This page has been designed for printability. To print this document, click the Print button on your browser's toolbar. When you are finished, click the Close Window button located at the upper-right or bottom of the page to close this window and return to the previous page.
Poor network performance
DHCP - Dynamic Host Configuration Protocol
Poor performance on some internet applications such as:
Go to Network Connections -> WAN Ethernet (WAN PPPoE) -> Settings -> MTU
Change the MTU from Automatic or Automatic (DHCP) to Manual and adjust the value to 1500 for Cable and 1492 for DSL.
We have found that some ISPs are blocking the ICMP notifications that are required for PMTU to work correctly; by RFC1191 section 3.1 definition, PMTU can not send over a MTU of 576 unless the other side it is connected to authorized a larger MTU. Because the ICMP notifications are blocked no authorization takes place and PMTU falls back to 576 per the RFC definition.
A copy of the RFC can be located here: http://www.ietf.org/rfc/rfc1191.txt