[HECnet] LAT vs CTERM

[Kari Uusim ki]

LAT can perform quite well even over long distances. There used to be a nationwide customer network which was a LAT-only and it spanned tens of branch offices and hundreds of users spread all over the country. The longest distance between the VMS servers and the terminal server farthest away was approximately 1500km's (almost 1000 miles). Everything worked fine.

Concerning CTERM I think it would perform better by tuning the DECnet parameters to suit modern networks better. That would make other DECnet user protocols perform better as well.
Anyway, I assume CTERM isn't the best way to transfer files.


Kari


On 2.1.2013 18:36, Paul_Koning at Dell.com wrote:
That makes perfect sense: LAT is designed for a LAN while CTERM is a general purpose WAN protocol.   So the surprising part is that LAT works as well as it does over a WAN.   The reason probably is that modern WANs have performance (latency, in particular) good enough to match the "LAN" expectations of LAT.

	paul

On Jan 2, 2013, at 10:51 AM, <hvlems at zonnet.nl>
  wrote:

Look at it this way Sampsa: LAT degrades by a factor 3 while CTERM is better than half the performance.
LAT nor CTERM know they're travelling over an extended LAN.
So I'd think CTERM behaves better than LAT :-)
------Origineel bericht------
Van: sampsa at mac.com
Afzender: owner-hecnet at Update.UU.SE
Aan: hecnet at Update.UU.SE
Beantwoorden: hecnet at Update.UU.SE
Onderwerp: [HECnet] LAT vs CTERM
Verzonden: 2 januari 2013 12:20

So just for fun I did some speed experiments with CTERM and LAT using Kermit to send the same file.

WAN connection is KUHAVX (Finland) to RHESUS (UK).

CTERM
LAN:	30,000 CPS
WAN: 	16,400 CPS

LAT:
LAN:	100,000 CPS
WAN:	30,000 CPS


So LAT is as fast over a WAN link as CTERM is over a LAN..What's wrong with CTERM?

sampsa






.