NetComm NB1300PLUS4 - Manual (Page 47)

Rev. 1 - YML674 www.netcomm.com.au
NB1300Plus4 ADSL Modem Page 47
Advanced
MTU: Maximum Transmission Unit indicates the network stack of any packet is larger than
this value will be fragmented before the transmission. During the PPP negotiation, the peer
of the PPP connection will indicates its MRU and will be accepted. The actual MTU of the
PPP connection will be set to the smaller one of MTU and the peer's MRU. The default is
value 1492.
MSS: Maximum Segment Size is the largest size of data that TCP will send in a single IP
packet. When a connection is established between a LAN client and a host in the WAN side,
the LAN client and the WAN host will indicate their MSS during the TCP connection
handshake. The default value is 1432.
Automatic Reconnect: When it is checked, it will maintain the PPP connection all the time.
If the ISP shut down the PPP connection, it will automatically reconnect PPP session.
Authentication: When AUTO option is chosen, the PAP mode will run first then CHAP.
If you are having connection problems with PPPoA or PPPoE connections it is
recommended that you try forcing either PAP or CHAP modes.
Host name: Required by some ISPs. If the ISP does not provide the Host name, please
leave it blank.
Q1: If the PPP is disconnected after the Disconnect Timeout and how can I
reconnect it?
A: You have to go to the PPP Status under Admin Privileged column, choose the correct
PVC and Connect option, and then click Execute to restart a new PPP secession.
Alternatively you can click the CONNECT button at the bottom of the OnePage setup.
When should I change my MTU settings?
MTU settings should be changed to suit your ISPs recommendations if you are experiencing the
following symptoms;
■
General emails send but emails with attachments fail
■
Can achieve a connection but some web pages wont load or can't download files.
■ Windows Update starts but fails to complete.
■
Your ISP recommends you change the setting.
What should I change my MTU settings to?
MTU settings should be set to 1492 to start with, if you still have problems try lowering them
to 1456, 1400 or even as low as 750 to see if the problem improves. Your ISP is the best person
to contact to find out what MTU setting to use.
Note: MTU above 1492 is likely to cause problems and is not likely to improve data
throughput.