4.6. Compression layer commands

This chapter describes commands that configure the Compression Control Protocol (CCP) layer. All of these commands apply to the currently active bundle.

set ccp accept option ...

set ccp deny option ...

set ccp enable option ...

set ccp disable option ...

set ccp yes option ...

set ccp no option ...

These commands configure various CCP options. Each direction of traffic (transmit and receive) is independent from the other. All options default to disable and deny.

The enable and disable commands determine whether we desire the corresponding option on received data. The accept and deny commands determine whether we will allow the peer to request the corresponding option (which we must enable on our transmitted data).

The yes command is the same as enable and accept. The no command is the same as disable and deny.

The options available at the CCP layer are listed below. Note that the STAC and MPPC options require proprietary files that are not included with the normal mpd distribution.

stac

This option enables STAC compression.

mppc

This option is required in order to enable the Microsoft Point-to-point compression (MPPC) and/or Microsoft Point-to-point encryption (MPPE) protocols. However, this option does not actually enable MPPC or MPPE; you must use additional options (below) for that.

This option is required because of the way Microsoft implemented MPPC and MPPE as additional, optional sub-components of the MPPC protocol.

mpp-compress

Enables MPPC compression.

mpp-e40

Enables 40-bit MPPE encryption.

mpp-e56

Enables 56-bit MPPE encryption. Note: 56 bit MPPE encryption is only supported in FreeBSD 4.5 or later.

mpp-e128

Enables 128-bit MPPE encryption.

mpp-stateless

Enables stateless mode. This mode requires slightly more CPU time and is somewhat less secure, but allows faster recovery in the face of dropped packets.

radius

When enabled, MPPE types (40, 56 or 128 bit) and MPPE policies (whether encryption is required or optional) are controlled by the RADIUS server. In order to get MPPE to work you have also to enable mppc in mpd.conf.