pls help about mtu setting again
Hi Thank you for your reply about DSL mtu Now I have question about internet cable connection. ls it same as DSL? I tested it in my friend cable connection. 1470 is fine but 1480 is problem. Why it needs header in cable connection also? C:\Documents and Settings\dericping yahoo.com -f -l 1470 Pinging yahoo.com [98.137.149.56] with 1470 bytes of data: Reply from 98.137.149.56: bytes=1470 time=96ms TTL=50 Reply from 98.137.149.56: bytes=1470 time=91ms TTL=50 Reply from 98.137.149.56: bytes=1470 time=92ms TTL=50 Reply from 98.137.149.56: bytes=1470 time=89ms TTL=50 Ping statistics for 98.137.149.56: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 89ms, Maximum = 96ms, Average = 92ms C:\Documents and Settings\dericping yahoo.com -f -l 1480 Pinging yahoo.com [98.137.149.56] with 1480 bytes of data: Packet needs to be fragmented but DF set. Packet needs to be fragmented but DF set. Packet needs to be fragmented but DF set. Packet needs to be fragmented but DF set. Ping statistics for 98.137.149.56: Packets: Sent = 4, Received = 0, Lost = 4 (100% loss), Thank you for your help
RE: pls help about mtu setting again
1472 is the maximum ICMP payload size for standard Ethernet. 1480 fails because, well, it is 1472. -- () ascii ribbon campaign against html e-mail /\ www.asciiribbon.org -Original Message- From: Deric Kwok [mailto:deric.kwok2...@gmail.com] Sent: Wednesday, 23 June, 2010 12:53 To: nanog list Subject: pls help about mtu setting again Hi Thank you for your reply about DSL mtu Now I have question about internet cable connection. ls it same as DSL? I tested it in my friend cable connection. 1470 is fine but 1480 is problem. Why it needs header in cable connection also? C:\Documents and Settings\dericping yahoo.com -f -l 1470 Pinging yahoo.com [98.137.149.56] with 1470 bytes of data: Reply from 98.137.149.56: bytes=1470 time=96ms TTL=50 Reply from 98.137.149.56: bytes=1470 time=91ms TTL=50 Reply from 98.137.149.56: bytes=1470 time=92ms TTL=50 Reply from 98.137.149.56: bytes=1470 time=89ms TTL=50 Ping statistics for 98.137.149.56: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds: Minimum = 89ms, Maximum = 96ms, Average = 92ms C:\Documents and Settings\dericping yahoo.com -f -l 1480 Pinging yahoo.com [98.137.149.56] with 1480 bytes of data: Packet needs to be fragmented but DF set. Packet needs to be fragmented but DF set. Packet needs to be fragmented but DF set. Packet needs to be fragmented but DF set. Ping statistics for 98.137.149.56: Packets: Sent = 4, Received = 0, Lost = 4 (100% loss), Thank you for your help
pls help about mtu setting
Hi My DSL company asks me to set the modem 146 2 and my old company used 14 92 What is the different? Why it is not standard 1 500? Thank you
Re: pls help about mtu setting
google (or any search engine) is your friend. http://www.google.com/search?aq=fsourceid=chromeie=UTF-8q=mtu+1492+dsl http://www.google.com/search?aq=fsourceid=chromeie=UTF-8q=mtu+1492+dsl On 06/17/2010 08:19 AM, Deric Kwok wrote: Hi My DSL company asks me to set the modem 146 2 and my old company used 14 92 What is the different? Why it is not standard 1 500? Thank you
Re: pls help about mtu setting
On Thu, Jun 17, 2010 at 8:19 AM, Deric Kwok deric.kwok2...@gmail.com wrote: My DSL company asks me to set the modem 146 2 and my old company used 14 92 Why it is not standard 1 500? Because they're wrapping your packet inside another packet that they then transmit on a line with a 1500 byte MTU. The header on their packet needs a few bytes, so you can't have them. Regards, Bill Herrin -- William D. Herrin her...@dirtside.com b...@herrin.us 3005 Crane Dr. .. Web: http://bill.herrin.us/ Falls Church, VA 22042-3004
Re: pls help about mtu setting
Are you authenticating with PPPoE? If so, it has a maximum MTU size of 1492 due to the encapsulation overhead. --- Tom Pipes T6 Broadband/ Essex Telcom Inc tom.pi...@t6mail.com - Original Message - From: William Herrin b...@herrin.us To: Deric Kwok deric.kwok2...@gmail.com Cc: nanog list nanog@nanog.org Sent: Thursday, June 17, 2010 8:36:00 AM Subject: Re: pls help about mtu setting On Thu, Jun 17, 2010 at 8:19 AM, Deric Kwok deric.kwok2...@gmail.com wrote: My DSL company asks me to set the modem 146 2 and my old company used 14 92 Why it is not standard 1 500? Because they're wrapping your packet inside another packet that they then transmit on a line with a 1500 byte MTU. The header on their packet needs a few bytes, so you can't have them. Regards, Bill Herrin -- William D. Herrin her...@dirtside.com b...@herrin.us 3005 Crane Dr. .. Web: http://bill.herrin.us/ Falls Church, VA 22042-3004
