF or other, there are no delays
at all inside the fast LAN neither with VT-MGR nor TELNET, so why when
using PowerHouse ?

When using VT-MGR every pressed button is echoed to the screen locally
and there is a package sent to the HP3000 only when Return is pressed,
so this protocoll should be more efficient, but at least in PowerHouse
it seems not to be so efficiant.

Does anyone know a prescription to solve this problem ?
Some of my customers hate these delays so much that they use the
telephone modem instead of Internet, and have to pay the telephone cost
for that, when Internet is free when you have a fixed connection.
I have asked HP Support, but they have not given me any solution yet.

Another queer question is why some other customers NEVER have problems
using TELNET.

We use MPE 6.0 and  PowerHouse 8.29.D3.

Best regards
Bengt Johansson
AB Thoreb