Digi TransPort WR31 User Manual page 316

Configure network interfaces
Bring up interface and use idle period of s seconds
Causes the interface to become activated but rather than using the idle timer associated with
the interface, specify the idle timeout.
Inhibit other PPP interface if this PPP interface is disconnected but operational
When enabled, enables this PPP instance to inhibit other PPP instances if it is operational but
not currently active.
Attempt to negotiate DEFLATE compression on this interface
When enabled, causes the router to compress the data transferred over this link. When
unchecked, compression is disabled. The effectiveness of data compression varies with the type
of data but a typical ratio achieved for a mix of data such as web pages, spreadsheets,
databases, text files and (uncompressed) image files would be between 2:1 and 3:1. Using
compression has the effect of increasing the effective throughput. Using compression may offer
cost savings on a network where charges are based upon the amount of data transferred (such
as W-WAN networks). If the data is already compressed (such as .zip files or .jpg images) then
the compression algorithm detects this and sends the data without attempting further
compression.
Attempt to negotiate MPPE encryption on this interface
When enabled, causes the router to attempt to negotiate Microsoft Point-to-Point Encryption
(MPPE) with the remote peer. If the remote peer is unable to negotiate MPPE, negotiations will
fail. When negotiated, the PPP instance will encrypt the PPP frames as per the MPPE
specification.
MPPE key size
The values in this drop-down list select the length (in bits) of the encryption key. The options are:
Auto
•
40 bits
•
56 bits
•
128 bits
•
Auto indicates that the router will accept whatever the remote suggests. For the other values,
the remote must accept and request the key size specified, else the PPP negotiations will fail.
Digi TransPort WR Routers User Guide
Configure Advanced interfaces settings: External modems and PPP
316