Digi TransPort WR11 User Manual page 379

Configuring network interfaces
Inhibit this PPP interface if the following PPP instances n are Active | Active and not
out of service | Not out of service | Connected and not out of service
Inhibition of this PPP interface may be controlled by the state of other PPP instances. This
behavior is controlled by the options in this drop-down menu box.
If this PPP interface is inhibited and data needs to be sent
The options in this drop-down selection box control the behavior of the router in the situation
where the PPP instance is in its inhibited state but there is data waiting to be sent over the
interface. The options are:
Do not bring up interface
Leaves the situation as it is with the interface remaining inhibited.
Bring up interface and use normal idle period
Removes the inhibit state from the interface and uses the normal idle time associated with it
to control when it deactivates.
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
n
40 bits
n
56 bits
n
128 bits
n
Digi TransPort® Routers User Guide
Configure PPP and external modems
379