Telnet - Nagle and telnet lags.
Posted: Sun Nov 12, 2006 1:00 pm
I was screwing arround with my BBS today and I was in the majortcp admin menu:
Vircom inc. MajorTCP/IP
=======================
Administrative Menu
===================
S - Module Status/Statistics
A - Print ARP Cache
U - Online Users Info.
I - ICMP Stats.
X - Exit
Enter your choice (S, A, U, I or X) >
Here I use an undocumented item (R) to force MajorTCP to reload the control files it uses. (tcpsites.ban ect..) and I hit the (N) key by mistake.
(Early Morning lol)
I got this message!
Administrative Menu
===================
S - Module Status/Statistics
A - Print ARP Cache
U - Online Users Info.
I - ICMP Stats.
X - Exit
Enter your choice (S, A, U, I or X) > n
Nagle is now OFF
Enter your choice (S, A, U, I or X) >
Ok... what is nagle? I did a quick check on the net and found this...
Actually, it's who. John Nagle is the author of the algorithm that bears his name and its something that's been a part of TCP for years. It even has it's own RFC -- RFC896 called, significantly, Congestion Control in IP/TCP Networks. Check out the “backwards†spelling of TCP/IP -- that's how old this thing is.
John Nagle worked for Ford Aerospace and, to make a long story short, they had a lot of congestion on their network due to lots of tiny packets (think telnet). Nagle's brilliant solution was the Nagle algorithm which says, essentially, only send one small packet out without getting an acknowledgment (ACK). Otherwise, wait until you've got enough of them to send out a full-sized packet (or segment, if you want to get technical).
Ok.. so here is the question. Since I can turn this on or off, Should I and will it speed up telnet.
I'm going to do some testing with Z-Modem transfer through telnet as this is one thing that sucks through telnet.
Joe
Vircom inc. MajorTCP/IP
=======================
Administrative Menu
===================
S - Module Status/Statistics
A - Print ARP Cache
U - Online Users Info.
I - ICMP Stats.
X - Exit
Enter your choice (S, A, U, I or X) >
Here I use an undocumented item (R) to force MajorTCP to reload the control files it uses. (tcpsites.ban ect..) and I hit the (N) key by mistake.
(Early Morning lol)
I got this message!
Administrative Menu
===================
S - Module Status/Statistics
A - Print ARP Cache
U - Online Users Info.
I - ICMP Stats.
X - Exit
Enter your choice (S, A, U, I or X) > n
Nagle is now OFF
Enter your choice (S, A, U, I or X) >
Ok... what is nagle? I did a quick check on the net and found this...
Actually, it's who. John Nagle is the author of the algorithm that bears his name and its something that's been a part of TCP for years. It even has it's own RFC -- RFC896 called, significantly, Congestion Control in IP/TCP Networks. Check out the “backwards†spelling of TCP/IP -- that's how old this thing is.
John Nagle worked for Ford Aerospace and, to make a long story short, they had a lot of congestion on their network due to lots of tiny packets (think telnet). Nagle's brilliant solution was the Nagle algorithm which says, essentially, only send one small packet out without getting an acknowledgment (ACK). Otherwise, wait until you've got enough of them to send out a full-sized packet (or segment, if you want to get technical).
Ok.. so here is the question. Since I can turn this on or off, Should I and will it speed up telnet.
I'm going to do some testing with Z-Modem transfer through telnet as this is one thing that sucks through telnet.
Joe